| BEN |
| BOTANICAL ELECTRONIC NEWS |
|---|
| ISSN 1188-603X |
| No. 416 October 20, 2009 | aceska@telus.net | Victoria, B.C. |
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I have always considered the consumption of edible wild mushrooms a safe and enjoyable, indeed healthful, pastime. I have my list of what I call 55 mile per hour mushrooms that I can identify glancing out the window at highway speeds. I pass up other edible mushrooms that require a good spore print or microscopic analysis to be sure of the identification. However, lately when I am leading a group in the woods, I have been reluctant to assure others that even my 55 mile per hour mushrooms are foolproof. What follows are some accounts of recent misidentifications that stagger the imagination. You see, I collect and report on mushroom poisoning cases from throughout North America as chair of the North American Mycological Association Toxicology Committee.
In early September 2009, I received an email report of severe gastronomic upset affecting four people (probably in Wisconsin) who had consumed what was reportedly Laetiporus sulphureus (Bull.) Murrill. I am used to getting reports of upset from the western look-alike, Laetiporus conifericola Burds. & Banik (Figure 1). However, even with Laetiporus conifericola, I would not expect every person in the group to have become ill. I would expect at most one or two sensitive individuals to have suffered gastro-intestinal distress, not the whole group. Besides, it is very rare for someone to react to Laetiporus sulphureus itself, just to its polypore look-alikes Laetiporus conifericola and Laetiporus gilbertsonii Burds. The answer came a few days later in another email reporting that Laetiporus sulphureus has a dangerous look-alike in eastern North America. The purported look-alike, and culprit in this story, was Omphalotus illudens (Schwein.) Bresinsky & Besl (Figure 2). The most stunning aspect of this story is that a few years ago I received another report of someone serving Omphalotus illudens thinking it was Laetiporus sulphureus. To me this is like not being able to distinguish green apples and limes. The only things that the two have in common are that they both grow on trees and both are green. The only things Laetiporus sulphureus and Omphalotus illudens have in common is that they are both somewhat orange and both grow on wood. Laetiporus sulphureus is a polypore and Omphalotus illudens is a gilled mushroom – how different can you get?
The same week I received a call from a poison center. They were fielding a call from a nurse at a hospital in another state who had identified a mushroom as Amanita muscaria (L.) Lam. (Figure 3). A young man had eaten 6-8 whole mushrooms in an apparent effort to get high and an hour had elapsed yet nothing was happening. The mushroom was described as having brown gills, among other features including bumps on the cap – and Amanita species have white gills unless old and rotting. Besides, consumption of 6-8 Amanita muscaria would constitute a massive overdose – 1 or 2 caps are what someone would eat attempting to get high. Six to 8 would be an attempt at suicide, though even that amount probably would not kill a healthy individual. So what was the culprit? I asked if the nurse could be requested to send me pictures and shortly some fairly blurry pictures arrived in my email – pictures of what was clearly an edible but bland and uninteresting species of Pholiota, possibly Pholiota terrestris Overh. (Figure 4). I was stunned but considering other mistakes I have seen, not altogether surprised. Amanita species have white gills that are not attached to the stipe and yield a white spore print. Pholiota species have brown gills that are attached to the stipe and yield a brown spore print. Amanita muscaria has warts on the cap that readily rub off or wash off in the rain. The scales on the cap of a Pholiota are part of the cap structure and do not rub off.
Amanita pantherina (DC.) Krombh. (Figure 5) has frequently been picked and eaten by persons who thought that they were eating Agaricus augustus Fr. (Figure 6). Do people also have trouble telling cantaloupe from oranges? Mushrooms are very safe to pick and eat if you eat distinctive species like Agaricus augustus so long as you read the description of the species and pay attention to what Agaricus augustus looks like.
A tragic case of mistaken identification was reported in Macleans.ca in an August 27, 2009 article: http://www2.macleans.ca/2009/08/27/judith-josephine-koritar-1944-2009/ According to the article the woman picked what she thought was Leucoagaricus naucinus (Fr.) Singer - syn.: Lepiota naucina (Fr.) P. Kumm. (Figure 7). She actually picked a truly close look-alike, “The Destroying Angel” or Amanita virosa (Fr.) Bertill. (in reality it was most probably Amanita bisporigera G.F. Atk., Figure 8). She checked her mushroom book and consumed the mushrooms which made her nauseous the next day and led to her death from Aspergillosis 19 days later. Her mistakes were subtle – she thought that the Amanita only grew in the woods and so a lawn mushroom would be safe – but not true if a tree is anywhere near. Virtually all Amanita species are mycorrhizal associates of trees, but a tree can grow near a lawn. Her second mistake was in not collecting the entire base of the mushroom. The volva, or “death cup” characteristic of the Destroying Angel group of mushrooms but not Lepiota species, is often just below the surface of the ground and is easily missed by a careless picker. Thus one of my rules – never eat an all-white gilled mushroom. By the way, the Destroying Angel mushrooms are exceptionally tasty – and thus poison several careless people each year. And there is a green to tan deadly Amanita, Amanita phalloides (Vaill. ex Fr.) Link (Figure 9) that came over on nursery stock from Europe over 100 years ago and is often found in urban areas.
