| BEN |
| BOTANICAL ELECTRONIC NEWS |
|---|
| ISSN 1188-603X |
| No. 370 January 11, 2007 | aceska@telus.net | Victoria, B.C. |
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Born in Kit Carson, Colorado on November 30, 1935, Ed Oswald passed away peacefully in Kelowna on Dec 1, 2006 with his family by his side.
Ed spent two years in college before joining the Navy for four years. He returned to College and received his B.Sc. in 1962 and his M.Sc. in 1963 from the Western State College in Gunnison, Colorado and his Ph.D in 1966 from the Montana State University in Plant Ecology. The title of his Ph.D. thesis was: A synecological study of the forested moraines of the valley floor of Grand Teton National Park, Wyoming.
Ed Oswald worked at the Pacific Forestry Centre in Victoria from 1970 until his retirement in the mid-1990s, and had also spent three years at the Canadian Forest Service lab in Winnipeg before the lab closed. Throughout his career at Victoria, he provided ecological data from various locations throughout British Columbia to research studies; his greatest contribution and the work period he enjoyed most, however, was the time he spent in Yukon Territory, which culminated in a publication in the land- classification field. Oswald served on a number of national and regional committees and represented the Canadian Forest Service in the Mackenzie Pipeline Hearings.
The list of Ed Oswald's Pacific Forestry Centre publications is available at the following web site: http://bookstore.cfs.nrcan.gc.ca/Searchpubs_e.php?AuthorIDs=AU14298
Ed was a long time member of the Victoria Curling club and was a member of Gallagher's Golf and Country Club in Kelowna. He was passionate about making homemade wine and loved sharing and comparing with his homemaker's wine club. Above all, gardening was his greatest passion. Ed and his wife, Lorna were avid square dancers and loved traveling. Winters were spent at their timeshares enjoying the sunshine in many different locations.
Although the abundance of Phragmites has increased drammatically in North America over the past 150 years, it was only recently that this was attributed to introduction of an aggressive non-native race (e.g. Saltonstall 2002, Catling et al. 2003). Of the two taxa that occur in Canada, the native one has been differentiated as Phragmites australis (Cav.) Trin. ex Steud. subsp. americanus Saltonstall, P.M. Peterson and Soreng (Saltonstall et al. 2004). The introduced plants, identified as such according to criteria presented by Robichaud & Catling (2003), Saltonstall et al. (2004) and Catling et al. (2006), have been referred to Phragmites australis (Cav.) Trin. ex Steud. subsp. australis because:
With regard to both (1) and (2), Phragmites australis (Cav.) Trin. ex Steud. subsp. australis is the only species recently recognized in Europe (e.g. Tutin 1980) with the exception of the very distinctive P. frutescens H. Scholz with vegetatively proliferating spikelets (Greuter & Scholz 1996). Despite the fact that P. australis is based on material from Australia, Clayton (1967) reported that the Australian and European plants were conspecific. The halophytic race of southern Europe, sometimes differentiated as Phragmites australis subsp. altissimus (Benth.) Clayton, also known as Phragmites communis subsp. maximus Clayton and Phragmites isiaca Kunth, has been segregated in the past, but is said to intergrade with subsp. australis, to the extent of being unworthy of recognition (Clayton 1967, Tutin 1980, Clevering & Lissner 1999).
As it stands there is no current world monograph with which taxa of Phragmites can be conveniently identified and it is clear that the infrageneric classification requires more study. However, using the literature available it is possible to arrive at the following conclusions: Four species are currently recognized and as noted by Saltonstall et al. (2004), all temperate subspecies and varieties are included under P. australis (see also Clayton 1968 and Clevering & Lissner 1999). Thus any North American plant that is not subspecies americana is likely referable to subspecies australis provided that no other infrataxa are recognized (as appears to be the case, see above).
