From aceska at telus.net Thu Sep 13 00:18:44 2007 From: aceska at telus.net (Adolf Ceska) Date: Wed, 12 Sep 2007 16:18:44 -0700 Subject: [BEN-L]BEN # 381 Message-ID: <003d01c7f593$4408bf10$2470b440@xphome> =20 BBBBB EEEEEE NN N ISSN 1188-603X BB B EE NNN N =20 BBBBB EEEEE NN N N BOTANICAL BB B EE NN NN ELECTRONIC BBBBB EEEEEE NN N NEWS No. 381 September 12, 2007 aceska@telus.net Victoria, B.C. ----------------------------------------------------------- Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2 ----------------------------------------------------------- BOTANY BC, 2007 OSOYOOS MAY 10 to MAY 13, 2007=20 >From Chris Pielou and Sharon Niscak, Comox This year's Botany BC was held in Osoyoos, from 10 -13 May. =20 Headquarters was the Spirit Ridge Resort and the adjacent Nk'Mip=20 Desert Cultural Centre. Elizabeth Easton masterminded all the=20 planning with her customary skill, she and Terry McIntosh were=20 our hosts. The weather was warm and the sun shone on our two field-trip days, when we split into two groups, each spending a day on each=20 trip.=20 Trip 1. The first part of Trip 1 was led by Mike Miller, and took=20 us up open hillsides overlooking the Similkameen River near=20 Chopaka in the morning. The second part of Trip 1, led by Adolf=20 and Oluna Ceska, took us along the road up Mt Kobau almost to the=20 summit, where germinating _Floerkea proserpinacoides_ and some=20 last year's stalks of _Agastache urticifolia_ were found. When=20 we reached the snow close to the top on Mt. Kobau, Jim Ginns and=20 Oluna Ceska showed us some very interesting snow bank fungi (cf.=20 BEN # 377 April 12, 2007), including _Caloscypha fulgens_,=20 _Cheilymenia fimicola_ (on old cow dung), _Cheilymenia raripila_=20 (on cow dung), _Clitocybe albirrhiza_, _Clitocybe glacialis_, _Discina perlata_, _Erythricium laetum_ (comon snow bank mushroom=20 in WA, not previously collected in British Columbia), and=20 _Peziza_ sp. Trip 2, led by Terry McIntosh, went to exceedingly dry benchlands=20 (cactus and tumbleweed country) east of Highway 27 between=20 Osoyoos and Oliver in the morning; and in the afternoon, to the=20 foot of McIntyre Bluff (overlooking Vaseux Lake) and on to White=20 Lake Grasslands and Haynes Lease. The botanizing was splendid. =20 The low-altitude bench lands of the Okanagan Valley are typically=20 covered with sage-brush (_Artemisia tridentata_), rabbit-brush (_Ericameria nauseosa_), and bluebunch-wheatgrass (_Psudoroegneria spicata_), plus a multitude of attractive flowering herbs. Those in flower included _Erigeron linearis_,=20 _Lithospermum incisum_, _Hydrophyllum capitatum_, _Triteleia=20 grandiflora_, _Calochortus macrocarpus_, _Lewisia rediviva_ and=20 _Balsamorrhiza sagittata_. Mike was also able to show us red- listed _Linanthus septentrionalis_ and blue-listed _Halimolobus=20 whitedii_. The very southern end of the valley, including Osoyoos, has=20 abundant antelope-brush (_Purshia tridentata_) as well as sage- brush which, because it is so much darker, makes for a marked=20 change in the scenery. And with the antelope-brush we saw some=20 of the plants whose range in Canada is restricted to the extreme=20 southern end of the Okanagan valley, such as _Artemisia=20 tripartita_, _Halimolobus whitedii_, _Erigeron poliospermus_ and=20 _Leptodactylon pungens_. These are some of the plants species=20 that give the region its exceptional biodiversity. Other=20 rarities seen by some of our group were two blue-listed snakes:=20 western rattlesnake (_Crotalus oreganus_) and racer (_Coluber=20 costrictor_). They all need the protection that only the planned=20 South Okanagan-Similkameen National Park can provide and that is=20 still not a _fait accompli_. We must write more letters to the=20 Prime Minister and Minister of the Environment (from the informed=20 to the ignorant) to reinforce the letters we sent last year. =20 Besides the field trips we had two interesting and convivial=20 evenings at the magnificent Nk'Mp Desert Cultural Centre. We=20 were welcomed on our first evening by Modesta Stelkia Betterton=20 and Chief Clarence Louie and watched the fascinating film "Coyote=20 Spirit." During the evening we were also treated to the=20 exquisite details of nature with its wondrous geometry via a=20 slide show set to music. Orville Dyer's photography captured=20 the form, light and beauty that surrounds us when we open