Tuatara: Volume 7, Issue 1, September 1958
Toadstools (Agaricales) Including a Guide to the Main Genera
Toadstools (Agaricales) Including a Guide to the Main Genera
The last major group of plants left largely undescribed and undiscovered in New Zealand is the Agaricales or toadstools, of which we have a large representation of species, running to thousands. A great many of those that grow in the forest form a combination with tree roots called mycorrhiza (fungus-root). Most forest trees have mycorrhizas on which they are largely dependent for healthy growth. A proportion of our toadstools, particularly among the mycorrhizal members, is likely to prove endemic, though on the whole the degree of endemism among such lower plants (Cryptogams) is less than among seed plants (Phanerogams). A great deal of effort and a great many collections will be needed before a satisfactory record of the New Zealand Agaricales can be presented.
Any interested person can help by collecting, recording and preserving specimens, and may find in this activity an interesting hobby or spare-time research. Toadstools fade fast and are quickly attacked by multitudes of insects. For these and other intrinsic reasons special methods are needed in dealing with them. A complete record of a specimen requires a coloured drawing, a description according to such a scheme as that given in Table I, and a dried specimen, though a useful record is supplied by description and specimen alone. Material should be oven dried at 70-90°C. (e.g. in a domestic oven with the door open) and packeted, preferably in a sealed plastic bag. If the collector does not wish to build up a personal herbarium he could give his specimens to any other mycologist, including the writer, who would be grateful to receive extra material to incorporate in her own collection.
Recognition of different agaric genera is not easy because some of the characters used for classification show considerable variation, but with practice in handling specimens the worker in this field will soon be able to tell the common kinds. Different genera are distinguished by microscopic characters in addition to the macroscopic features which are used for the guide given in Table II. Before diagnosis is final the spores of the fungus must be examined with the microscope and tested for the presence of starch in the wall by staining with iodine solution, when those that are amyloid turn grey or blue; shape, size and sculpturing of the spores are also page 10 characteristic for each species. Additional microscopic features which are of importance are, firstly, the nature and arrangement of the hyphae building the fruiting bodies, and, secondly, the presence, position and nature of cystidia— large sterile cells sometimes with ornamentation— which may be found in the spore-bearing layer or hymenium, or fringing the gills. A book which is invaluable to the beginner and which fully explains all the
Description of Agarics
(Textbooks or a dictionary may be consulted for explanations of terms)
|PILEUS or CAP|
|Size: Measure in cms.|
|Shape: Flat, convex, hemispheric, campanulate, conical; depressed, umbilicate, infundibuliform; reniform, spathulate, fan-shaped.|
|Manner of growth: Rooted in soil, etc., singly, in groups; sessile, resupinate, imbricate.|
|Pellicle: Peeling or not, glabrous, silky or velvety, pubescent, fibrillose, tomentose, squamulose, papillate, tuberculate; even, zoned, striate, plicate, sulcate.|
|Moisture: Dry, hygrophanous, viscid, glutinous.|
|Margin: Entire, crenate, lobed; equals or exceeds gills.|
|Flesh: Homogeneous with or distinct from stalk; colour, thickness, texture; smell and taste (with caution).|
|STIPE or STALK|
|Colour: Outside and of flesh.|
|Position: Central, excentric, lateral.|
|Shape: Equal, tapering above or below, bulbous, solid, hollow, flattened, twisted, rooting.|
|Ring: Membranous, arachnoid, superior, median, inferior.|
|Volva: Colour; friable, evanscent, persisting.|
|Attachment: Decurrent, sinuate, adnate, adnexed, free.|
|Texture: Deliquescent, waxy, powdery, papery.|
|Shape: Thin, thick, deep, shallow, rounded at ends, forked, anastomosing.|
|Number: Distant, crowded, one series or long and short intercalated.|
|Margin: Straight, frilled, serrate, concolourous, white.|
|Colour, shape, surface, contents, size, staining with iodine (amyloid) or not.|
|Species of higher plants with which specimens were found.|
|DATE OF COLLECTION|
Collecting fungi is a seasonal pursuit full of interest. The mycelium, which is the mass of microscopic threads, or hyphae, that constitutes the fungus plant, permeates the soil, penetrates rotting wood, or clothes buried roots. One single plant, although unseen, may be fairly large, and this produces a crop of toadstools, which are its fruits, when conditions are right. Nutrients accumulate in the mycelial threads during the summer, then with the first burst of autumn rain comes a crop of toadstools. A dry summer and an early wet spell cause the most prolific fruiting. Most toadstools last but a few days though a few of the tough kinds persist for longer. Some appear with unfailing regularity each season whilst others are found only at long intervals, maybe only once in a lifetime of searching. Week after week the same garden or patch of bush will go on producing a succession of species, so that collecting fungi is quite different from collecting other plants. No list of species is likely to be even reasonably complete for any area till assiduous collection has continued for years, and there always remains the chance that a very well-known place will yield a rarity.
