Historical Flowering Records and Articles
(Please note it has not always been possible to retain the original formatting)
The Bamboo Society (EBS Great Britain) Newsletter No. 1 Spring/Summer 1989
FLOWERINGS
In a large and once glorious garden near Penryn, close to Falmouth in Cornwall, there is a large (4m. X 4m.) clump of
bamboo which is just starting its second season of flowering. The first year’s flowering only seems to have affected about 5% of the whole clump, and this year some 10% of the culms are affected. Never having seen the species before, I have very little clue as to what it may be, and perusal of available literature gave little indication of the plant’s identity. The one feature of the clump which really stands out, apart from its great beauty, is the striking colour of the emerging anthers which are nearly solid black.
David Crampton is zooming down to Cornwall at top speed to investigate, at the time of going to press, and anyone joining the June Bamboo Tour will have an opportunity to inspect the clump and opine. Samples have been sent to Kew for inspection, but at the time of collection (Easter) the flowers were only just beginning to emerge, and new material must be sent in June, when the flowers will be much better developed.
One of the few, or is it the only? Phyllostachys in flower so far this year is Ph. bambusoides ‘Geniculata’, which you will find referred to as ‘Slender Crookstem’ if you use McClure as your reference. There is a 50 litre container of this plant in Lincolnshire with 12 culms about ten feet tall, completely covered in flower. There is not a single leaf-bearing branch on the plant. Quite an impressive sight, though one worries for the future of the clump. Efforts are being made to ensure pollination, and as the plant is under a polytunnel there may be a good chance of some seed ripening. Fingers crossed.
There is a report in the American Bamboo Society newsletter, Vol X, No.2 (April 1989) from Michail O’Brien in Los Angeles, USA, of this form in full flower. He writes: “Presently, it is flowering like there is no tomorrow, with every branch carrying dozens of inflorescences. Defoliation was especially severe this winter (An extra cold one in the western US); it has lost almost all its
“normal” leaves, retaining only the stunted leaves that surround the emerging inflorescence. Currently, it is a plant of great beauty, with a very Japanese effect.
He also reports that Phyllostachys elegans is in flower, but after reading the saga of mistreatment and neglect that the plant suffered at his hands, it is maybe no surprise. that his elegans has decided on this kamikaze plea for attention.
Steve Renvoise of The Royal Botanic Gardens, Kew, reports that Thamnocalamus spathaceus (Sinarundinaria murielae) is increasing its flower production this year. Julian Campbell noticed one culm in flower in 1988, and now it seems to be spreading.
This species has not yet flowered in cultivation since its introduction to the U.K in 1913, except for a diminutive clone which flowered (in Denmark) earlier this decade. It will be interesting to follow this story as it unfolds, as what we all know and love as murielae must be one of the most widely cultivated bamboos in Europe, after Pseudosasa japonica. And we all know what has been happening to japonica for the last nine years or so.
Chimonobambusa marmorea continues to put out occasional flowering shoots, though most of the clumps which have flowered over the past four years or so seem to be settling down to their old hegemonist habits.
A clump of Semiarundinaria fastuosa at Penrose, in Cornwall, is in flower this year, with only two culms in a group of forty so being affected. This often seems to be the habit of fastuosa. The rest of the clump seems unaffected. There are several clumps of fastuosa in the grounds nearby, which one could surmise as having come form the same clonal source, that show no sign of flower at all.
Perhaps readers might like to comment on this species shy flowering habits, or indeed any other.
The Bamboo Society (E.B.S. Great Britain) Newsletter no.15 February 1992
BAMBOO FLOWERING RECORDS
1990
A. (Pleioblastus) chino Stream Cottage, Pulbrough, Sussex MB
A. (Pleioblastus) chino forma angustifolia Wadebridge, Cornwall MB
A. gigantea Pencarrow; Wadebridge, Cornwall MB
A. gigantea subsp. tecta Royal Botanic Gardens, Kew, Surrey MB
A. (Pleioblastus) graminea Bicton, Devon; Menabilly, Cornwall MB
A. (Pleioblastus) pygmaea var. disticha Pitt White, Uplyme, Devon MB
A. (Pleioblastus) simonii Wadebridge, Cornwall MB
A. (Pleioblastus) simonii forma variegata Wadebridge, Cornwall MB
Chimonobambusa marmorea Wadebridge, Cornwall; Pitt White, Uplyme, Devon MB
Pseudosasa japonica Royal Botanic Gardens, Kew, Surrey SR
Semiarundinaria fastuosa Nansidwell, Mawnan Smith, Cornwall MB
Sinarundinaria (Arundinaria) anceps Nansidwell, Mawnan Smith, Cornwall MB
S. (Drepanostachyum) falcata Bosloe, Mawnan Smith, Cornwall MB
Sasa kurilensis Royal Botanic Gardens, Kew, Surrey SR
Sasa palmata Hillier Arboretum, Hampshire MB
Sasa (Sasaella) ramosa Menabilly, Cornwall MB
Thamnocalamus spathaceus (Sinarundinaria murieliae) Royal Botanic Gardens, Kew, Surrey SR
T. spathiflorus Enys, Cornwall MB
1991
Arundinaria (Pleioblastus) chino forma angustifolia Wadebridge, Cornwall MB
A. (Pleioblastus) chino ‘Murakamianus’ Drysdale Nurseries, Hampshire MB
A. (Pleioblastus) fortunei Burncoose, Cornwall MB
A. gigantea Wadebridge, Cornwall MB
A. (Pleioblastus) pygmaea var disticha Pitt White, Uplyme, Devon MB
A. (Pleioblastus) simonii f. variegata Wadebridge, Cornwall MB
Chimonobambusa marmorea Pitt White, Uplyme, Devon MB
Phyllostachys nigra var. henonis Lanarth, Cornwall MB
Pseudosasa japonica Royal Botanic Gardens, Kew, Surrey SR
Sasa megaphylla ‘Nobilis’ Drysdale Nurseries, Hampshire MB
Semiarundinaria fastuosa Penjerrick; Nansidwell, Cornwall MB
Sinarundinaria (Arundinaria) anceps Nansidwell, Cornwall MB
Thamnocalamus spathaceus (Sinarundinaria murieliae) Wadebridge, Cornwall MB
Abbreviations: M B – Mike Bell; S R – Steve Renvoize.
The Bamboo Society (E.B.S. Great Britain) Newsletter no.16 October 1992
Extract from an article on Drepanostchyum falconeri by David McClintock
I have always looked upon this species as the only temperate example I had come across that approached the endlessly repeated dictum that all bamboos of the same species flowered at fixed intervals in the same year all over the world, and then died. A summary of its flowering years, so far as my notes go, is as follows :-
1821 Nepal
1847 Introduced to Kew as seed.
1873 – 7 Kew (from the 1847 seed),Ireland and elsewhere in Europe, Algiers and Sikkim.
1893 – 4 Kew (partial flowering)
1897 – 1900 India, including Darjeeling.
1902 – 8 England and Ireland. 1913-18 India (gregarious flowering).
1925 – 6 England (spasmodic flowering)
1929 – 32 England and Guernsey.
1935 New Zealand (North Island, Taranaki province).
1936 India
1964 – 8 England (one colony noted as 30 years old), Ireland, Scotland, Channel Islands, Nepal (flowering gregariously?)
I know of no plants that did not die after flowering, but seed was left (difficult to trace in my experience) and seedlings; I have three growing at Bracken Hill, which originally came from Scotland. These dates seem to indicate an interval of gregarious flowering in Britain of about 30 – 33 years. On that basis, I would have expected the next bout to come in the latter part of this decade.
However, Mike Bell had flower in Cornwall in 1990 and 91, with good seed and seedlings, however all the plants died in 1992, except one which came from a division made prior to flowering and which he tells me is in ‘full fig’ and showing no sign of flower. Perhaps this is a forerunner of flowering elsewhere, as there seems to have been in 1893 – 4 and 1925 – 6. I have heard of flower nowhere else.
The Bamboo Society (E.B.S. Great Britain) Newsletter no.17 March 1993
BAMBOO FLOWERING RECORDS: 1991 (additional to those listed in Newsletter 15)
Chimonobambusa marmorea Heligan, Cornwall MB; Stream Cottage, Pulbrough, Sussex PA; Royal Botanic Gardens, Kew DMcC; Platt, Kent DMcC; Newtownards, Co. Down, Ireland DMcC
Himalayacalamus (Drepanostachyum) falconeri Penjerrick, Cornwall MB; Fox Rosehill Gardens, Falmouth MB
Phyllostachys elegans Montet, Switzerland TG
Arundinaria (Pleioblastus) chino f. elegantissima Drysdale Nurseries, Hampshire MB
A. (Pleioblastus) linearis Bicton, Devon DMcC
A. (Pleioblastus) simonii Lund, Sweden (see Newsletter 15)
A. (Pleioblastus) variegatus Burncoose Nursery, Redruth MB; Stream Cottage, Pulborough, Sussex MB
Sasa megalophylla ‘Nobilis’ Drysdale Nursery, Hampshire DMcC; Stream Cottage, Pulborough, Sussex DMcC; Reigate, Surrey DMcC
Abbreviations: MB, Mike Bell; DMcC, David McClintock; PA, Peter Addington;
TG, Tony Grieb). Thanks to these members for the additional records listed above.
I have severely reduced the information which they originally submitted for the sake of economy. Mike and David ask that members tell them about bamboo species in flower which have not appeared so far on these lists. These members have sent in a lot of additional information concerning the flowering of the species listed. I hope to be able to present these fuller records at a later date. Ed.
The Bamboo Society (E.B.S. Great Britain) Newsletter no.18 July 1993
FLOWERING RECORDS
David McClintock and Mike Bell
The records published in abbreviated form in Newsletters 15 & 17 are presented here in full; additional information is contributed by Peter Addington, Brian Dixon and Tony Grieb. In Newsletter 17 (p.24) it was reported that Sinarundinaria nitida was in flower in Mike Bell’s garden. This was an error. The only known record to date for this country is Carwinion.
Arundinaria gigantea
In 1991 the clump at Wadebridge, Cornwall, and the parent clump at Pencarrow, Cornwall, were in flower and set seed. The clumps are reduced in size and vigour but remain healthy. The plant at Kew has been in flower since 1981. There is also a record from Montet, Switzerland.
Chimonobambusa marmorea
In 1991 the clump at Pitt White, Devon, continued to flower and may have died. The plant at Heligan, Cornwall, has isolated, vigourously flowering culms and sets fertile seed. At Stream Cottage, Sussex, the plant flowered and unexpectedly died. The plant at Platt, Kent, set seed and the Kew plant flowers year after year, sets seed and retains its vigour. Plants under glass at Newtownards, Co. Down, have also been in flower.
Himalayacalamus (Drepanostachyum) falcatum
In 1991 the plant at Bosloe, Cornwall, which was in flower from 1989, was without leaves and flowers; the culms remained green and may regenerate.
Himalayacalamus (Drepanostachyum) falconeri
In 1991 all clumps at Penjerrick were dead after their recent flowering. The division of these at Carwinion, Cornwall, showed no sign of flowering and the clump at Lanarth, Cornwall, had not flowered. At Fox Rosehill Gardens, Falmouth, the plant (probably a division from the Penjerrick plant) had flowered and died. These were badly damaged by cold before flowering while the Carwinion plant was not.
Phyllostachys bambusoides
In 1991 this was reported to have been in flower in Germany for the last 2-3 years, the plant at Stream Cottage remained in a vegetative state.
P. elegans
In flower at Montet in 1991.
P. nigra var. henonis
The plant at Lanarth had a few culms in flower in spring 1991.
