DRYANDRA STUDY GROUP NEWSLETTER No

DRYANDRA STUDY GROUP NEWSLETTER No. 16 ~~~~:0728-151~ JULY 1989 SOCIETY FOR GROWING AUSTRALIAN PLANTS -I- DRYANDRA STUDY GROUP LEADER NEWSLETTER EDITOR Mrs. Margaret Pieroni Mr. Tony Cavanagh 16 Calpin Cres. 16 Woodlands Dr. ATTAD ALE OCEAN GROVE W.A. 6156 Vic. 3226 I hope all members in the Eastern states have survived the "big wet". I know parts of New South Wales and Queensland are almost awash and in Victoria, we are having our wettest winter for many years. It will be interesting to see how dryandras fare- please let me have your observations. In this issue, thanks to the sterling efforts of Margaret and Keith, I am able to bring a major discussion of the very complex Dryandra pteridifolia complex. This is preceeded by a description of the structure of the Dryandra flower together with line drawings by Margaret. Margaret also contributed an article on Dryandras in cultivation in Perth, and Hartley Tobin provided similar information for his gardens in Victoria. Ron Pearson supplied notes on his seed germination experiences and interesting comments on the weed potential of dryandras. Finally, there is a short note from me on the latest developments in Dryandra taxonomy- hopefully, something for everyone! Two projects which could help gain more information on dryandras are a survey of frost tolerance and a survey/recording of pollinators. My feeling, which is not backed up by more than a few casual observations and a couple of comments, is that dryandras are reasonably frost tolerant but we need confirmation. Any comments from members in frosty areas would be gratefully received. The actual pollinators of many dryandras remain a mystery and it would considerably help our knowledge in this area if, over this winter, all growers could observe their plants, or make observations in the field, and let me have the information. I am still puzzled by the lack of preference for dryandras, even D. formosa, among New Holland honeyeaters and other birds in my garden. The seed bank has been operating well, almost too well in fact, and Margaret is short of seed of some species. All donations of spare seed would be gratefully received- please ensure it is named correctly, or, if you are unsure, send a flowering specimen along with the seed. Two reminders. The Group has a slide-tape set of dryandras which is available for loan from Tony Cavanagh. It runs for about 40 minutes and there is no charge apart from the user paying the return postage. Normal loan period is one month. The set will be re-vamped when the genus is fully revised. Secondly, Margaret has ample copies of most back issues of the Newsletter, and the following are available from her- No's 1-10 (spiral bound), $6.50 plus No's 11 and 12 (spiral bound), $3.00 each plus postage; No's 13-16, Finally, a reminder that subscriptions for 1989-1990 are now due. I have held the cost the same as last year but the rising costs of copying and postage almost certainly mean a rise in subscriptions next year. Please send subscriptions to Margaret (cheques made payable to the Dryandra Study Group) and use the tear-off slip on the back page. This also has provision for comments, suggestions and questions. All the best with your Dryandra growing. And yes, I do have a new printer for my computer! The Dryandra flower; The flower heads of dryandras are made up of many flowers clust- ered together, Benthamwe description of the inflorescence is as follows; "flowers sessile, in pairs, in dense terminal or lateral heads in a involucre of numerous imbricate scale-like bracts and usually surrounded by a ring of floral leaves similar to the stem leavesn. Individual flowers are hermaphrodite and attached to a flat or nearly flat receptacle, The perianth (combined petals and sepals) forms a tube, topped when in bud by an oblong or linear limb (tip of $erianth tube). The limb divides into four claws during flowertng, splitting the perianth tube to nearly half way, with each claw holding an anther. The ovary at the base of each flower is very small and sessile. The long, thin straight style may not exceed the perianth in length. When, as in most cases, it is longer it will curve outwards through a split in the perianth until the stigma or tip of the style is freed when the limb breaks as.described as above. The style then straightens. This explains the form of most species in bud, eg D.toamona, where the perianth limbs are at first held together in a central cluster, while the thin, wiry styles curve out around the bud. As the stigmas are freed, this effect disappears. Key; a - receptacle, b - ovary, c - perianth, d - limb, e - anther, f - stigma. Glossary ; anther - that part of a stamen which contains pollen. exillary - in axil formed by leaf and branch. cuneate - broadest around middle