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BBBBB EEEEEE NN N ISSN 1188-603X BB B EE NNN N BBBBB EEEEE NN N N BOTANICAL BB B EE NN NN ELECTRONIC BBBBB EEEEEE NN N NEWS No. 67 January 4, 1994 Address: aceska@cue.bc.ca Victoria, B.C. ----------------------------------------------------------- Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2 ----------------------------------------------------------- COMING EVENTS IN VICTORIA, B.C. January 6, 1994 [Thursday] - Pacific Forestry Centre, Conference Room, 10:30 a.m. till noon: "Pacific Yew and Taxol: A Challenge for Sustainable Development" (A Seminar designed to convey the broad range of research projects being conducted on Pacific yew by scientists at the Pacific Forestry Centre) January 18, 1994 [Tuesday] - Swan Lake Nature House, 7:30 p.m.: "Botany Night - Succulents" - Identification of B.C. families: Crassulaceae and Saxifragaceae. January 19, 1994 [Wednesday] - Newcombe Auditorium, 8:30 till noon: "Natural History Colloquium." (A presentation on research projects conducted by the natural history curators of the Royal B.C. Museum) POSITION AVAILABLE - MYCOLOGY - OREGON STATE UNIVERSITY From: TAXACOM@HARVARDA.HARVARD.EDU Assistant Professor, Mycology. -- A tenure-track, 9-month faculty position is available in mycology. Teaching respon- sibilities include introductory and advanced courses in mycol- ogy, and contributions to the general biology curriculum. The successful candidate is expected to develop an extramurally- funded research program. Areas of research include, but are not limited to, evolutionary biology, population genetics and sys- tematics of fungi. The individual chosen will be responsible for the oversight of the mycological collection which is housed in the Oregon State University Herbarium within the Department of Botany and Plant Pathology. Application closing date: February 28, 1994 Position available: September 16, 1994 For more information contact: Chairperson, Mycology Search Committee Department of Botany and Plant Pathology Oregon State University Cordley Hall 2082 Corvallis, OR 97331-2902 Telephone: 503-737-5286 FAX: 503-737-3573 FOREST SUCCESSION AFTER 1480 ERUPTION OF MT. ST. HELENS Ring counts on Douglas-fir (Pseudotsuga menziesii) stumps were used to reconstruct the early development of old-growth forests northeast of Mount St Helens, Washington, after catastrophic forest disturbance by tephra fall from an eruption in 1480. In addition to documenting volcanic and other disturbances in forests near the volcano, this investigation tests the hypotheses that distant seed sources, repeated disturbances, or competition from shrubs and hardwoods caused Douglas-fir to slowly (>90 years) recolonize sites in the western Cascade Range 400 to 500 years ago. Findings show that long distances from seed sources could have contributed to the slow development of regional old-growth Douglas-fir stands after catastrophic dis- turbances, but not repeated disturbances during stand develop- ment, and not competition from shrubs and hardwoods. The find- ings also suggest an AD 2020-2160 timeline for natural refores- tation of the Mount St Helens National Volcanic Monument. [Abstract from: Yamaguchi, D.K. 1993. Forest history, Mount St Helens. Research & Exploration - A Scholarly Publication of the National Geographic Society, 9(No. 3 - Summer 1993): 294-325.] REPORTS ON POISONING BY GIANT HOGWEED, HERACLEUM MANTEGAZZIANUM From: Medline Andrews, A.H., Giles, C.J., Thomsett, L.R. 1985. Suspected poisoning of a goat by giant hogweed. Vet-Rec. 116(8): 205-7. A five-year-old male African pygmy goat became ill four weeks after transfer from a zoological garden to a municipal park. The animal was subdued, refused to eat and drink and showed profuse salivation. Examination of the mouth revealed severe ulceration. The condition gradually responded to nursing and supportive therapy. Circumstantial evidence suggested the possibility that the lesions were caused by giant hogweed (Heracleum mantegazzianum). Supportive evidence that the plant could produce lesions was provided by the application of a cut stem to the hard palate and a solution of various dilutions to clipped areas of the backs of two ewes. Both ewes produced reddened skin when the concentrated solution was applied and both showed marked reddening of the gingival mucosae and in one animal small ulcers developed in the rostral part of the mouth. It is sug- gested that H. mantegazzianum may be a potential hazard for grazing ruminants. Pira, E., Romano, C., Sulotto, F., Pavan, I., Monaco, E. 1989. Heracleum mantegazzianum growth phases and furocoumarin content. Contact-Dermatitis 21(5): 300-3. The observation of photocontact dermatitis from Heracleum man- tegazzianum Sommier et Levier in 2 gardeners at work prompted the analysis of furocoumarin content of stem, leaves and fruits of the plant during a period of 1 year. Their concentration was found to be maximal in fruit, intermediate in leaf, and minimal in stem. Psoralen was the most prevalent substance in the leaf and bergapten in the fruit. In the stem, in contrast, individual furocoumarins were found in lower but variable concentrations. 3 furocoumarin seasonal peaks were observed in the leaf: the maximal peak occurred in June, the intermediate in August, the minimal in November. This trend corresponds to 3 biological phases of the weed. Ippen, H. 1984. [Photodermatitis bullosa generalisata] Derm- Beruf-Umwelt. 1984; 32(4): 134-7. [German] Two observed cases indicate atypical forms of phyto- photodermatitis. Unusual localisations or generalized outbreaks have to be taken into account in cases of sunbathing without clothes on. Power lawn mowers with rotating blades spread Heracleum and other phototoxic juices via freshly cut grass, causing diffuse - as opposed to striped - manifestations on the uncovered skin areas. The most certain prevention of such a reaction is to known which few plants are responsible for phyto- photodermatitis and to avoid them in sunny weather. The plants should by no means be exterminated, even those (such as Heracleum mantegazzianum, "giant hogweed") which have a tendency to spread. Further references: Prinz, V.L., Kostler, H. 1976. Ein Bericht uber 3 Falle von toxischer Phytophotodermatitis durch Heracleum mantegazzianum (Riesenherkulesstaude). Dermatol-Monatsschr. 162(11): 881-6. Camm, E., Buck, H.W., Mitchell, J.C. 1976. Phytophotodermatitis from Heracleum mantegazzianum. Contact-Dermatitis. 2(2): 68-72. HAPPY NEW YEAR ! VSE NEJLEPSI V NOVEM ROCE !

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