Though some toadstools are found outside of forests, it is in the bush that they reach by far their greatest development. In a good season toadstools are abundant in all kinds of forest, indigenous and exotic, but even in a poor season many may be found by careful hunting. Over the tree roots large toadstools spring from the mycorrhizas. Some tree species have their own species of toadstools, usually several kinds to one kind of tree, though all are not likely to be seen fruiting at once. The best known and most obvious toadstool is the red Amanita muscaria which belongs in all northern pine plantations in New Zealand, but which is not found in any amount further south than Nelson. In southern districts other fungi supply the needs of pine trees. A. muscaria also occurs with a few other exotic trees, such as Betula, and once the writer collected it in native scrub bordering Nothofagus forest, miles from any exotic trees, in the neighbourhood of Lake Rotoiti, Nelson. In the Nothofagus forests the most abundant mycorrhizal genus is Cortinarius, which produces large toadstools, often with strong purple colouring, under each species of beech. Many Russula species are always to be found in the same situation, also a large grey Amanita, species of Tricholoma, a few strikingly beautiful Lactarius and many smaller fungi. Climate appears to affect considerably the distribution and dominance of mycorrhizal toadstools, so that one species which is very important for a particular tree in one locality may be little use to the same tree growing under different conditions. Only four genera of gill fungi, Collybia, Armillaria, Pholiata and Pleurotus, appear to attack living trees at all commonly in New Zealand, though a great many different kinds are found on dead or fallen wood and in the litter.page break
|1. Agaricaceae— gill fungi||2. Boletaceae— tubes, etc., instead of gills|
|GUIDE TO MAIN GENERA OF AGARICACEAE|
|Characters of gills, stem and cap||SPORE COLOUR|
|Gills free||Ring and volva present||Amanita (fig. 7)|
|Volva (or cup) present||Amanitopsis||Volvaria (fig. 3)|
|Ring present||Lepiota (fig. 5)||Plutes||Psalliota Coprinus (fig. 8)|
|Gills adnexed) sometimes adnate)||Ring present Veil ring (like cobweb)||Armillaria (fig. 15) (gills even decurrent)||Pholiota (fig. 9) Cortinarius (fig. 12)||Psilcybe|
|(sometimes adnexed)||Cap with edge curved under||Collybia||(both with angular spores)|
|Whole plant very tough||Marasmius (fig. 1)||Panaeolus (tough)|
|Gills waxy||Hygrophors||Psathyrella (brittle)|
|Whole plant brittle||Russula (fig. 13)|
|Milking when broken||Lactarius|
|Whole plant slender||Mycena (fig. 6)|
|Gills sinuate||Tricholoma (fig. 14)||Hebeloma||Hypholoma|
|Gills decurrent||Clitocybe||Paxillus (gills forking)|
|(Laccaria, fig. 11)|
|Omphalia (fig 4)||Flammula|
|Gills as folds or ridges||Cantherellus (fig. 2)|
|Stem excentric or absent||Pleurotus (fig. 10)||Claudopus||Crepidotus|
Diagrams showing types of gill attachment, and sketches of examples of different genera: 1, Marasmius; 2, Cantherellus; 3, Volvaria; 4, Omphalia; 5, Lepiota; 6, Mycena; 7, Amanita; 8, Coprinus; 9, Pholiota; 10, Pleurotus; 11, Laccaria (Clitocybe); 12, Cortinarius; 13, Russula; 14, Tricholoma; 15, Armillaria.
In the early days of vigorous plant collection in New Zealand the fungi were included by only a few enthusiasts. First and foremost was the eminent botanist J. D. Hooker, who, as surgeon and naturalist on the Erebus, accompanied the British Antarctic Expendition 1839-1843. He collected extensively in all the sub-Antarctic lands which were visited, and when he reached New Zealand in 1841 he made a number of important journeys with Colenso during which fungi as well as other plants were gathered. After his return to England Hooker worked for years on the material from this expedition, publishing the results in a series of large volumes. The Flora Novae Zelandiae Part II, published by Hooker in 1855. contained descriptions written by the Rev. Berkeley, the leading English mycologist of the day, of twenty-seven gilled fungi collected either by Hooker or Colenso. In the following years Colenso continued sending hundreds of packets of fungi as well as many other plants to Kew. The only other botanical collector who also included fungi appears to have been the geologist Julius von Haast, who sent numbers of specimens as well as drawings made in the field from fresh material.