and tapering to base. dentate - toothed. glzbrous - surface destitute of hairs. hcrmephrodite - with male and female parts. inflorescence - flower cluster. involucre - whorl of bract^ ~urroundingbase of flower. lanceolate - lance shaped; long and narrow. limb - swollen end of perianth. linsar - long and narrow with parallkl edges. peduncle - main axis of an inflorescence. perianth - collective term for calyx and corollz. pinnate - compound leaf with leaflets either side of a midrib. pinnatifid - leaf lobes cut half-way to midrib. pistil - female part of flower - ovary, style and stigma. plumose - hairs with feather-like branches. ovary - contains ovules - becomes fruit. r- receptacle - swollen head of flower stalk. reticulate - net-like veins of leaf. revolute - edges of leaf rolled inwards towards midrih, sinus - recess between lobes of leaf. stamen - male part of flower - filament and anther. stigma - female flower part which receives pollen. style - joins stigma to ovary. subulate - awl-shaped. terminal - at the apex. tomentose - covered with closely matted short hairs. villous - covered with long weak hairs. LATEST ON THE TAXONOMY FRONT It is pleasing to see two recent publications which have substantial information on dryandras. One is the weighty but very interesting Banksias, Waratahs and Grevilleas by John Wrigley and Murray Fagg, published by Collins. All of the currently named species are described together with leaf drawings which aid identification; in addition, 9 of Ted Griffin's proposed new species and three found by the authors during fieldwork are also briefly noted. The second is the long-awaited revised edition of How to Know Western Australian Wildflowers by William Blackall and Brian Grieve, revised by Grieve with assistance from Margaret Lewington. The major improvements on the earlier version are that leaf drawings are now scaled and each species description is accompanied by a small photographic reproduction of an herbarium specimen, not all of which show the inflorescences clearly. I will review both books in the December Newsletter but I would recommend them both to members for a detailed coverage of the genus as it is currently described. Alex George is still working on his revision for the Flora of Australia but we know there will be over 100 species and sub-species, some of them being old names which have been resurrected. Margaret and I have commenced work on a book on dryandras which will incorporate descriptions of all the newly named species as well as leaf drawings and drawings of seeds, seed capsules and, where possible, seedlings. Each will be illustrated by two or three photographs, one a close-up of the inflorescence and, where possible, another showing either habitat or, more usually, the whole or part of the plant. We are anxious that our information on cultivation requirements is accurate and I again would ask all members to supply brief notes on their plants, particularly those which have survived for several years and have flowered. We have only very sketchy information from Queensland, New South Wales and Tasmania and would welcome additional material from members in these areas. Examples of seedlings of various dryandras. Top row (1 to r) arctotidis preissii pteridifolia Bottom row (1 to r) species shuttie~or'thiana quercifolia * - 5- DRYANDRA PTERIDIFOLIA- AT LAST THE REAL THING 1 In April last year, I set out on one of my hyandza and Yerticordia searching trips hoping to find the real Lkxambra ~terldlfo* * U in flower. I had been given a few locations in the vicinity of the Fitzgerald River National Park and one further north to the east of Newdegate. Several years ago on a camping trip with the Wildflower Society we spent a night camped in a gravel pit on Old Ongerup Road where we found several plants of a "pteridifolia" form which I discovered later is D.* * itself. The plants, which are prostrate and spreading with upright tangled leaves were not looking very healthy at the time. They were suffering from drought and a sooty mould. On my return last year, I found them in a much worse state, the few remaining plants which had not died showed no signs of flowers or buds. The following month (May 1988), the district experienced disastrous (for the farmers) flooding rains which well and truly broke the drought of many years. Thinking that the good rains of last year would have revived the surviving dryandras and in the hope of my visit coinciding with the flowering period, I returned in April of this year on a similar trip. This time we approached. the gravel pit from the east and before reaching it we found some plants further south in Hamersley Drive in the National Park. I was delighted to find them in flower and photographed some of them.

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