A previous record of a plant in flower was at Baronscourt, Co Tyrone in 1974.
Pleioblastus chino forma angustifolius
An unvariegated clone at Wadebridge continues to partially flower and produce seed; another plant at Platt remains vegetative.
P. chino forma elegantissima
In 1991 this species had been in flower for the past four years with David Crampton, now at Fordingbridge, Hampshire. Seed produced mostly green progeny, only one seedling was variegated.
P. chino ‘Murakamianus’
In flower since 1990 at Fordingbridge, even the seeds are variegated. The plant at Stream Cottage remained green.
P. linearis
In 1991 David Crampton reported this species to be in flower all over the country. At Kew flowering started in 1982. The plant at Stream Cottage however shows no sign of flowering.
P. pygmaeus var. distichus
Plants at Pitt White were in flower in 1991 and setting seed.
P. simonii
At Lund, Sweden, there was massive flowering in 1991 with the production of viable seed and seedlings; see Newsletter 15.
P. simonii ‘Variegatus’
Both the parent plant and its variegated offspring at Platt continued to flower in 1991 and set seed with increasing abundance. Unvariegated offspring show no sign of flowering. It is rare that a seedling should breed true and start flowering almost at once; cf Bambusblatter 2(1984).
P. variegatus (P. fortunei, Arundinaria fortunei)
Potted plants at Burncoose Nursey, Cornwall, continued to flower and set seed in 1991 as did the plant at Stream Cottage. Also seen in flower at Scotsdales Garden Centre in 1993.
Pseudosasa japonica
In flower for many years, though plants were seldom seen dead Recorded in 1991 at Fordingbridge; Grayshott, Surrey; Kew;
Platt; Ightham, Kent; Blagdon, Northumberland; Castlewellan, Helen’s Bay, Mount Stewart and Rowallane, Co. Down;
Glenveigh, Co. Donegal.
Sasa megaphylla ‘Nobilis’
Plants in flower in 1991 at Fordingbridge and Stream Cottage with seeds and at Reigate, Surrey, with seedlings. Earlier flowerings were recorded in 1979 and 1981.
Semiarundinaria fastuosa
Partial flowering in 1991 at Penjerrick and Nansidwell, Cornwall; no seeds found. No records are known of seeds set on this species in the British Isles. In Castlewellan and Rowallane a few culms were also in flower in 1991.
Thamnocalamus spathaceus (Arundinaria murielae)
In 1991 a plant at Wadebridge flowered vigorously but partially, producing a vast quantity of seed in June. The seed germinated readily in two or three weeks. Flowering has also been extensive in several plants at Kew and at Hilliers Arboretum, Hampshire, in Denmark and San Francisco.
T. aristatus
Partial flowering was reported in 1991 from Enys, Cornwall, but has now ceased, with apparently no reduction in the vigour of the plants. No other record since a single clump flowered at Dereen, Co Kerry in 1978-1981.
Yushania (Arundinaria) anceps
One of several plants at Nansidwell had isolated flowers in the spring of 1991.
The Bamboo Society (E.B.S. Great Britain) Newsletter no.19 February 1994
TWO IMPORTANT FLOWERINGS
David McClintock
Ahead of any attempt to list what taxa have been producing flowers in the last year, two in 1993 deserve a special note. The first was Fargesia nitida, noticed on February 7th by Mike Bell at Carwinion in Cornwall, who sent me a specimen which is now preserved in my herbarium. This species was introduced by seed in the 1880’s and apparently no evidence is available as to what the seed let alone the inflorescence then looked like. But the latter proves to be very much like that of F. murielae, which further confirms its location in the same genus. The second is also due to Mike Bell’s eagle eyes.
On August 15th at Heligan he spotted just one culm of Chimonobambusa quadrangularis with good inflorescences, also now represented in my herbarium. There were two seeds, which unfortunately dropped into the litter.
I hope visitors will keep a look out for signs of germination. I know of absolutely no record anywhere of this species flowering, and such events have long been noted in the Far East. Do these two historical flowering events presage more? Will all members please look out for any flowering bamboos and let me have details for my records.
The Bamboo Society (E.B.S. Great Britain) Newsletter no.20 June 1994
THE SUDDEN MASS FLOWERING OF FARGESIA MURIELAE IN SCANDINAVIA
David McClintock
Suddenly there were headlines and large photos in the Swedish newspapers on 20 April announcing the “world sensation” of Fargesia murielae flowering all over southwest Sweden. On 22nd April I was sent a fine flowering specimen of this species by Soren Odum from his home near the Arboretum at Horsholm in Denmark. He wrote that it was flowering all over the country and also in southern Sweden, and that in Denmark too reports were appearing in the papers and on television. Soren noted that flowering started as soon as the temperature approached 10°c, and that temperatures of between 10 and 15°c caused a mass flowering.
Have members noticed that such such temperature rises so rapidly bring on mass flowering? I still find most plants over here sterile, but would like to be told of any that do come into flower and if there are fertile seeds.
The previous flowering of this species in Denmark was in 1973, 20 years ago no less! These plants were of a dwarf form, and the normal sized plants remained in a vegetative state. Are we now seeing the normal sized plants coming into flower for the first time? Ed.
A RECORD OF THAMNOCALAMUS (SINARUNDINARIA) NITIDUS IN FLOWER
Steve Renvoize
Recent correspondence with Simon Laegaard, a colleague in the herbarium of the University of Ärhus, Denmark, has revealed that Thamnocalamus nitidus is in flower there. This is the second report after that from Carwinion last year. He also reports the continued flowering of Thamnocalamus spathaceus.
FLOWERING RECORDS: 1993
David McClintock & Mike Bell
Arundinaria gigantea (A. tecta) Pencarrow, Cornwall. This clone is still in flower; the one at Wadebridge has stopped flowering.
Bambusa multiplex ‘Alphonse Karr’ Horley, Surrey. Growing out of doors.
Chimonobambusa marmorea Heligan, Cornwall. Pitt White, Dorset (producing seeds and possibly dying). At Kew not flowering, the first time for many years.
C. quadrangulariis Heligan, Cornwall. One culm in full flower, two seeds produced but lost.
Chusquea coronalis Leigh, Surrey. Grown in a greenhouse, prolific flowering but no seeds.
Fargesia (Sinarundinaria) nitida Carwinion, Cornwall. Seeds produced and germinated.
F. murielae Pennjerrick, Cornwall. Hilliers, Hants (since 1992). Fittleworth, Sussex. Wantage & Oxford, Oxon. Kew, Surrey. Chelsea, London. Pwllheli, Wales. Isle of Man. Mt Usher, Co. Wicklow, Ireland. Brussels & Kalmthout, Belgium (since 1992). Colmar, Alsace. Netherlands (source not recorded). Mainz, Muggensturm & Baden, Germany.
Himalayacalamus hookerianus Kew, Surrey. Edinburgh, Scotland. Same clone, grown in a green-house, in flower for several years, producing prolific fertile seed.
Indocalamus tessellatus Fordingbridge, Hants. Seeds produced.
Phyllostachys aureo-sulcata Wadebridge, Cornwall (a single odd flower from a potted division). Stockdorf, Bavaria (originally from USA, in flower for a decade, no seeds).
P. aureo-sulcata f. alata Kimmei Nursery, Netherlands.
P. aureo-sulcata ‘Spectabilis’ Edenbridge, Kent. Grown in a pot. No seeds.
P. bambusoides ‘White Crookstem’ Prafrance, Anduze, France. One clump died, another is still in flower.
P. elegans Wadebridge, Cornwall (seeds originally from USA). Stockdort, Bavaria (originally from USA and in flower ever since).
P. fimbriligulata Kimmei Nursey, Netherlands.
P. flexuosa Nansidwell (5 seeds) & Hayle, Cornwall. Cappoquin, Co. Waterford, Ireland (one or two culms, no seeds). California & Georgia, USA (in full flower). Australia (almost died out).
P. sulphurea var. viridis (“viridis mitis”) Prafrance, Anduze, France.
Pleioblastus auricomus Wadebridge, Cornwall. Borough Green, Kent. No seeds.
P. chino Wadebridge, Cornwall (seed set). Barnstaple, Devon. Pwllheli, Wales. New Ross, Co. Wexford, Ireland. No seeds.
P. chino var. hisauchii (P. hindsii auctt.) Kimmei Nursery, Netherlands. No seeds.
P. linearis Heligan, Cornwall (isolated flowers after seed set in previous years). New Ross, Co. Wexford, Ireland (no seeds).
P. pygmaeus var. distichus Heligan, Cornwall. Pitt White, Dorset.
P. simonii Lanivet & Wadebridge, Cornwall (still flowering, no seeds). New Ross, Co. Wexford, Ireland.
P. simonii ‘Variegatus’ (‘Heterophyllus’) Wisley, Surrey (no seed). Prafrance, Anduze, France.
Pseudosasa japonica Lanivet, Cornwall. Platt, Kent. Wisley, Surrey. Faringdon, Oxon. Batsford, Glos. Near Cardiff, Wales. Guernsey. Glasnevin, Dublin; Lisnavagh, Co. Carlow; New Ross, Co Wexford; Ireland. Prafrance, Anduze, France. Other localities also. All without seed. Plant at Cappoquin has never flowered.
Sasa “seikoana” (name not traced) Platt, Kent. Croydon, Surrey. Hoor, Netherlands (same plant). Stockdorf, Bavaria.
S. sp. Platt, Kent. Full brief flower (for a few weeks only) with seeds.
Sasaella sp. Platt, Kent.
S. ramosa Heligan, Cornwall. Kalmthout, Belgium. (1983-1987). Seeds.
Semiarundinaria fastuosa Heligan, Nansidwell & Penjerrick, Cornwall. Cappoquin, Co. Wexford, Ireland (grown in a pot).
Thamnocalamus spathiflorus Enys, Cornwall. Some culms in full flower, seeds germinated in two months.
Yushania anceps Nansidwell, Cornwall. In flower for some years, good seeds.
The Bamboo Society (EBS Great Britain) Newsletter no. 22 July 1995
FLOWERING RECORDS: 1994
David McCLintock & Mike Bell
This annual list is based largely on personal observation, supported by vouchers, and on information from the contributors listed at the end. In addition this time we have welcome information from Betty Shor in La Jolla, California. Her list, largely gleaned from the literature, went back several years and included many tender species, which are not included here. Names sent without vouchers have been assumed to be correct.
Arundinaria gigantea/A. tecta Pencarrow, Cornwall. Valkenswaard, Holland.
Arundinaria sp. ‘Tung Chuan 2’ Fittleworth, Sussex. Stockdorf, Germany.
Bambusa multiplex ‘Alphonse Karr’ Edinburgh, Scotland (in flower since 1992). Seattle, USA. New Zealand.
B. multiplex (cv. ‘Rivierorum’?) Handed to DM in a pot, from Carshalton, Surrey.
B. dissimulator Princess of Wales House, Royal Botanic Gardens, Kew.
Chimonobambusa marmorea Royal Botanic Gardens, Kew. Sparse flowers.
Chusquea culeou var. tenuis Leigh, Surrey. Wakehurst Place, Sussex. Fordingbridge, Hampshire. All from the same plant, ex Wakehurst, but no seeds produced.
Drepanostachyum falcatum La Jolla, California, USA (and earlier).