our=20 eyes and examine the intricacies of our earth. =20 Ted Lea illustrated the use of historical mapping in determining=20 eco-system modification and shifting dynamics by comparing=20 historical photographs, with identifiable landmarks, to present=20 day photographs. Knowledge of the historical context of the=20 earlier photographs is relevant because early settlement was=20 accompanied by practices that changed the environment=20 significantly from pre-contact land use. =20 On our final evening, following a feast of salmon cooked=20 traditionally over a bonfire, the Osoyoos Indian Band Youth=20 Dancers engaged the audience with traditional dancing. =20 Participation by the very young children guided by older=20 teenagers illustrated how cultural inclusiveness is valued in=20 traditional learning. The youngest Botany BC members joined the=20 dancers with energy and joy. =20 Terry Millar presented an entertaining overview of activities in=20 the South Okanagan. For the first time Botany BC honoured the=20 substantial contribution of Oluna and Adolf Ceska to the study of=20 botany. All of us have benefited from the years of dedication,=20 research and botanical support of these remarkable botanists. An=20 entertaining slide show compiled by the Botany BC committee=20 highlighted their achievements. Oluna and Adolf were invited to=20 choose the next location for Botany BC, but they preferred to=20 leave the decision to the whole group. =20 That was Botany BC in 2007-memorable for the beautiful landscapes, flora and fauna. Thank you=20 Elizabeth, Terry, Adolf, Oluna and Mike for organizing this great=20 trip. For Botany 2008, we'll meet at Powell River and plan to=20 visit Savary and Texada Islands. =20 [It was a pity that for quite a few of us our nice memories of=20 BOTANY BC 2007 were marred by a fierce attack of Norwalk virus (_Norovirus_) that troubled about 40 per cent of participants.=20 Let's hope that all of those afflicted will remember the nice=20 botanical moments rather than the negative side of the trip. - AC] BOOK ANNOUNCEMENT: BRYOPHYETS OF COLORADO =20 Weber, W. A., & R. C. Wittmann. July, 2007. _Bryophytes of=20 Colorado. Mosses, Liverworts, and Hornworts. Pilgrims=20 Process, Inc., Santa Fe, New Mexico. 238 p. + 8 Plates. US $29.95. Printed in U.S. and Europe and available=20 from Amazon, Barnes & Noble, and any book store. This is the first comprehensive work on Colorado bryophytes, 401=20 mosses and 106 liverworts and hornworts, compared to 292 (mosses=20 only) reported in Weber (1973) _Guide to the Mosses of Colorado._=20 This is the result of a decade of concentrated field and=20 herbarium work, not to mention over 75 years preparatory studies=20 by the senior author and 20 by the junior. Colorado has been a blind spot in the map of North American=20 bryophytes, and while it has no known endemic species, there are=20 a significant number that are disjunct from the Holarctic region,=20 Middle Asia including western China, the Russian Altai,=20 Turkestan, and Central and South America. The book comprises an introduction outlining the history of=20 bryological collecting, explanation of the scientific names,=20 notes on the people who described the species, keys to the genera=20 and species, citations of significant specimens, a glossary,=20 index by specific epithets, bibliography, and an alphabetical=20 catalog with lists of synonyms that have been applied in earlier=20 papers. Since this is a fairly technical book, we now are beginning to=20 refine our electronic _Moss Primer_ to help beginners to become=20 acquainted with the easily recognizable common species of=20 Colorado. NOTES ON THE IDENTIFICATION OF THE _EUPHORBIA ESULA_ GROUP IN CANADA From: Paul M. Catling, Biodiversity, National Program on=20 Environmental Health, Agriculture and Agri-food Canada,=20 Wm. Saunders Bldg., Central Experimental Farm, Ottawa,=20 Ontario, Canada K1A 0C6 [catlingp@agr.gc.ca ] _Euphorbia esula_ is a major weed of both agriculture and natural=20 landscapes in Canada (Biesboer and Eckardt 1987, Haber 1997).=20 Especially in the prairie provinces it intereferes with=20 agricultural production costing millions in reduced carrying=20 capacity of rangeland, and it also displaces many native species=20 and changes natural habitats. Recently we have received many=20 questions regarding its identification and relationship to other=20 species found in Eurasia and possibly occurring in North America.