I have another rule - never eat small gilled mushrooms. Several small Lepiota species contain the same toxins as the “Destroying Angel.” Lepiota subincarnata J.E. Lange, also known as Lepiota josserandii Bon & Boiffard (Figure 10) is one. Several Galerina species like Galerina marginata (Batsch) Kühner (alias Galerina autumnalis (Peck) A.H. Sm. & Singer, Figure 11) have the same deadly toxin, ?-amanitin. Numerous small Inocybe species contain a different toxin, muscarine. Inocybe species like Inocybe geophylla (Pers.) P. Kumm. (Figure 12) can kill a small dog but in a human cause severe vomiting and diarrhoea, profuse salivation and tear formation and constricted pupils.
There is no reliable rule that will tell you that a mushroom is edible. Poisonous mushrooms are no more likely to turn a silver spoon black than an edible species, nor will they change the color of rice they are cooked with. To be safe you must know how to identify each species that you choose to eat.
During the last decade many electronic databases of vegetation plots, mainly phytosociological relevés, were established in different European countries. These databases contain information which is extremely valuable for both testing various macroecological hypotheses and for nature conservation surveying or monitoring. The aim of this paper is to provide estimates of the number of vegetation plots there are in Europe, how many are stored in an electronic format and to assess their distribution across European countries and regions. We sent a questionnaire to the managers of national or regional databases of vegetation plots and other prominent vegetation ecologists. Meta-data obtained in this way indicate that there are > 4,300,000 vegetation-plot records in Europe, of which > 1,800,000 are already stored electronically. Of the electronic plots, 60% are stored in TURBOVEG databases. Most plot records probably exist in Germany, the Netherlands, France, Poland, Spain, Czech Republic, Italy, UK, Switzerland and Austria. The largest numbers of plots per unit area are in the Netherlands, Belgium, Denmark and countries of central Europe. The most computerized plots per country exist in the Netherlands (600,000), followed by France, the Czech Republic and the UK. Due to its strong phytosociological tradition, Europe has many more vegetation plots than any other part of the world. This wealth of unique ecological information is a challenge for future biodiversity studies. With the alarming loss in biodiversity and environmental problems like global warming and ongoing changes in land use, there is an urgent need for wide-scale scientific and applied vegetation research. Developments of information systems such as SynBioSys Europe and facilitation of data flow between the national and regional databases should make it easier to use these vegetation-plot data.
Check also:
The International Association of Vegetation Scientists organizes a conference and workshop on Vegetation databases and climate change 24 February - 26 February: 9th Meeting on Vegetation Databases Hamburg, Germany http://www.botanik.uni-greifswald.de/workshop2010.html?&L=1 Contact: Jürgen Dengler (dengler@botanik.uni-hamburg.de )
John James Audubon was one of the world's greatest painters of wildlife. He is best known for The Birds of America, a gigantic four-volume set of 435 paintings that to this day remains one of the largest books ever produced, the most expensive book ever sold at auction and an artistic achievement almost without parallel. Audubon also prepared a similar three-volume set of 150 outstanding paintings of North American mammals. In the last 2 centuries, dozens of books have been produced, either stressing Audubon's work as pure art or documenting the animals that were painted. The present volume is unique in emphasizing the plants that Audubon frequently illustrated along with his animals. Superb, full-color reproductions are shown of more than 100 of Audubon's best paintings, chosen for their excellent portrayal of plants. Each magnificent full-page plate is accompanied by information on the animals (mostly birds), the painting and (most particularly) the plants. An introductory, extensively illustrated chapter details Audubon's life and career — a fascinating story of heroic achievements in the face of great obstacles. A second chapter deals with Audubon's conservation legacy, a topic of considerable importance to the world's ongoing crises related to loss of biodiversity, degradation of the environment and global warming. This book will appeal to everyone who appreciates the stunning beauty of nature and the intriguing life stories of wild plants and animals.
The New York Botanical Garden Press is pleased to offer two new titles for Fall 2009:
Sphagnum, commonly known as peat moss, is widely used in agriculture, horticulture, and floriculture. Living plants are colourful and add much to the beauty of wetlands. It takes little training to recognize the genus, and most of the sections are almost as easy to recognize. Yet they are scarcely noticed by field botanists, and even bryologists tend to avoid them; they have a reputation of being taxonomically difficult but this applies only to a subset.
There are few taxonomic treatments of Sphagnum in North America, yet it is a fascinating genus whose species comprise an integral part of nearly all fresh-water wetlands. Almost all significant critical taxonomic characters are microscopic and require dissections and staining, which can, with a little practice, be easily self-taught. Even with a moderate amount of field experience, however, a novice can learn to recognize sections and some species in the field with certainty (although there are many species that even experts cannot distinguish without a compound microscope). All field identifications need to be confirmed microscopically. This volume will aid those who venture into identifying peat mosses.
This hepatic flora of central French Guiana is based on the study of about 1500 collections made by many different collectors. All species are keyed, described, and illustrated. Brief descriptions of the habitats of the species and of the lowland cloud forest of central French Guiana are also provided.
The flora consists of 175 species of liverworts in 59 genera and 17 families and 2 species of hornworts (2 genera, 2 families). The Lejeuneaceae are the most important family with 117 species in 37 genera. Eight new taxa are introduced.
This much-anticipated volume is the fourth and final part of the Guide to the Plants of Central French Guiana.
In addition, NYBG Press is offering a very special price on the entire four- volume Guide to the Plants of Central French Guiana. Purchase all four books for $128 -- a savings of $62 over the list price of $190. The set comprises 1,674 pages and 200 color plates. Part 1 treats pteridophytes, gymnosperms, and monocotyledons; Part 2 covers the dicotyledons; Part 3 deals with mosses; and the newly published Part 4 covers liverworts and hornworts.
To order, call 718-817-8721
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