Fargesia murieliae Penjerrick & Wadebridge, Cornwall. Rose Ash, Devon. Pitt White, Dorset. Exbury, Hampshire (also in 1993). Leigh & Wisley (also in 1993), Surrey. Ivy Hatch & Platt, Kent. Lilleford Road & Royal Botanic Gardens, Kew, Surrey. West Bridgford, Nottinghamshire. Londonderry, Northern Ireland. Denmark. Southern Norway (full flowering since 1992 with seeds). Southern Sweden (widespread). Düsslingen (since 1991) and Munich, Germany. Seattle & San Francisco, USA. These are not all we have come across. Many with seeds, and doubtless many more. No definite deaths have been reported, but a few clumps have been dug up as shabby.
F. murieliae ‘Senlo’; ‘Leda’ Fordingbridge, Hampshire. Germany.
F. nitida Carwinion, Cornwall (one or two culms with seeds).
Himalayacalamus falconeri Nr Canterbury, New Zealand.
H. hookerianus Cappoquin, Co. Waterford, Ireland (with seedlings).
H. sp. (‘intermedia“?) A plant from Hilliers Arboretum, misnamed but correct identification uncertain. Leigh, Surrey.
Phyllostachys aurea ‘Albo-variegata’ Trebah, Cornwall. Fittleworth, Sussex. Valkenswaard(?), Holland. St Maur, France.
P. aureo-sulcata Amsterdam, Holland. Stockdorf & Munich, Germany.
P. aureo-sulcata f. alata Oregon, USA (on a stressed plant).
P. aureo-sulcata ‘Spectabilis’ Platt, Kent (also in 1993). Schellinkhout, Holland. Stockdorf & Hamburg, Germany.
P. bambusoides ‘White Crookstem’ Prafrance, Anduze, France. La Jolla, California, USA.
P. decora South Carolina, USA.
P. elegans Amsterdam, Holland. Marseilles, France. Stockdorf, Germany.
P. fimbriligula Valkenswaard, Holland. St. Maur & Prafrance, Anduze, France. Geneva, Switzerland. Carasco, Italy.
P. flexuosa Nansidwell, Hayle & St Ives, Cornwall. South of France. La Mortola, Italy. Los Angeles, USA.
P. nigra Savannah, Georgia. La Jolla, California, USA (with seeds).
P. prominens Carasco, Italy.
P. propinqua Carasco, Italy (gregariously).
P. vivax Oxford (a single large culm thick with flowers).
Pleioblastus auricomus Coldwaltham, Sussex (two seeds on one culm). Leigh-on-Sea, Essex (with seeds, we have no record of germination).
P. chino Wadebridge, Cornwall. Fittleworth, Sussex. Wisley, Surrey (angustifolia). Norfolk (originally from Drysdale Nursery). Geneva, Switzerland.
P. chino var. elegantissimus Pfaffenhausen, Germany.
P. chino var. hisauchii Valkenswaard, Holland.
P. chino ‘Murakamianus’ Fordingbridge, Hampshire.
P. chrysanthus Wadebridge, Cornwall. Stockdorf, Germany (since dead). Linz, Austria (originally from Copenhagen).
P. gramineus Wisley, Surrey. David Crampton writes that P. gramineus in the UK usually turns out to be P. linearis, but the name is probably correct in this case.
P. hindsii Leigh, Surrey.
P. simonii ‘Variegatus’ Falmouth & Wadebridge, Cornwall. Endsleigh, Devon. Fittleworth, Sussex. Wisley, Surrey. Geneva, Switzerland. Cambridge, Massachusetts, USA.
Pseudosasa japonica Penjerrick, Trebah, St. Blaizy & Heligan, Cornwall. Endsleigh, Devon. Exbury, Hampshire. Keston & Platt, Kent (and much earlier). Pampisford, Cambridgeshire (and earlier). Sark, Channel Islands.
Sasa nipponica Fordingbridge, Hampshire (in pots).
S. senanensis Marseilles, France.
S. veitchii f. minor Marktheidenfeld, Germany (this needs checking).
Sasaella ramosa Stockdorf, Germany.
S. sp. Platt, Kent (gregariously flowering, seeds infertile as in 1993).
Schizostachyum brachycladum Geneva, Switzerland.
Semiarundinaria fastuosa Penjerrick & Nansidwell, Cornwall.
Thamnocalamus spathiflorus Enys, Cornwall (as in 1993).
Yushania anceps Nansidwell, Cornwall.
Contributors: Peter Addington, David Crampton, Yves Crouzet, Wolfgang Eberts, Tony Pike, Max Riedlsheimer, Betty Shor, Chris Stapleton, Bill Sykes, Dominique Verdel, John Vlitos.
BAMBOO FLOWERING IN NORWAY
Geir Flatabe
Fargesia murieliae has started flowering in Norway – not every culm or clump, but quiet a few. F. murieliae is probably the most frequently planted bamboo in Norway since its first introduction to the Botanical Garden in Bergen in 1930, and some fifteen years later to the Agricultural University at As, south of Oslo: it is especially popular on the west coast. Most if not all the plants have been introduced from Denmark in one way or another. I do not know if there is more than one original clone in Europe, although I know some plants which are named ‘Simba’ and have not flowered. The first record of flowering came to the Botanical Institute of Bergen University from Alesund in 1993, and by 1994 there were records of flowering from all parts of Norway. The details of these records are as follows.
Akershus County, Eastern Norway around Oslo. Two records of flowering. No flowering at the Botanical Garden in Oslo or at the Agricultural University at As but in a private garden in As one clump was flowering. This flowering clump was situated in a very warm local climate and started flowering in early May. The owner of the garden was looking at a programme on Swedish television about bamboo flowering, and then looked out of his window to see that one of his own bamboos was flowering too.
Austagder County, the southernmost county. Flowering is recorded only at the Demmesmen Horticultural High School and at the town of Grimstad. At Demmesmen the sun-facing half of one large clump, 30 years old, was in full flower by May and seeding profusely by the middle of July. I myself collected at least 300g of seeds. Later in the summer at least three seedlings appeared near the parent plant. Seeds sown from the plant also germinated easily in a greenhouse. In the town of Grimstad I found two culms with in total 20 flower spikes, new vegetative culms were also being produced. At least 5 other clumps in the area were still without flowers.
Rogaland County, Figgjo. From a hedge of 15 plants one from the middle was divided in the summer of 1993 and the division planted at Eigersund. This division developed dense inflorescences, as did the mother plant left in the hedge; sparrows ate all the seeds.
Hordaland County, Radoy. One plant out of three with sparse inflorescences.
This plant had been trimmed to one metre and has never been allowed to achieve its full height. The one bamboo in Ulvik with only a few flower spikes was a division from this. In Ulvik, beside the Hardanger Fjord I have examined all the clumps I know, nine in all. Out of these, one clump showed intensive flowering in the middle of May, heavily seeding and apparently dying. In one more clump I found four flowering spikes, with seeds; it had started flowering late in May. Close examination showed that the same culm had flowered the previous year (1993). There are signs of fat buds which suggests that it will be flowering next year also. None of the other seven clumps at Ulvik has shown any sign of flowering.
Mere County, Spjelkavik, Älesund. In 1993 seeding spikes were discovered in a fifteen year old clump with culms four metres high, approximately ten percent of the clump was in flower, but there was good new growth. By 1995 new growth was limited to fewer than ten culms and there was nearly total flowering of the clump. Hens ate the seeds. One more clump flowered in 1995, out of a total of twenty clumps in Alesund. Seeds were sown at Milde Arboretum, with at least ninety percent germination and no seed dormancy. In Orsta three clumps are recorded flowering partially in 1993. In Svinviks Arboretum, Surnadal three clumps flowered in 1994. Flowering is also recorded at Eidsora.
Trendelag County. Although there are about twenty plants in this region in the middle of Norway there is no record of flowering.
Troms County. Nordkjosbotn. A clump of Fargesia planted seven years ago, one hundred metres from the sea at five metres altitude, has thrived in spite of the harsh, near arctic conditions of this location within the polar circle. In 1994 the whole plant came into flower and this year appears to be dying. Four years ago this plant was divided and the division planted a little further north at nearly seventy degrees latitude at Kvaleysletta, which should make this the most northerly living bamboo in the world;* it is not flowering.
There appears to be no obvious pattern to these flowering events. There might be a tendency for clumps which are injured or disturbed to flower first, or this may be due to favourable locations with hot, dry climates. Other factors such as microclimate change, soil, nutrients or size of clump do not seem to have any influence. I also have no explanation for the differences between partial and full flowering of the clumps. It is too soon to report on whether or not the plants die after flowering as the production of flowers has in most cases only just started. It does not seem that arctic winter darkness or arctic summer daylight influence flowering: Fargesia murieliae behaves in Norway just like it does everywhere else. It seems that flowering is just beginning; I would guess that ten percent of F. murieliae has been flowering in Norway in 1994 and perhaps only two plants in 1993. I still have seeds for anyone who would like to try to raise new clones of this wonderfully hardy bamboo. Ringve Botanical Garden at the University of Trondheim also has seeds from Svinviks Arboretum in its seed exchange list.
*At the time that I was preparing this newsletter I received the latest Southern California Bamboo, vol. 7, no 4, in which is published a note on Phyllostachys nuda growing a thousand miles north of Seattle; this puts it at approximately sixty degrees north. Ed.
FLOWERING OF FARGESIA NITIDA IN THE UK
Chris Stapleton
The first reported flowering of the Chinese bamboo cultivated in the west under the name Fargesia nitida was noted in this newsletter two years ago (Renvoize, 1993). This bamboo was grown in the UK from seed collected by Russian botanists in 1886, sent through St. Petersburg to James Veitch & Sons’ Royal Exotic Nursery in Chelsea in April 1889. The Director of the Imperial Botanic Garden of St Petersburg, Dr Batalin, stated in 1895 in a letter to Kew that it had been collected in north Sichuan by Potanin. E.Bretschneider, in a letter from St Petersburg to Kew in 1898, asserted that Potanin knew nothing about the seed, and that it had actually been collected by Berezowski in S Gansu in 1886. This is not as important as it might appear as both botanists were on the same team collecting in the border area where southern Gansu meets nortern Sichuan.
The first valid publication of the name Arundinaria nitida was in 1896 by Otto Stapf in the Kew Bulletin. Publication of the name in the Gardener’s Chronicle by Mitford in 1895 was not valid as there was no adequate description. Although Mitford later gave a full description in his book “The Bamboo Garden” in 1896, it was only published in April, after Stapf had already described it in the Kew Bulletin in January. Therefore Arundinaria nitida Stapf is the valid name.
When he described Arundinaria nitida Stapf was actually describing material from two different species. He had before him the living plants growing in the Bamboo Garden, a collection of a leaf-bearing branch from the plants grown in St. Petersburg, sent by Dr Batalin, labelled Potanin, north Sichuan in 1889, and also some of the actual seed from which it had been raised, labelled as collected by Berezowski in south Gansu in 1886. Unfortunately, he also had a collection of a completely different bamboo found by Henry in Hupeh Province, and he lumped the two bamboos together, citing both Potanin’s collection and that made by Henry.
McClure looked at both these collections in 1936 and annotated the “Potanin” collection sent by Batalin with his opinion that it ought to be chosen as the type of Arundinaria nitida. He separated the collection made by Henry as a separate species and later named it (McClure, 1940) as Indocalamus confusus. Henry’s collection defines that species, now known as Yushania confusa (McClure) Z.P. Wang & G.H. Ye. It seems that the designation of the “Potanin” collection sent by Batalin as the lectotype of Arundinaria nitida Stapf has never been formalised.