=20 Development of a database of specimens in Canadian herbaria at=20 DAO required checking of specimen identifications and the=20 following notes were prepared as part of this process. These=20 notes, reproduced below, will satisfy many of the requests for=20 information that we have received, especially regarding=20 identification. Comments and new information are welcome. =20 A brief overview Leafy Spurge is native to Eurasia where it was once divided into=20 numerous species by taxonomists in different countries. In fact=20 more than 60 species have been described in the aggregate. Recent=20 studies have suggested several related species in the group and=20 the recent Canadian study of Crompton et al. (1990) suggested=20 that four taxa occur in North America _E. agraria_ Bieb., _E.=20 cyparrisias_ L., _E. esula_ L., and the hybrid _E_. X=20 _pseudoesula_ Schur. The group of _E. esula_ and its close=20 relatives (within section _Esula_ Dumort.) is distinguished by=20 smooth seeds, raylet leaves not joined at the base, capsules 4-5=20 mm wide, and leaves pinnately veined (Smith & Tutin 1968). The=20 group is probably best conceived as about 7 species (_E.=20 agraria_, _cyparissias_, _esula_, _lucida_, _nevadensis_,=20 _salicifolia_, and _undulata_). There are also 3 hybrids and _E.=20 boissieriana_, the relationships of which are unclear.=20 =09 The last extensive taxonomic study of the group was that of=20 Crompton et al. published in 1990. It contributed some important=20 observations, but much more detailed taxomomic work is needed in=20 this difficult group. Although useful, recent studies have been=20 localized (e.g. Geltman 1996) or general (e.g. Rowe 1997). It is=20 remarkable that the last time substantial taxonomic work was done=20 on this complex, was 17 years ago, yet the need is clear and it=20 is one of the world's worst weeds. =09 Much information has been published on biology, control and=20 impact, both in the scientific and popular literature and on the=20 web (e.g. Best et al. 1980, Haber 1997). Its expansion in Canada=20 occurred mostly after 1933 (see maps in Haber 1997). It continues=20 to invade, at least on a local scale, and has a number of=20 effective seed dispersal mechanisms. Seeds lodge in mud on=20 vehicles and are dispersed by a variety of animals (e.g.=20 Blockstein et al. 1987; Pemberton 1988; Wald et al. 2005). Root- feeding Flea Beetles, including 5 species of _Apthona_, most of=20 which are established across Canada, have proven effective in=20 biological control reducing some infestations by 90%. Since the=20 cost of spraying herbicide to achieve control is excessive, these=20 beetles may already have saved many millions. Another control=20 agent, the Spurge Hawk Moth (_Hyles euphorbiae_) has proven to be=20 a useful control agent as a larvae (e.g., Forward,and McCarty.=20 1980) but may also be beneficial as an adult in pollinating an=20 endangered native orchid (Jordan et al. 2006). It may also be of=20 interest that milky juice of leafy spurge causes a severe=20 dermatitis in some people and the plants are poisonous to most=20 livestock. =20 Annotated list of species occurring in Eurasia, Canada, and the=20 United States (species not reported from Canada are in square=20 brackets, the list includes partial synonymy largely from Smith &=20 Tutin (1968) and Govaerts et al. (2000). A complete list of=20 synonyms and their places of publication may be found in the=20 latter reference.=20 _Euphobia agraria_ Bieb., URBAN SPURGE, (_E. podperae_ Croizat) Widesrpead in southeastern Europe, introduced in North America.=20 In Canada known only from Alberta, where collected at Edgerton=20 and Lonely Lake on the Bow River, Alberta (Crompton et al. 1990).=20 It is also known from the midwestern and notheastern U.S (Kartesz=20 & Meachum 1999). A few varieties requiring more study have been=20 described on the basis of leaf shape (Smith & Tutin 1968). [_Euphorbia boissieriana_ (Woronow) Prokh.] Although sometimes considered a synonym of _E. esula_ (e.g. Davis=20 1982), this taxon was recognized as a species by Govaerts et al.=20 (2000) and Stace et al. (2005). This latter species (and its=20 putative hybrid with _E. esula_) are separated from subsp.=20 _tommasiniana_ by their slightly wider and more acuminate leaves=20 (Stace et al.2005).