Considering the four species that are currently known, and excluding Phragmites frutescens which is presumably better treated as a variety or even a form, the alien plants in Canada appear to conform to P. australis. They have blades that are smooth, or slightly rough when dry, but not scabrous beneath, and the rachilla hairs are 6-10 mm long rather than 4-7 mm, and upper glumes more than, instead of less than, 5 mm long. Thus they are not referable to the tropical P. mauritianus Kunth or P. karka (Retz.) Trin. ex Steud. (Clayton 1967, Allred 2003, Liang & Phillips 2006). This leaves P. australis and P. japonicus Steud. The latter differs from P. australis in having lower glumes longer than 2 the length of the lowest lemma (instead of shorter), in having stolons zigzag (instead of straight), and in having stolon nodes hirsute instead of glabrous (Liang & Phillips 2006). With lower glumes less than 2 the length of the lowest lemma, stolons essentially straight, and stolon nodes glabrous in a few observed, the alien plants in Canada are not P. japonicus but rather P. australis. The text in both Liang and Phillips (2006) and Ohwi (1965) notes that the culms of P. australis (sub P. communis Trin. in Ohwi) can be either glabrous or pilose, as suggested by examination of specimens from Europe and Asia (pers. obs.). Thus the presence of pilose nodes in some of the alien Canadian plants does not make them referable to P. japonicus. Furthermore Phragmites japonicus is a species with relatively smaller spikelets 8-12 mm long whereas in P. australis, the spikelets are 10-18 mm long (Liang & Phillips 2006). In the invasive alien Canadian plants the spikelets are 10-16 mm long (measured from the base of the first glume) placing them with P. australis. Ohwi (1965) also notes that in P. japonicus the upper sheaths are usually dull purplish above which is not true for the alien plants in Canada. Considering the preceding and assuming that one wants to recognize the North American native subsp. americanus, the alien plants in Canada, and presumably elsewhere in northern North America, are referable to P. australis subsp. australis.
Invasive aliens have become a major threat to biodiversity and to human health and economy. In order to deal with the problem, databases on invasive alien plants and animals have been highlighted as an urgent need in Canada and around the world. With support from the Federal Biodiversity Information Partnership, staff of the AAFC vascular plant herbarium recently completed a database on the occurrence of native and alien races of Common Reed (Phragmites australis) in Canada.
The introduced Phragmites australis (Cav.) Trin. ex Steud. subsp. australis has been recently recognized as a the top priority invasive alien plant of natural habitats in Canada (Catling 2005, Catling & Mitrow 2005), and in parts of the United States (Marks et al. 1993, 1994, Blossey 2002). It has also recently invaded cropland. The native subsp. americanus Saltonstall, P.M. Peterson and Soreng is rare and localized in parts of its North American range and is a priority for protection in some areas. Information on both of these species is urgently needed and a database for Canada is now available.
This database can be accessed at the Canadian Biodiversity Information Facility Website: http://www.cbif.gc.ca/
Select "language", then "Species Access", then "Plants", then "Search by Taxonomic Name", then enter either the genus name "Phragmites" or the name of the native taxon "Phragmites australis subsp. americanus" or the name of invasive alien taxon "Phragmites australis subsp. australis" and select the Phragmites database below. Then click "search" and wait a few minutes until the database is loaded. A list of specimens with complete label data follows. It includes either 1679 records for the entire database (both subspecies and specimens that cannot be assigned to subspecies) or 901 for subsp. americanus or 275 for subsp. australis. At the bottom of the specimen list there is an option to create a map which can be enlanged and within which the data points can be queried. The database can also be searched by collector and location and there is a link to other information on Phragmites in the Integrated Taxonomic Information System.
The entire database includes 1679 specimens and is based on material in 20 herbarium collections and museums across Canada including ACAD, ALTA, CAN, DAO, MMMN, MT, MTMG, NSPM, QFA, QUE, SASK, TRT, TRTE, UBC, UNB, UPEI, UWO, V, WAT, and WIN (acronyms from Holmgren et al. 1990 and Holmgren 2005).
Research, some of which is published (Robichaud and Catling 2003, Saltonstall et al. 2004, Catling 2006) has established that subsp. americanus differs from subsp. australis in having shorter first glumes and that glume length is strongly correlated with colour of lower stem internodes. Older collections and those from native habitats consistently have red lower internodes suggesting that this is characteristic of the native subspecies. In preparing the database all specimens with clearly red or reddish- purple lower stem internodes were refered to subsp. americanus, whereas all specimens with yellow internodes were referred to subsp. australis. Specimens without bases, of which there are many because plant collectors frequently collect only the reproductive portion of these tall plants, were identified using the following key which is based on a bimodal distribution of maximum lower glume length correlated with stem colour.
Using the lower glume limit of 4.3 mm, the misclassification rate is approximately 6.7%. However, other limits can be selected by assigning individuals in the overlap zone to the to the category of unknowns and this was done for identification of specimens in the database. All plants with lower glumes under 3.8 mm long were assigned to subsp. australis, with the result that 0.3 % of subsp. americanus would be misidentified. All specimens with lower glumes over 4.2 mm long were assigned to subsp. australis which would result in 6.6 % of plants possibly referable to subsp. australis being misclassified. However, these misclasification rates may be based on rare mutants lacking red pigment or to hybrids. This method results in 15.8 % of specimens with only inflorescences being unidentified (as a result of occupying the overlap zone). Other characters may also be useful in distinguishing the two subspecies, such as height of ligules (Saltonstall et al. 2004), but these characters have yet to be tested using a large sample.
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