The application of the name nitida is extremely important as it typifies and therefore defines the genus Sinarundinaria. If the Potanin collection is used to typify nitida, then whatever genus our western Fountain Bamboo belongs to will be synonymous with Sinarundinaria. I have always assumed that it would tum out to be a species of Fargesia. As Fargesia was published before Sinarundinaria it would take precedence, and Sinarundinaria is “sunk” as a synonym of Fargesia. Of course, we cannot be sure which genus our Fountain Bamboo belongs to conclusively until it flowers. If on the other hand the Henry collection were designated lectotype then Yushania confusa would have to be called Yushania nitida, and as Sinarundinaria was published before Yushania we would have to change all our Yushania names to Sinarundinaria. Therefore it is very important to formalise the lectotypification of Arundinaria nitida Stapf as soon as we are sure that this bamboo really belongs in Fargesia.
Treatments of these bamboos by Chinese taxonomists have been inconsistent. Fargesia nitida has usually been recognised as a distinct species. However, it has sometimes been treated as a synonym of F. spathacea (Wang & Ye, 1981; Yi, 1983), although Yi later seemed to change his mind and recognised F. nitida as a distinct species (Yi, 1985). Without flowers of F. nitida as cultivated from Potanin or Berezowski’s seed this would obviously be a difficult synonomy to prove satisfactorily. Chao, Chu, & Hsiung (1981) looked at wild Chinese sterile material that they assumed to represent nitida, and as they found it to have “long” (no length specified) rhizome necks, they decided that it must actually be a species of Yushania. Therefore they decided to treat Yushania as a synonym of Sinarundinaria and still continue to use the name Sinarundinaria nitida (Chao, 1993). However, they have never seen its real flowers.
In 1993 two culms of a bamboo clump at Carwinion in Cornwall produced some interesting and distinctive flowers. Although they were very similar indeed to the tight unilateral spathed inflorescences of F. murieliae they showed substantial differences, suggesting that they represented the same genus, Fargesia, but a different species. Now stored in the herbarium at Kew they are intriguing, but not conclusively Fargesia nitida, as they have neither culm sheaths nor culms. As it is so important, Chinese taxonomists looking at the Carwinion collection at Kew are still dubious, thinking it may just be F. murieliae. It is hoped that some vegetative material from the same clump is being gathered to complete the collection.
Meanwhile Mike Bell passed me the information in May that Cliff Dadd of Ballaheannagh Gardens in the Isle of Man had a few clumps in flower and that he identified some of them as Fargesia nitida rather than F. murieliae. Relishing an opportunity for a busman’s holiday I dropped everything, including David Helliwell’s bamboo booklet, and went over to the island for a short break. It was practice week for the TT, and not quite the best time for me to have set out going the wrong way round the TT course on the road across the mountain, looking for Ballalheannagh. German motorbikes doing 150mph in the opposite direction on the wrong side of the road can be rather daunting. However, on the eastern flank of the mountain at the top of picturesque Glen Roy I found a charming garden, beautifully laid out with miles of stone steps beside cascading streams, and lavishly planted up over the last 15 or so years with a multitude of interesting young trees and flowering shrubs. Oriental influences are strong, and against the backdrop of a little Japanese bridge over a waterfall I found the first of several flowering bamboo clump, nearly leafless and clearly in full bloom for the second year.
The dark colour of the entire clump was striking, culms and flowers burnt a deep purple by exposure to the winter wind without the protection of foliage. At an elevation of 200m next to the sea and the fells, this is quite an exposed site, despite the palms on the sea-front in Laxey just a mile away. The densely bunched spathed inflorescences with spikelets arranged along one side of the rhachis showed it to be a Fargesia species. However familiar one is with a bamboo during its long vegetative period of growth, it is always difficult to recognise the same plant conclusively when it is in full bloom, and I had to look very carefully, trying hard to judge whether it was just more Fargesia murieliae or whether it could be Fargesia nitida. The culms were indeed very erect, not bending over much, but without the weight of foliage Fargesia murieliae would also not bend over. The leaves of F. nitida would of course not have the long drawn-out apices of F. murieliae but the only leaves were very new and small, and not really conclusive. The culms of F. murieliae are not usually as thin or as dark as this, but with the effect of the cold at this elevation on bare stems, who knows?
Pressing on up the steps to get a better feel for the site, three further species were quickly encountered, one Himalayan Thamnocalamus spathiflorus, one African Thamnocalamus tessellatus, and a Fargesia murieliae, conveniently also in flower to help me see what it and its flowers looked like in this exposed location. Seeing is believing, and with the two clumps so close all doubts went from my mind. The lower clump was clearly Fargesia nitida with thinner greyer culms and much darker flowers. Going back and forth other differences were soon highly apparent. The culm sheath scars on the upper clump (murieliae) were much larger, and the wax on the culms much thinner. The culm sheaths of the F. murieliae were tougher, shorter relative to the internode, wider at the top, more asymmetrical, and lacked the prominent reddish colouration along the ribs. The lower clump really was nitida.
Back at Kew the flowers quickly went under the microscope, and they have several characters in common with the 1993 flowers from Carwinion that also distinguish them from the flowers of F. murieliae. Clearly this is a separate species, the vegetative differences with which we are all familiar being supported by several floral characters as well. The lemmas are much smoother, with only a light covering of spine-like hairs towards the apex. The paleas are only shortly divided at the apex, while those of Fargesia murieliae are deeply cleft. The stamens have a nice distinctive characteristic, for eyes that have looked at lots of bamboo stamens anyway, having little nipple-like points, even at the base, while those of Fargesia murieliae are generally blunt at both ends.
Therefore we can now say conclusively that the Fountain Bamboo is a species of Fargesia Franchet. Although Yi Tong-pei made an attempt to publish the combination Fargesia nitida (Yi, 1985), because the original publication of Arundinaria nitida by Stapf was not cited, the combination was not valid. Fargesia nitida was in fact first validly published by Keng f. in 1987, in which he cited Stapf’s basionym.
It is very useful to have flowers of more than one species of Fargesia, as it helps us to judge the flowers of the mysterious little-known type species F. spathacea. It is now easier to assess its similarity to F. murieliae, with which it was considered synonymous for a while (Soderstrom, 1979). The differences between the flowers of Fargesia murieliae and those of F. spathacea were sufficient to convince me (Stapleton, 1995) that they were two different species, and to conjecture that the latter species was probably more like F. nitida in stature and vegetative characteristics. The flowers of spathacea differed from those of murieliae mainly in having fewer sheaths subtending the spikelets and ciliate spathes. So what of the flowers of these plants that I am now satisfied are indeed F. nitida? No prizes for guessing – they have very few sheaths subtending the spikelets and prominently ciliate spathes. Looking at the lemmas they are also less scabrous than those of F. murieliae and the stamens have small points at the apices, although they are not as markedly pointed at the base. Another characteristic of the spathacea collection was the solid branchlets. These are not quite solid in nitida, but they are nearly solid, and definitely thicker-walled than similarly-sized branchlets in murieliae.
The inflorescence of Fargesia dracocephala, kindly sent by Max Riedelsheimer, is also very useful. It is readily recognisable by the densely pubescent bracts, which like the glabrous bracts of Fargesia murieliae, are found at the base of nearly every spikelet, and by the tougher and extremely densely scabrous florets. We now have a good indication of the magnitude of variation to expect between the flowers of different Fargesia species.
The obvious conclusion from all this is that the bamboos named F. spathacea and F. nitida are not only very similar, they are close enough to be considered the same species. The very small differences in the flowers are well within the variation that could be accepted within a species, and the similarities in the fine detail of the inflorescence are substantial, relative to the differences between those of nitida, dracocephala and murieliae. The evidence is starting to stack up against nitida. So get ready for the next bamboo name-change. I’m really sorry about this but it looks as though it will have to be goodbye nitida and hello spathacea. This time, however, we hope to be giving the name to the right bamboo, the Fountain Bamboo rather than the Umbrella Bamboo, and we will be putting it into the right genus, Fargesia instead of Thamnocalamus.
There were two clumps of F. nitida in flower at Ballaheannagh, both in full bloom, with no new shoots, and looking very much as though they would never recover after flowering. There was also no seed, and a thorough search of the ground revealed only a single seedling. Interestingly it was growing right against a lump of cement, the least acid or possibly even alkaline spot in this clearly acidic site, where Cliff says the soil pH is about 6. Thus it looks as though after about 110 years the Fountain Bamboo is also about to flower gregariously and die. This is obviously not good news for those with a presently attractive clump, or those who had intended to sell stocks of the now doomed plants.
Steve promised me a half-day’s leave in lieu of the time spent looking at the flowering clumps in the Isle of Man, rising to a full day if I came back with flowers of nitida. I think it was worth a full day if I’ve proven the generic affinity of nitida, sunk Sinarundinaria conclusively, and solved the mystery of the real identity of spathacea. However, I don’t expect any thanks from all those who may have to start using the name spathacea instead of nitida.
Fargesia spathacea Franchet, Bull. Mens. Soc. Linn. Paris 2: 1067 (1893). Type: China, Sichuan Province, Tchen-Keou-Tin, Farges, 567 (holo. P; iso. K,E,US).
Syn.: Thamnocalamus spathaceus (Gamble) Soderstrom, Brittonia 31(4): 495 (1979) pro parte; Arundinaria spathacea (Gamble) McClintock, Garden (London) 105 (12): 502 (1980) pro parte.
Arundinaria nitida Stapf, Kew Bull. of Misc. Info. 1896: 20. Type: ‘Potanin N. Szechuan’, [cult. St. Petersburg, ii 1895, Batalin s.n.], excluding seed, ex China, N. Sichuan/S. Gansu, 1886, Potanin/Berezowski (lectotype K, selected here); Sinarundinaria nitida (Stapf) Nakai, Journ. Jap. Bot. 1935, xi,1; Fargesia nitida (Stapf) Keng f., J. Bamboo Res., 6(4): 14 (1987); Thamnocalamus nitidus (Stapf) Demoly, Bull. Ass. Parcs. Bot. France 13: 9-11 (1990).
References
Chao, C.S. (1993). A revision of the genus Arundinaria Michaux in China. J. Bamboo Res. 13(1): 1-23.
Chao, C.S., Chu, C.D., & Hsiung W.Y. (1981). A revision of some genera and species of Chinese bamboos. Bamboo Res. 1: 1-23.
McClure, F.A. (1940). New genera and species of Bambusaceae from Eastern Asia. Lingnan Univ. Sci. Bull. 9: 1-67.
Renvoize, S.A. (1993). In closing: Sinarundinaria nitida – in flower! Bamboo Soc. Newsl. 17: 24.
Soderstrom, T. R. (1979). Another name for the Umbrella Bamboo. Brittonia 31(4): 495.
Stapleton, C.M.A. (1995). Muriel Wilson’s bamboo. Bamboo Soc. Newsl. 21: 10-20.
Wang, Z.P. & Ye, G.H. (1981). Miscellaneous notes on Chinese Bambusoideae. J. of Nanjing Univ. 1981(1): 91-108.
Y1, T.P. (1983a). New species of Fargesia Franchet and Yushania Keng f. from Tibet. J. Bamboo Res. 2(2): 18-52.
Y1, T.P. (1985). Classification and distribution of the of the food bamboos of the giant panda. J. Bamboo Res. 4(2): 20-45.
The Bamboo Society (EBS Great Britain0 Newsletter no. 24 July 1996
FLOWERING RECORDS – 1995
DAVID McCLINTOCK & MIKE BELL
Arundinaria gigantea / A. tecta Maryland, USA.
Chimonobambusa marmorea Heligan, Cornwall.
Chusquea culeou var. tenuis Leigh, Surrey. Fittleworth, Sussex. Platt, Kent. Romsey, Hants. Most with fertile seed.
Fargesia murieliae Widespread. Fertile seed.
F. nitida Carwinion, Cornwall (still). Ballalheannagh, Isle of Man.
Gelidocalamus fangianus Hamburg, Germany.