Hooker's correspondence with Haast, which is now preserved in the Alexander Turnbull Library, tells something of the difficulties which beset the famous botanist when he was struggling to finish his later work on New Zealand plants, the Handbook of the New Zealand Flora. It also gives us a picture of the background to these earliest published descriptions of New Zealand fungi. On May 3, 1865, he wrote, ‘The N.Z. cryptogams have driven me distracted and the work is really endless. I have slaved all winter through and am far from ready to print yet…. I am rejoiced to tell you that your fungi drawings are safe [after writing earlier, Jan. 18, 1864, that ’ the drawings never arrived here. I have searched and enquired…having thought that they had been sent to Berkeley.‘] I felt positive that I had sent them to Berkeley; but his repeated assurances that he had never seen anything of them made me over persuade myself that it had been a dream, or that I had confounded something else. Today he arrives from the country and brings them to me with many of them named, in the original cover addressed in my own writing to him, as soon as received from you ! Most of them are indeterminable without microscopic dissection of spores and specimens but 10 or fifteen are generically determined.’ When Hooker’s Handbook Part II was published in 1867 it included a section, written by Berkeley, which listed thirty-three species of gill fungi, but. as methods have changed so much through the intervening years, the material on which these earliest published records were based needs to be re-examined.
The indefatigable collector Colenso continued over the years to send hundreds of separate packets of fungi to Kew to be identified by Dr. Cooke and later by Massee, using their reports as the basis for lists of New Zealand fungi which appeared in the Transactions. All these early results are summed up in one paper by Massee (1898), in which he described 130 gilled fungi from New Zealand. Of these, twenty-three are endemic species described by Berkeley (18), Cooke (2) and Massee (3). Some of these are uncertain, page 15 e.g. of Hygrophorus cyaneus Berk. Massee comments, ‘ The present species is somewhat uncertain being described by Berkeley from a crude drawing only.’ Undoubtedly the description refers to a Rhodophyllus species which is a striking feature of the Nothofagus forests.
The part that toadstools play in the bush, in forming mycorrhizas, as parasites, or as agents reducing litter, makes their study important to forestry. However, in New Zealand only a few papers have appeared in this connection - Walker (1931), Birch (1937), Rawlings (1951), Gilmour (1954).
M. Roger Heim, the eminent French mycologist, came to New Zealand for the Seventh International Science Congress in 1949. During his visit he collected enthusiastically though the season for fungi was poor. On a few occasions the writer collected with him, and also gave him dried material from some earlier collections. On his return to France he published several important papers on the basis of his visit to New Zealand. His first note (1950) listed 121 species of Agaricales identified as to genus only, but including a new genus Cuphocybe fully described. This is close to Cortinarius but has sinuate to decurrent gills with ragged or scalloped edges. A later paper (1951) describes a new species of Boletus, B. paradisiacus Heim, from the head of Lake Wakatipu, and also a new Lactarius, L. nothofagi Heim, found under Nothofagus menziesii. Some further details of the species of Cuphocybe are included but full descriptions of the two New Zealand species which Heim discovered were presented, with coloured illustrations, in a later paper (1951). A further paper discusses the possible relationship between the purple Secotium and the genus Russula with reference to their occurrence in New Zealand beech woods. These results from the brief visit of an expert during an unfavourable season are stimulating and indicate clearly the possibilities which remain. The surface of the subject has been scratched sufficiently to show a rich interior which will accommodate many workers for a long time.
BIRCH, T. C. B., 1937— A Synopsis of Forest Fungi of Significance in New Zealand. N.Z.J.For. 4, 109-125.
GILMOUR, J. W., 1954— Armillaria mellea (Vahl) Sacc. in New Zealand Forests. Part 1. In Stands of Pinus radiata D. Don in Kaingaroa State Forest. For. Res. Notes N.Z. For. Service 1, No. 9, 3-33.
HEIM, ROGER, 1950— Sur la flore mycologique de la Nouvelle-Zelande. Comptes Rend. 230, 2245-2248.
—— 1951— Un mycologue dans la hetraie australe. Rev. Int. Bot. App. 31, 54-69.
—— 1951— Notes sur la flore mycologique des Terres du Pacifique Sud. II Cuphcybe nouveau genre neo-zelandais d'Agarics ochrospores. Rev. de Mycol. 16, 3-10.
—— 1951— Notes sur la flore mycologique des Terres du Pacifique Sud. III Sur les Secotium de Nouvelle-Zelande et la phylogenie de ce genre. Rev. de Mycol. 16, 129-153.page 16
HOOKER, J. D., 1855 - Flora Novae Zelandiae. London.
—— 1867— Handbook of the New Zealand Flora, Part II. London.
LANGE, J. E., 1935-1940 - Flora Agaricina Danica. Copenhagen.
MASSEE, G., 1898 - The Fungus Flora of New Zealand. Trans N.Z. Inst. 31, 282-349.
RAWLINGS, G. B. 1951—The Mycorrhizas of Trees in New Zealand Forests. For. Res. Notes For. Res. Inst. N.Z. 1, No. 3, 15-17.
WAKEFIELD, Elsie and Dennis, R. W. G., 1950—Common British Fungi. Gawthorn, London.
WALKER, Ethena, 1931— Observations on the Mycorrhiza of Pinus radiata. N.Z. For. J. 3, 43-44.
SINGER, R., 1949— The Agaricales in Modern Taxonomy. Lilloa 21, 1-830.