Indocalamus latifolius Germany. Fertile seed
I. tessellatus Romsey, Hants.
Himalayacalamus falconeri Carwinion (single culm) & Wadebridge, Cornwall. Platt, Kent (17% of culms). Leigh, Surrey (ex Platt, Kent). Fertile seed.
Phyllostachys aurea Nijmegen, Netherlands.
P. aurea ‘Albovariegata’ Carwinion & Wadebridge, Cornwall. Fordingbridge, Hants. Fittleworth, Sussex. Platt, Kent. Prafrance (since 1994). Gründau, Switzerland. Germany. California, USA (since 1992, seedlings not variegated).
P. aureosulcata ‘Spectabilis’ Platt, Kent (since 1994).
P. fimbrigulata Fittleworth, Sussex. Switzerland
P. flexuosa Nansidwell, Trebah & Carwinion, Cornwall. Buckfastleigh, Devon. Fordingbridge & Romsey, Hants. Findon, Germany. Switzerland. Portland, Oregon, USA. Summertown, Tennessee, USA (variegated seedling).
P. propinqua Carasco, Italy.
P. viridiglaucescens Jena, Germany.
P. vivax Wadebridge & St Buryan, Cornwall. Fertile seed.
Pleioblastus auricomus Romsey, Hants. Platt, Kent. No seeds.
P. chino Fittleworth, Sussex. Wadebridge, Cornwall. Since 1994.
P. chino var. angustifolius Wisley, Surrey. Since 1994.
P. chino ‘Murakamianus’ Kenninghall, Norfolk. El Sobrante, Benicia, CA, USA. Seedlings all green.
P. chrysantha Wadebridge, Cornwall (again).
P. ‘Gauntlettii’ Kenninghall, Norfolk. Wadebridge, Cornwall.
P. linearis Heligan, Cornwall. Germany.
P. simonii ‘Variegatus’ Platt, Kent. Wadebridge, Cornwall. Germany.
P. variegatus Lostwithiel, Cornwall.
Pseudosasa japonica Platt, Kent (still). Handcross, Sussex. Jersey. Carwinion, Cornwall. Germany. California, USA.
Sasa veitchii ‘Minor’ Germany (since 1992). No seed.
Semiarundinaria fastuosa Hamburg, Germany.
Thamnocalamus spathiflorusm Enys, Cornwall (still).
David McClintock no longer feels able to continue recording the flowering of bamboos, and has asked Mike Bell to take over. Reports should therefore be sent to him from now on. They should be accompanied by:
- a sample of the flowers
- a mature culm node showing the branching pattern
- a branch with leaves
- a new culm sheath
These are very rarely all available at the same time, but please send as many as you can. Only samples requiring further verification will be preserved.
In future, we would also like to record the following relevant data:
- the extent of the flowering
- are there any leaves left when the plant is in flower?
- the age of the plant from purchase, division, planting, or the sowing of the seed
- the size of the plant
- the recent history of any stress factors (eg. drought)
- does the plant survive or die after flowering?
- is any seed is set?
- when does the seed ripen (i.e. fall off the plant)?
- are the seeds are fertile?
- are the parent plants or siblings also flowering?
- are any different species close by also flowering?
- abnormal occurrences, such as subsequent delayed regeneration or a change in the plant’s physical characteristics
- are there any natural seedlings?
Much of this information will not be available at the time of first flowering, but it is very important that it should be recorded in due course. The usefulness of the flowering records is directly related to the quality of the information received.
We propose to discuss the whole matter of keeping flowering records at the Society’s AGM at the end of the year.
The Bamboo Society (EBS Great Britain) Newsletter no. 26 May 1997
FLOWERING RECORDS – 1996
MIKE BELL
Bambusa glaucescens var. rivierorum Kew (outdoors). Temperature stress could be a factor.
Chimonobambusa marmorea Bracken Hill. Buckland Monochorum, Devon. Kew. This is the tail end of widespread recent flowering
Chusquea culeou Crudwell, ar Malmesbury, Wiltshire. Hillier Arboretum (single culm).
Chusquea culeou var. tenuis Stream Cottage. Bracken Hill. Hillier Arboretum. Reigate, Surrey. Most with fertile seed.
Drepanostachyum falconeri Carwinion. Bracken Hill. Hillier Arboretum. Reigate, Surrey. Widespread, with good seed.
Fargesia murieliae Widespread flowering continues, with large quantities of fertile seed.
F. nitida Further instances of flowering this year: Ness Gardens. Logan Botanic Garden. Roseland Peninsula, Cornwall.
Indocalamus latifolius Germany. Good seed.
I. tessellatus France.
Otatia aztecorum France.
Phyllostachys aurea Hadlow, Kent. Chelsea Physic Garden.
P. aurea ‘ Albovariegata’ Widespread flowering continues. Wadebridge, Cornwall. Kew. Guernsey. France. Switzerland. Good seed.
P. aureosulcata Wadebridge, Cornwall. Single flower.
P. fimbrigulata Kew. Switzerland. Probably the same plant.
P. flexuosa Widespread, good seed.
P. viridiglaucescens Mainz, Germany.
P. viridis Carasco, Italy.
P. vivax Wadebridge, Cornwall.
Pleioblastus chino Cumbria. France. Tail end of recent flowering.
P. humilis Kew.
P. ‘Gauntlettii’ Wadebridge, Cornwall.
P. linearis Stream Cottage. Falmouth, Cornwall. Germany.
P. pygmaeus Bracken Hill. Kew.
P. simoni ‘Variegatus’ Widespread but very partial flowering has continued for many years.
P. variegatus Lostwithiel, Cornwall.
Pseudosasa japonica Still flowering, but most clumps have now rejuvenated, particularly those in open aspects. Weak plants have succumbed.
Sasa nipponica Oxford. Stress could be a factor.
S. tsuboiana France.
S. veitchii ‘Nana’ Germany. No viable seed.
Semiarundinaria fastuosa Kew.
S. lubrica France.
MORE THOUGHTS ON FLOWERING
MIKE BELL
Bcamboos are one of the most enigmatic plant families that I know, and their captivating mystique is, to me, as much because of this as is their unique habits. Surely the strangest and most difficult to understand enigma is that of flowering. With flowering intervals often longer than a human generation, it seems that it will be a very long time indeed before we even begin to understand this process if we adopt the usual scientific procedure of collecting evidence in an unbiased atmosphere until the sheer weight of material forces a conclusion. So instead of recording flowering in studied surroundings, we have little alternative but to record all random observations and test them against preconceived theories. We have to answer the questions “why” before we investigate “how”, if we are to make any progress at all within my lifetime.
Most members of the grass family have evolved a complex, synchronized, flowering process, related to the precise hour of the day, time of the year, or weather condition. The systems are many and varied, but those of the majority are as little understood as the flowering of bamboos.* As the time scale for most is within our comprehension, it is logical that these systems have evolved because they are wind pollinated and need to act in unison to avoid self fertilisation. Not for them the luxury of some co-operative insect sorting out similar flowering species some distance away. Is it not logical that the reason for the bamboo flowering cycle is exactly the same, but related to the time scale of these very long lived plants? If they do not wish to self pollinate, which in normal circumstances is a very pointless exercise, then they have to flower in unison. It takes more than ten years for a bamboo to reach maturity, and therefore if they only flower once in their lifetime, with random flowering even closely packed plants would be lucky if a near neighbour was in flower at the same time. Not a conceivable way to perpetuate or evolve such a successful family. Also with flowering at such long intervals is it not more important than ever to ensure cross fertilisation?
But why do so many bamboos usually flower only once? Bamboos are very successful with just vegetative growth, particularly those with leptomorph (running) rhizomes, and is it therefore just coincidence that the running species are usually the ones that flower at the longest intervals? They are all very variable, both by mutation and by environmental forces, to enable them to adapt without starting another generation with all its inherent risks. Flowering is therefore probably reduced to a failsafe role, or to open up areas inaccessible to them by normal growth. Flowering only once at long intervals furthermore has distinct advantages, particularly if the parents die or lose all their above ground growth for a period. Any pests from mites to pandas are virtually eliminated, giving new growth an ideal start. Pests that feed on the seeds or seedlings cannot organise their breeding cycle to take advantage of a once only bonanza.
Viewed from this logic only life threatening forces would cause flowering ie. environmental threats and age. It is already well understood that environmental stress causes flowering. Typical of this is the example of five stands of Drepanostachyum falconeri at Penjerrick in Cornwall that flowered and died in 1991 after a very severe cold spell killed all their top growth and most of their roots.** Prior to this several divisions had been made, and one at Falmouth, which was also nearly killed by the cold, also flowered and died. A division at Carwinion and one in my garden were not damaged and did not flower. Both continued growing healthily until 1996 when they also flowered and died. This example suggests, in view of the time scale, that the severe weather did not instigate the flowering, but that it brought forward an inevitable conclusion, or by-passed the time clock. Other examples tend to reinforce this conclusion.
Bamboos are found in every continent except Europe and Antarctica therefore it would be surprising if there was a common cause for synchronised flowering, but the information that we have been collecting from plants growing in the west comes almost exclusively from the hardy species of South East Asia, a much smaller zone. I would suggest that all the evidence to date indicates a natural age related process as the most likely stimulant for the flowering of these species. In the wild, plants in one zone would all be born together and be subject to the same natural ageing forces and would age at a fairly uniform rate and reach “potential flowering” age at roughly the same time. By “potential flowering” I reason a hypothetical stage of growth, as with ivy for instance – juvenile, maturity, potential flowering, flowering, death (or rejuvenation). It is possible that the frequent reports of partial flowering without setting seed are often external indicators of this stage, as very often this terminates in gregarious flowering some years later. This is so well documented and understood that everyone is already lamenting the passing of Fargesia nitida, after one or two flowering plants have been found, possibly 10 years before it happens.
It is still difficult to comprehend how extensive and communal flowering occurs over exactly the same years in this very long ageing process. Survival pressures would eliminate stragglers, but even with this discipline it seems beyond reason. There must be other forces involved. Some years back I raised eight seedlings of Pleioblastus simonii and planted these close to the parent.*** When one was a few years old it started to flower although only about 1m high. The parent was still flowering and I concluded that the parent was somehow stimulating the seedling into abnormal behaviour. This brought to mind, at that time, that in the early days of the Pseudosasa japonica flowering cycle, I had raised some seedlings, and when they were big enough to put out I had planted them amongst the old flowering hedge, so as to take over. A few weeks later everything was flowering, and the only logical explanation then was that they had all died, although there were no dead plants to be seen. Looking back I realised that I had two examples of flowering seedlings. I confided in David McClintock, and he told me that he had had a similar experience with Yushania anceps some years before. These remained in my memory as some freak until a few weeks ago I received a letter, that is printed below, from Brian Dixon. Brian made a similar observation with Fargesia murieliae seedlings, where one of three was placed close to a flowering adult and immediately started flowering in unison (one was planted 2m away from the flowering adult, and two were planted 10 to 15m away). He also arrived quite independently at the same conclusion, that the old plant was sending out some signal to stimulate surrounding plants. I have no explanation why it stimulates seedlings, but it does, and that must indicate that there is a signalling mechanism there for other plants to receive also. It seems logical that this is a signal put out to communicate with others of the species that have reached the potential flowering stage, not to the seedlings.
It is well established that flowering in cultivation is much more sporadic and drawn out than flowering in the wild, but even if a species is all raised from one batch of seed, they are potted on, divided, moved, and generally stressed. They are subjected to a multitude of ageing forces that they would not experience in the wild, and each plant has its own different turbulent history before reaching the relative tranquillity of our gardens. But even then each garden has its own climate, and distinctive clones, that would not have survived in the wild, are treasured and nurtured even though they probably have a shorter natural life span.
I propose the following hypothesis therefore:
(a) That the bamboos that we grow go through a natural cycle of – juvenile – adult- potential flowering – flowering – death or resurrection.
(b) That the timing of this process is age-related.
(c) That when a plant reaches potential flowering it intermittently, or otherwise, flowers and that these flowers or the sterile florets give out a signal that stimulates surrounding plants of a similar age. (Also, for unknown reasons, seedling plants).
(d) Only when a response is received of sufficient magnitude from another clone does full flowering commence.
(e) If the plant is growing in isolation, with others of the same clone, or no response is received as would be the case with many cultivated plants, the plant goes through this stage without full flowering, and finally when age related death is imminent it flowers completely, so as to perpetuate the species by self fertilisation as a last resort.
(f) That the above stage is foreshortened if death is possible from any form of extreme stress.
These proposals are partly based on logic and partly on observation, so they need to be tested against your experiences. Brian’s letter was fundamental in confirming the earlier observations, and changing them from possible freak occurrences to positive happenings. In addition, considering how few people grow bamboos from seed, and even fewer who are going to put them near flowering adults of the same species, these were not infrequent examples. As requested last year we need more of your experiences recorded, to prove, disprove, or refine these thoughts.
On checking my records for the references for some of my statements I came upon an article in The Plantsman in 1971 by David McClintock relating to plant damage in the “incipient flowering” stage of bamboos (his term for my “potential flowering”). So this is another independent theory paralleling my thoughts.****
* Grounds, Roger: Omamental grasses. London: Christopher Helm, 1989, 42. ** Cf. Bamboo Society Newsletter 18 (July 1993), 15. *** Bamboo Society Newsletter 18 (July 1993), 16-17. **** Cf. Bamboo Society Newsletter 18 (July 1993), 14.
Letter from Brian Dixon
At the last AGM I bought seed of Drepanostachyum falconeri, of which some were sown in January ’97. Also available was seed of Fargesia murieliae, but as I had been given seed of this species by Mike Bell some 3 years ago I did not wish for more. The small quantity of D. falconeri seed sown germinated spasmodically with bottom heat and slowly grew away. The earliest seedling to grow seemed to produce a pheromone or an inhibitor to its closest neighbouring seedling which turned straw coloured and died off. At this stage I split the remaining seedling into their own pots, not wishing to lose more of my young 3″ specimens.
All of this might not have been so interesting had it not been for seeing one of those seedlings of F. murieliae sown 3 years ago producing its own seed on one of the resultant young plants only some 10″ tall and densely clumped making it 5″ wide.
The young plant in question has been located just some 6ft (2m) away from a large mature clump of F. murieliae for the past year now. This particular mature clone which I have been growing for the past 20 years now looks likely to flower/seed itself to death this year with virtually every culm producing an abundance of seed.
My question is now, is it known if our plants produce different pheromones (I use this word for want of a better description) given different circumstance in their life cycle. These questions add to a mystery which has yet to be fully clarified and may set a record for seed production from bamboo in such a short space of time.
The Bamboo Society (EBS Great Britain) Newsletter no. 29 August 1998
FLOWERING RECORDS – 1997
MIKE BELL
Arundinaria gigantea Pencarrow, Cornwall. Full flowering but still bearing some leaves and some culms still sterile. Seeds fertile. This plant has been flowering for several years and is declining in vigour.
Arundinaria (Gelidocalamus) fangiana PW Plants, Norfolk, and other locations.
Chimonobambusa marmorea Kew. Heligan, Cornwall. Platt, Kent; no seed produced, DM. All flowering to date has been partial with no reduction in plant vigour.
Chimonobambusa marmorea ‘Variegata’ Mark Fillan’s nursery, Devon; seeds produced all white or all green seedlings.
Chusquea culeou Drysdale Nursery, Hampshire; partial flowering but involving most culms; plenty of good seed which germinated well. Hilliers Arboretum, Hampshire; the single culm reported in 1996 is now in full flower with plenty of seeds; good germination but a lower percentage than above; no sign of any other culms preparing to flower. Wakehurst Place, Sussex, DM. Ness, DM. P W Plants, Nortolk, DM.
Chusquea culeou f. tenuis Hilliers Arboretum, Hampshire; flowering is extensive and the plant is in decline. Wadebridge, Cornwall; plant dead. Oxford, JV. Platt, Kent; plant dying DM. Wakehurst Place, Sussex; plant producing seed, DM. Most plants of both clones of this forma are now in flower and producing good seed which germinates well. The seeds are distinctive and the seedlings are totally different from the seedlings of the typical forma. After 3 months, the forma tenuis seeds were 50mm high and very similar to Fargesia seedlings, while the seedlings of the typical forma were 30 mm high with short wide leaf blades, half the length of forma tenuis, and the sheath tightly clasping the culm.
Drepanostachyum falcatum Trengwainton, Cornwall; flowering completed, good seed set; plant now dead.
D. khasianum Wadebridge, Cornwall; flowering started in 1998, now extensive.
Fargesia nitida Extensive reports of flowering but still only representing a small proportion of the total population. Most are partially flowering and not setting seed, a few are now in full flower and producing seed which germinates well.
F. murieliae Still flowering with good seed set on some plants.
Phyllostachys aurea Kew; Duchy Nursery, Cornwall.
P. aurea ‘Albo-variegata‘ Kew. Trevano, Trebah, Cornwall. Platt, Kent, DM. Most plants flowering and setting good seed. Seedlings not variegated. The Trebah plant was the first to be recorded in flower and is now recovering strongly from new rhizomes, but this new growth has untypically large leaf-blades, as on the seedlings, and has reverted to the typical form.
P. aureo-sulcata Wadebridge, Cornwall; partial flowering has taken place over the last few years; no seeds have been found.
P. flexuosa Carwinion, Cornwall and other places. Good seed set. The plant at Platt is now recovering, DM.
P. fulva Kew. Wadebridge, Cornwall (a division of the Pitt White plant), flowers immature, no seed set in 1997.
P. parvifolia Duchy Nursery, Cornwall; pot grown plant.
P. propinqua PW Plants, Norfolk, PW. Oadby, Leicestershire, RH.
P. propinqua f. bicolor PW Plants, Norfolk, PW.
P. vivax Wadebridge, Cornwall; a small recent planting which has now flowered and died without setting seed.
Pleioblastus chino Heligan, Cornwall; good seed set.
Pleioblastus chino f. murakamianus Drysdale, Hampshire, seed set, DC.
P. gauntlettii Wadebridge, Cornwall, seed set.
P. linearis Oadby, Leicestershire, RH. PW Plants, Norfolk. Burncoose, Cornwall.
P. simonii f. variegatus Wadebridge, Cornwall and elsewhere. Partial flowering with occasional seeds.
P. variegatus Burncoose, Cornwall; small plant in a pot.
P. auricomus Westcliff-on-Sea, Essex, BD; partial flowering with few seeds.
Pseudosasa japonica Heligan, Cornwall. Platt, Kent, DM. Other localities. The tail end of this long flowering period can still be seen in most regions. No seeds have been set.
Sasa nipponica f. variegata Norwich, Norfolk, RR.
S. sinensis PW Plants, Norfolk, PW.
Sasaella ramosa NP.
S. sp. Platt; flowering since 1984, no fertile seeds produced.
Semiarundinaria fastuosa Kew (near the Main Gate); completely flowering but no seeds set.
Yushania anceps Norwich, Norfolk, RR.
Thanks to all contributors. Flowering records have been authenticated by the author where no initials have been given, otherwise the events are recorded as follows: BD, Brian Dixon; DM, David McClintock; DC, David Crampton; JV, John Vlitos; NP, Neil Pearson; PW, Paul Whittaker; RH, Robin Hood; RR, Robert Ross.
In addition, we have eight reports from mainland Europe, but as this is obviously only a fraction of the true extent, it is considered unrepresentative and not of use in forming an accurate picture of events.
The Bamboo Society (EBS Great Britain) Newsletter no. 31 June 1999
FLOWERING RECORDS – 1998
MIKE BELL
These flowering records have been authenticated by the writer where no initials are given. Otherwise the events are recorded as follows: CS, Chris Stapleton; DM, David McClintock; DS, David Saunders; NP, Neil Pearson; RT, Ray Townsend;
RR, Robert Ross; TC, Tony Churly.
Arundinaria gigantea (could be ‘Tecta’) Pencarrow, Cornwall.
Arundinaria gigantea ‘Tecta’ Norfolk; RR.
Chusquea culeou Various locations including Cornwall and Stream Cottage; Bracken Hill, Kent; Sheffield; Chelmsford; Leigh, Surrey; DM. Almost all the early introductions have now flowered. Good seed has been set in most instances. Seed germinated well but raising can cause problems. The seedlings seem to require a well ventilated, cool, shaded location. It is early days yet, but the mature plants will probably die.
Chimonobambusa marmorea Again this plant is recorded as being in partial flower in various locations with good seed set. This species has been lightly flowering for many years and perhaps this is its normal behaviour. Heligan, Cornwall.
Chimonobambusa macrophylla ‘Intermedia’ This is a rare plant in this country but Robert Ross’s plant in Norwich is in flower. Ned Jaquith (USA) also reports flowering. Seeds are very large (up to 1cm long), green, and readily germinate.
Drepanostachyum khasianum All the plants recorded in 1997 have flowered, set seeds, and died. Seed was set in quantity and germination was good. Some growers found that storing the seeds a few weeks in the refrigerator aided germination. There is some doubt about the accuracy of the name of this species.
Fargesia nitida Flowering has again been recorded from many areas this year, mainly just a few culms on each clump. Good seed is usually set which germinates easily.Carwinion & Trebah, Cornwall. Kew; CS.
Fargesia murieliae Most clumps have flowered and died, but nursery plants can still be seen in flower. Bodmin area, Cornwall. David McClintock records new growths from the base of the old clump.
Himalayacalamus falconeri A few flowers only. Bracken Hill, Kent; DM.
Indocalamus latifolius Kew; CS.
Phyllostachys aurea The variegated clone is still in flower (see 1997 records). Good seed is set and Neal Pearson reports abnormal seedlings. Ned Jaquith (USA) also reports a number of seedlings with abnormal culms. Carwinion, Cornwall. Bracken Hill, Kent; DM.
Phyllostachys aureo-sulcata ‘Spectabilis’ One of two plants. DM.
Phyllostachys flexuosa Widespread flowering continues with good seed set, although seed is very small and often difficult to find. Carwinion, Cornwall. Kew; CS. Bracken Hill, Kent; DM.
Phyllostachys ‘Fulva’ The Pitt White clone of this plant is still in full flower in my Wadebridge garden, but it is almost certainly the same as P. flexuosa. It still has many leaves and seems to be little damaged by this heavy flowering. Wisley (clone not known); DM.
Phyllostachys nuda Fakenham, Norfolk. TC.
Pleioblastus chino Flowering in many locations and setting seed. Heligan, Cornwall.
Pleioblastus gramineus Bracken Hill, Kent; DM.
Pleioblastus linearis Kew; CS.
Pleioblastus humilis Kew; CS.
Pleioblastus simonii Heavy flowering involving about half the culms of several large clumps is recorded at Trelissick Gardens, Cornwall. Good seed is being set.
Pleioblastus simonii f. variegatus As usual, this plant is recorded almost everywhere as being in partial flower, and also as usual, this is associated with the variegated leaves. Wadebridge, Cornwall. Kew; RT & CS. Bracken Hill, Kent; DM.
Pseudosasa japonica A few plants can still be seen in the last stages of flowering. No seed is being set at this stage. Camelford, Cornwall.
Yushania anceps ‘Pitt White’ Llaniestyn, Gwynedd; two culms in flower; DS.
Most observers recorded a noticable reduction in the quantity of plants in flower this year. During 1998, two statements that are relevant to previous towering reports have come to my attention.
The first was spotted by Colin Thomas in The Bamboos by McClure, and concerns precocious flowering seen in some seedlings. On p277 McClure records (regarding the tropical bamboo Oxytenanthera abyssinica): “The seedlings were planted out in the field in the following rainy season and two of them bore seed for three successive years immediately following the planting. After the third year seeding ceased but the plants did not die. All the seed so produced was sown and about one percent proved to be viable. The resulting plants behaved in exactly the same way as their parents, that is they bore seed for the first three years of their life … Mr MacFadyen has carried out a progressive establishment of bamboos over several acres of land.”
The other article is taken from the American Bamboo Society Newsletter vol. 19 no.3 June 1998) pp 18-19. Punya Poudyal records instances of bamboo flowering in Nepal. He states that “Malinge Nigalo (Yushania maling) had flowered gregariously in Siding in 1965-66 and depleted completely for eight to nine years. Then it regenerated gradually”. This corresponds to our reports of Yushania anceps regenerating after several dormant years.
The Bamboo Society (EBS Great Britain) Newsletter no. 32 January 2000
GOLDEN BAMBOO FLOWERING
KARL BAREIS
Few people realise that the most widely distributed bamboo in the world is about to go through a change of life. The ubiquitous bamboo commonly called “Golden Bamboo” was carried by ancient traders to nearly every port where it would survive. From the Casbah of Marrekesh to Punta Arinas in Patagonia the Spanish transported the useful bamboo, and before them, probably Indian and Arab traders from the Gulf of Aziz to the ports of the Ming Dynasty. The occurrence of this one species can be used to chronicle the travels of these long-forgotten traders. Now that the flowering has begun we can use its unique fingerprint to separate the strains and speculate more closely on those specific strains and their patterns of global distribution.
The bamboo flora of the United States will undergo a big change as the estimated 30,000 acres of bamboo hedges planted with Golden Bamboo begin to disappear as result of defoliation due to a phenomenon known as “gregarious flowering”. The short bushy form of golden bamboo has allowed it to survive in places of extreme neglect, and many of these corner lots and fence line hedges have been around for so long that they go unnoticed. Like the century plants which send a tall bloom in the desert, expending all their energy to produce new progeny, bamboo mysteriously waits decades before producing millions of flowers from every branchlet and new sprout; three months later thousands of seeds shower down to attract birds and rodents which had never paid the Golden bamboo any special attention.
The common Phyllostachys aurea was first imported in the 1850’s to California’s Gold Country from its native Xiansi Province in west central China. Descendants of these original plants have now begun to flower throughout California. We can trace the history of cultural intermingling by focusing on the singularity of its appearance on the edge of long-forgotten Chinatowns where most other plants cannot survive the paltry soils left by avaricious miners in their haste to uncover the mineral wealth. It is ironic that the only gold left in the miners’ camps are the wispy clumps of Golden bamboo.
The flowering cycle appears to be sixty years. Nearly all the plants found are either divisions or seedlings of the original individual carried so long ago from China. In China, Golden Bamboo with its low branching and drought tolerance was grown on the edge of villages and used as a wind break hedge against dust blowing off the Gobi Desert. Its branches were used as brooms, and the bamboo canes, contorted and gnarled, were perfect as walking sticks for the elderly. In Xiansi province, when dried the shoots of P. aurea, became a food which could be stored indefinitely, reconstituted in a broth, and served in a myriad dishes. Once it arrived in the mining camps of California’s Gold Rush, the bamboo was transplanted into every community where the Chinese miners worked.
This flowering phenomenon has been expected for the past five years, because even though there are few old timers to remember having seen the last flowering cycle, the variegated form of Golden bamboo has been spotted flowering in Fuji Bamboo Gardens in Mishima town, Shizuoka Prefecture, Japan for the past five years. It is thought that the P. aurea would follow the example of P. bambusoides (“Timber Bamboo”), which began flowering first in the ‘Castillon’ form in 1975 in Japan, and the next year the common Timber Bamboo flowered along riversides throughout the country.
Timber Bamboo had been transplanted from Asia into gardens stretching from France to Chile. The flowering of P. bambusoides in Japan was soon followed by a wave of flowering that proceeded to cover the entire globe over the following five seasons. As it began to flower successively around the world, Timber Bamboo left a trail of dead and desiccated groves behind.
In that rare flowering, the Timber Bamboo nearly died out in the United States, taking several years to regain strength, coming back from a few residual surviving roots. Whenever bamboo flowers the next generation of growth is reduced or eliminated due to stress within the plant.
The current long cycle of flowering of Golden bamboo began once again in Asia, not far from the locality of the parent groves dating back several centuries. First observations came in April 1997 in Kyushu, southern Japan. In November 1997 it was flowering in Yunnan, southwest China. January 2000 finds it flowering along the freeway in Tarzana near Los Angeles, and in Santa Cruz, central California, and recent reports have individual plants flowering in Texas, Oregon and in Europe. If history repeats itself, during the next three or four growing seasons all the related plants will successively begin their sixty year pattern of gregarious flowering – a pattern that for some reason begins in Asia and eventually ends with the South American tropics. Historic records exist from past flowering cycles, and these records can be clues to what can be expected from the most widely distributed bamboo in the world.
FLOWERING RECORDS – 1999
MIKE BELL
Arundinaria gigantea (could be ‘Tecta”) The plants at Pencarrow, Cornwall, continue the cycle of flowering that has lasted a number of years. The plants have reduced in size and in number over the years and the flowering is quite heavy with viable seeds set.
Chusquea culeou Most plants of the early introductions are now in complete flower or have flowered and died. Seed is readily set and it germinates well. Seed was collected from the plants at Exbury and at Hilliers by the writer, and flowering was reported by Ray Townsend, David McClintock and Mark Pollard. Both the normal form and form ‘Tenuis’ at Exbury were almost dead from complete flowering during 1998, but showed some signs of new growth from the base. We have more information concerning precocious flowering from this plant, although this only causes more confusion. One of my seedlings, which accidentally germinated in the same pot as an indoor palm, flowered when 9 months old and is still in flower. It now has three small culms 7cm tall. The upper 3cm of each are primitive flowers, while the lower part has two or three healthy leaves. I have no other flowering culeou and the plant is growing in isolation indoors.
Chimonobambusa marmorea A few random flowers and dark seeds can be seen at Heligan, Cornwall.
Fargesia nitida This species continues to show a few random flowers on many plants but there are no reports of complete flowering this year and the number of flowers and flowering plants shows no significant increase. Reports were recorded from Ray Townsend, Chris Stapleton and David McClintock and very infrequent seed was collected by the writer from Exbury Gardens. This germinated well.
F. murieliae Flowering plants can still be seen. Ray Townsend reported plants in flower at Exbury and David McClintock at Limpsfield, Surrey.
Himalayacalamus falconeri A plant was found by Ray Townsend at Exbury gardens that had been in full flower during 1998. It was largely dead when found and although self-sown seedlings are common with this species there were none around this plant.
Indocalamus tesselatus A few plants at Jungle Giants are reported to be in flower by Michael Brisbane.
Phyllostachys aurea The variegated form is still in full flower everywhere. Flowers are reported at Kew by Chris Stapleton, Bracken Hill by David McClintock, and can be seen at Carwinion and Trebah, both in Cornwall. The last plant was the original plant to be found in flower and there are now good non-flowering new culms to be seen, but all are unvariegated. Some regrowth is variegated, but this is always associated with flowers.
P. flexuosa Widespread flowering and good seed is reported by Michael Brisbane at Jungle Giants, by David McClintock at Bracken Hill, and at Burton Agnes, Yorkshire and Exbury, Hampshire.
Pleioblastus auricomus (viridistriatus) This is a species which has only been known to have very random and occasional flowers and a number of widely spaced random flowers were seen by members of the party that toured Castle Howard this year. There were many plants growing well in light woodland but no seeds were found.
P. chino The species is widely flowering and can seen be at Exbury, Hampshire and Heligan, Cornwall, and is reported also by Michael Brisbane at Jungle Giants.
P. chino ‘Elegantissimus’ This form is reported as flowering at Treborth, Bangor by David Saunders.
P. humilis Flowering at Kew and reported by Chris Stapleton.
P. graminens David McClintock reports continued flowering at Bracken Hill, Kent.
P. linearis This species has been flowering slightly over many years and is reported as flowering during 1999 at Jungle Giants by Michael Brisbane.
P. simonii Heavy flowering and good seeds have again been observed this year at Trelissick, Cornwall.
P. simonii ‘Variegatus’ This form continues to flower and set seed. The variegated portions are almost invariably associated with a nearby flower. Reports from David Saunders at Llaniestyn, Gwynedd and Wadebridge, Cornwall.
P. variegatus (fortunei) David McClintock reports flowering at Wisley.
Pseudosasa japonica A few plants can still be seen in the last stages of flowering. A plant at Sutton Place is reported by David McClintock. Last year we reported that no seeds were being set which was based upon several years of observations by the writer. I was very surprised therefore to find several large seeds on a small plant at Pencarrow, Cornwall this year.
Sasaella sp. An unnamed species in the National Collection at Bracken Hill is reported as being in flower by David McClintock.
Yushania anceps David Saunders reports both the ‘Pitt White’ clone and the normal clone in flower at Laniestyn, Gwynedd.
Any uncredited listings have been authenticated by the writer.
The Bamboo Society (EBS Great Britain) Newsletter no. 34 December 2000
FLOWERING BAMBOO PRESENTS AN OPPORTUNITY
NED JAQUITH
Paper presented at EBS 2000, Falmouth, 18-20 August 2000
Abstract
When bamboo flowers it dies – anyone familiar with bamboo has probably heard this. Although this sometimes happens, it is not inevitable. This phenomenon can often be an opportunity in disguise. Many of the bamboos in cultivation were introduced as single propagules leaving us with but one clone of that species. There may be hidden in the genes of that plant useful characteristics that may be of use to the grower. New seed grown clones may be more vigorous, more hardy, more resistant to disease or insects, or perhaps more ornamental. Who knows what new traits may be found? Few have the knowledge or skill to create bamboo hybrids. But we can select among the natural seedlings for plants with desirable characteristics. It is a good idea to try to save the flowering plant as well as trying to grow new plants from seed. Clones with special characteristics are often not reproduced when grown from seed, so it is important to ty to conserve them vegetatively. Various methods have been suggested to revive flowering bamboo. More study needs to be done with this. Some have been effective in some cases, many have not. Often when a bamboo flowers the gardener will see it decline and rip it out without any effort at reviving it, or if it is not a visible eyesore, just abandon it to the forces of nature. Bamboos treated so often perish, although with proper care they might be saved.
When a bamboo flowers, as most of us know, it is in danger of dying. Flowering bamboos do not always die; although many do, especially in the case of gregarious flowering. Even an individual plant that suspends growth of new culms and foliage for the exclusive production of flowers may die. The phenomenon of gregarious flowering may involve many plants, but not necessarily all plants of that species or clone.* Sometimes bamboo of a species growing over a large area may flower at the same time. For those of us cultivating bamboo, we may have many plants that are a single clone or closely related seedlings and there is a danger that all or most of a given type may flower and die. As with all plants, flowering and reproduction from seed is necessary for the survival and spread of the species. There are bamboos that do not flower and, therefore do not set seed. But these bamboos are not found growing in the wild. They are cultivated plants, and are dependent upon man for their survival. Once mankind finds them of no further value, they will perish.**
Since bamboo is anemophilous (wind-pollinated, it must have many flowers at anthesis at the same time for successful spread of the pollen. The reason bamboos die after flowering is most likely so that the seedlings will receive the water, nutrients, room and sunshine that would otherwise be used by the mother. The seedlings are mulched by the debris of the dying parent. The mechanism for the timing of flowering and dying is a phenomenon not yet understood. It is one of nature’s baffling mysteries.
What should one do when a bamboo flowers? One option is to do nothing. The plant may recover, or it may die. You could even end up with a multitude of new seedlings at the base of the old plant. Even if it recovers, you will have a mess on your hands. When Otatea accuminata ‘Aztecorum’ flowered at the Huntington Garden near Los Angeles a few years ago, they left the whole dead plant in place. This was quite a bold choice for the gardeners of one of America’s premier gardens. It actually looked quite striking. It seemed to be a ghost of the living plant. Generally dead bamboos look quite dreadful. One could collect seeds and start a new generation, or could also just remove any dead and dying culms to keep the planting from looking so unattractive. It seems from our limited experience with Fargesias that some bamboos are destined to die when they flower, and growing from seed is the only way to save the bamboo. Another bamboo, Sasa megalophylla f. nobilis, a very attractive variegated bamboo, flowered in the early 80’s and perished. Rick Valley was able to get it to recover for a while by fertilisation and watering, but his finally perished also. The plant set seed, but even though we were able to germinate some, they all were rather chlorotic and soon perished.
My recommendation is to collect some seed and try growing a new generation under a more controlled environment, and also work towards reviving the plant vegetatively. If the plant is flowering on only a few branches or culms, no intervention may be required. This could be the precursor of a more thorough flowering though. If the entire plant is flowering, then measures are advised. Cutting out flowering culms, fertilising, and watering heavily has been suggested. But this may not help. We suggest that you try one of the following.
If the plant is large and in the ground, you should cut off any flowering culms and chop the rhizomes into sections with an axe where they are buried in the ground. This is followed by fertilisation, watering and continuing care. We learned this procedure from a Mrs. Lenora Michaels (who lived near Portland, Oregon). She told of doing this when her Phyllostachys bambusoides flowered, and it recovered. It would be interesting to learn how she knew to do this procedure. Many groves of P. vivax and P. bambusoides had been lost during the previous decade, and Phyllostachys bambusoides ‘Castillonis’ seems to have disappeared completely throughout the U.S. and Europe. If you have a smaller or potted plant, make divisions of the plant and cut off any flowering culms. Pot up the propagules in good potting soil. If any new culms start to flower remove them also. And of course, you must water and fertilise on a regular basis. Our guess is that this somehow interrupts the flow of some chemical signal allowing some propagules to quit flowering.
There has been some research done on the flowering and rejuvenation of bamboo in China. Hsiung et al. (1981) report on experiments with P. vivax, which flowered in Jiangsu and Zhejiang Provinces from 1969 to 1976. Their method for fast rejuvenation was to dig up rhizomes (without culms) from the flowering stands and cut them into 30-50 cm sections. These were dipped in a 100 ppm gibberellic acid solution for 5 hours and then buried in a cutting bed. When new shoots emerged, they were sprayed with the solution every two weeks. After 3 months, 36% of the culms from treated rhizomes flowered, while 64% of the culms from untreated controls flowered. After a year, the treated culms produced more normal, non-flowering culms than the controls. Hsiung warns that”… nitrogen fertiliser does not necessarily stop the flowering of bamboo stands, sometimes it tends to retard their rejuvenation.”***
We don’t know which plants we will be able to save. So far our method seems to work with at least some of the Phyllostachys. Some bamboos recover on their own after flowering while others may not recover vegetatively no mater what you do. The latter is more likely if the plant is small or weak at the onset of flowering, although even large and healthy, some bamboos such as Fargesia may flower and die no mater what you do. But like many generalisations, this does not always hold. Phyllostachys elegans at The Bamboo Garden has flowered sporadically every year for about 10 years while continuing to grow with moderate vigour. It has not been restored to a vegetative, non-flowering state, by our prune and divide strategy. It continues to flower and grow with no sign of stopping. Some species of bamboo seem to have a few plants in flower somewhere most of the time. In China there always seem to be some Moso plants flowering.
Growing from seed is exciting. It however, is not the way to save a flowering bamboo clone with variegated leaves or yellow or striped culms. These and other special clones are best saved vegetatively if possible. The seedlings will most likely return to the original type. You may, though, grow a plant that is more vigorous, hardier, more pest resistant than the parent. Or perhaps you will discover some other variation from the parent. Perhaps you could even create a bamboo hybrid if you have more than one kind in flower at once. We have grown several bamboo seedlings that have developed variegation at the Bamboo Garden. One of our most exciting is Fargesia dracocephala ‘White Dragon’ The variegation on this plant was not discovered until the plant was two years old, and the variegation seems to be getting more intense with age.
Some bamboo seed, such as Phyllostachys need to be fully ripened before harvest. This is especially true if the seeds are not to be planted immediately. Seeds of some bamboos are viable and may be planted while still green. Sasa, Indocalamus, and Pleioblastus are in this group. The seeds of Melocanna baccifera, a very large seed type germinate while still on the bamboo. When seeds are very easily removed from the inflorescence they are most likely ripe. Even with these bamboos, it is probably a good idea to let them dry and thoroughly ripen if they aren’t to be planted promptly. Leaving seed on the plant can be chancy though, as birds, bugs and rodents may harvest the seeds. If possible you may want to protect the plant. The seeds even may fall as the result of wind or just bumping the plant.
Seeds may be harvested individually by hand on a small plant. Or, sometimes seeds are found on the ground under the plant. If possible you can place a tarpaulin besides or under the plant and shake the flowering culms it. If you are sure the seeds are ripe, you can cut the culms to make it easier to shake them off. After collecting the seed and probably much chaff and debris, you can use the wind or a fan to blow away much of this waste.
I place the seed directly in small pots which I then water and place in plastic bags until they have germinated and the seedlings had grown a few inches. Care should be taken so as not to have the soil too wet. This has sometimes been a problem for us. If I have only a few seeds I sometimes put them between moist paper towels which are placed in plastic bags in a warm place until germination. This can take anywhere from just a few days to over a year. Each bamboo has a different schedule. Then, I put them in the small pots which I also put in plastic bags. A good soil-less mix, good watering techniques, and bright (not direct sun) light, are important to grow bamboo from seed.
Two of our recent projects are the recovery of Phyllostachys flexosa and the attempt of the recovery of Phyllostachys aurea ‘Albovariegata’. As you may surmise by the preceding statement, one project is working and the other is still in question. We have had success with the Phyllostachys flexuosa recovery. When the P. flexuosa flowered in the ground at our nursery, we dug several plants, cut off all the culms, and divided them into small propagules, and potted them in small pots. Much of the new growth flowered as had the original culms. So we removed any culms that flowered. But, by this time they had many healthy leaves and had given the rhizome a small increase in energy so that they were able to put up more small culms. Most of these new culms did not flower. Not all plants have recovered. Some plants were not carefully attended too, and died. Others, though, continue to flower. We also collected seeds and are growing a new generation of seedlings. There is new growth in the grove also, but this growth is where we cut the flowering culms so that we could easily harvest the seed. The new culms are very slender and some of them have started to flower. The plants in the grove might also recover, especially since we have cut out most of the flowering culms. And, of course they may have recovered on their own. Some other plantings of P. flexuosa in Europe and California have died. We have grown seedlings of flexuosa with some variegation in some plants resulting in two clones with some yellow culms, and one plant with all culms having a yellow sulcus. These are all too small to evaluate their value, but we will be watching them with anticipation.
The Phyllostachys aurea ‘Albovariegata’ is quite a different story. Vegetative recovery is what we wish to achieve when we are working with a special clone such as this. Our success has not been so clear, or perhaps we have hardly any success as of yet. Last autumn we dug some plants of Phyllostachys aurea ‘Albovariegata’ from a field near Eugene, Oregon. We first collected all the seed that we could, by cutting the culms and shaking them over a tarpaulin. We dug only a couple of plants and left several in the field intending to dig them later. The plants we brought back to the nursery, we divided sharply as we have suggested in the article we wrote with Dr. Richard Haubrich.**** These plants have not fared so well as those of the P. flexuosa. On a few small plants we have removed any culms that are not fully variegated. The culms on these are very small and spindly. Hopefully at least one will survive. Just cutting off the flowers did not seem to work. They continued to flower. Complete removal of flowering culms forces the plant to put up new culms. This worked, but any culms with variegated leaves flowered. New culms with no variegation did not flower. Some culms were partly variegated, and on these only the variegated parts flowered. It seems that we may loose the variegated Phyllostachys aurea. We have several plants that have recovered completely green with no variegation. One of them put up three beautifully variegated culms last year (1999). So, rather excitedly we removed all green culms and the variegated culms then flowered. We now have no variegated Phyllostachys aurea.
We also have grown seedlings of the Phyllostachys aurea ‘Albovariegata’, and a few of them showed a little variegation at first. But it has disappeared. We have marked these plants to watch closely to see if the variegation reappears. We have also noticed a very interesting growth pattern which we are also watching with interest. Some of the seedlings are very compact with the leaf sheathes overlapping one another quite closely while others growing in the same conditions are long and lanky. We wonder if perhaps those that are very compact may be the ones to even more strongly show the tortoise-shell, or Buddha-belly form that has inspired the Japanese name “Hotei-chiku” (“fairyland bamboo”). Or perhaps, the taller ones may grow to be like the variety ‘Takemurai’, without the congested internodes of the type species. Whatever the results it is exciting to speculate on the promise of the new seedlings.
Even with attempted vegetative recovery attempts, new varieties can occur. According to Dr. Richard Haubrich, the highly variegated Phyllostachys bambusoides we donated for the auction at the annual ABS meeting at Quail Gardens in October 1996 was found at the base of a flowered-out P. bambusoides ‘Castillonis’. I feel that for so highly variegated a plant to survive it must have been a sport rather than a seedling. The original P. bambusoides ‘Kawadana’ was found on a recovering, flowering, regular P. bambusoides***** Our current plant was found and saved as a sport from a flowering P. bambusoides ‘Castillonis’ by Mike Bell in Cornwall.******
So don’t just let your flowering bamboos perish, save them, and perhaps grow something new. Action to attempt vegetative recovery of a flowering bamboo should be initiated promptly since some bamboos die quickly after the onset of flowering. Some die in less than one year. The bamboos that flower and die so quickly may be beyond our ability to effect any procedure to revive them vegetatively. I fear that although we have had success with several Phyllostachys, many bamboos may be beyond our ability to save vegetatively.
*Lawson, A. H.: Bamboos: a gardener’s guide to their cultivation in temperate climates, 1968. 36-40. ** Muller, Lennox: Cultivated Gigantochloa: escape from death by flowering. American Bamboo Society Newsletter 17:1(1996), 4-7. *** Hsiung, W.Y. & others: An investigation on flowering and rejuvenation of Phyllostachys vivax stands. Bamboo Research 1(1981), 46-51. ****Jaquith, Ned & Haubrich, Richard: When bamboo flowers. American Bamboo Society Newsletter 17:2 (1996), 1-3. *****Okamuraa, Hata & Tanaka, Yukio: The horticultural bamboo species in Japan. 1986. 15. ******Bell, Mike, Cornwall. 1997. Personal communication.
(more to follow)