=20 _Euphorbia cyparissias_ L., CYPRESS SPURGE (_Galarhoeus=20 cyparrisias_ (L.) Small ex Rydb., _Tithymalus esula_ (L.)=20 Hill) There are both diploid and tetraploid races in North America and=20 Europe, but in Ontario some of the diploid plants lack viable=20 pollen (Moore & Frankton 1969).=20 _Euphorbia esula_ L. _sensu lato_ =09 Having examined hundreds of specimens from across Canada, it is=20 concluded that infrataxa should not be recognized as suggested by=20 some recent authors (Crompton et al. 1999, Evans et al. 1991). A=20 single plant may often possess characters of both subspecies (see=20 below). For example an individual plant may have both linear=20 acute and oblanceolate obtuse leaves. Furthermore leaf shape and=20 width appears to vary continuously among individuals and has a=20 normal distribution. The number of rays is at least to some=20 extent related to plant size. Two subspecies have been segregated=20 using the following characters. Notes on these follow the key. 1a. Umbel with 5-9 rays; axillary rays 2-12; leaves linear to=20 lanceolate and acute or subacute _E. esula_ subsp.=20 _tommasiniana_ and _E_. X _pseudovirgata_ and=20 _E_. X _gayeri_] 1b. Umbel with 8-17 rays; axillary rays 8-20; leaves oblanceolate=20 to broadly ovate or obovate and obtuse or emarginate=20 _E. esula_ var. _esula_ (1) subsp. _esula_, LEAFY SPURGE, WOLF'S-MILK =20 (_E. borodinii_ Sambuk, _E. filicina_ Portenschl,=20 _E. imperfoliata_ Vis., _E. intercedens_ Podp., _E.=20 pancicii_ G. Beck, _E. pseudoagraria_ Smirnov, _E.=20 pseudovirgata_ (Schur) Soo, _Galarhoeus esula_ (L.)=20 Rydb., _Tithymalus esula_ (L.) Hill =20 Plants of _E. esula_ with lanceolate instead of=20 oblanceolate leaves have sometimes been segregated as _E.=20 waldsteinii_ (e.g. Stace et al. 2005).=20 =09 (2) subsp. _tommasiniana_ (Bertol.) Kuzmanov, LEAFY SPURGE,=20 WOLF'S-MILK (_Euphorbia esula_ L. var. _uralensis_ (Fisch. ex Link) Dorn, _E. subcordata_ Ledeb., _E.=20 tenuifolia_ Lam., _E. uralensis_ Fisch. ex Link, _E.=20 virgata_ Waldst. & Kit., non Desf., _E.=20 waldsteinii_ (Soj=E1k) Radcl.-Sm., _Tithymalus=20 uralensis_ (Fisch. ex Link) Prokhanov)=20 =20 Although it is identified by its narrow leaves, this=20 character may not have been part of the original concept=20 (Crompton et al. 1990) so that some additional work is=20 required, not only to establish rank, but also to verify=20 the application of the name.=20 =20 This taxon was reported for Canada by Stahevitch et=20 al. (1988) but not in a later publication involving the=20 same author (Crompton et al. 1990) which accounted for=20 all Canadian species. Thus it is presently connsidered=20 not to occur in Canada, but there are periodic=20 references to its occurrence in Saskatchewan based on the=20 report of Stahevitch et al. (e.g. Kartesz & Meachum=20 1999). In the U.S. it is reported from several states in=20 the upper midwest and in the Great Lakes region (Kartesz=20 & Meachum 1999).=20 =09 Some European workers have recently recognized this taxon=20 at the rank of species (E. virgata Waldst. & Kit, e.g.=20 Geltman 1998). It has most recently been recognized at=20 the rank of subspecies (subsp. _tommasiniana_ (Bertol.)=20 Kuzmanov, e.g. Govaerts et al. 2000). In North America it=20 has been treated at the rank of variety (_Euphorbia=20 esula_ L. var. _uralensis_ (Fisch. ex Link) Dorn,=20 _Vascular Plants of Wyoming_ p. 296. 1988, Kartesz &=20 Meachum 1999), Recognition appears unwarranted (see=20 above) but if recognized, varietal rank seems most=20 appropriate and it is desirable to maintain the name currently used in North America. However, it is treated=20 as a subspecies in the recent world list of _Euphorbia_=20 species (Govaerts et al. 2000). =09 _Euphorbia esula_ L. var. _orientalis_ Boiss. was reported=20 from Connecticut by Croizat (1945) under the name"_E.=20 virgata orientalis_." Croizat (1945) thought that it=20 belonged within _E. iberica_ and described it as a taller and stouter plant than _E. virgata_. The latter has most=20 recently been treated as a synonym of _E. esula_ var.=20 _uralensis_ (e.g. Smith & Tutin 1968) and var.=20 _orientalis_ has has been treated as a synonym of _E.=20 virgata_ (Davis 1982). Both are currently treated as=20 synonyms of subsp. _tommasiniana_ (Govaerts et al. 2000). _Euphorbia waldsteinii_ (Soj=E1k) Radcl.-Sm., recognized as the lanceolate-leaved member of the "_esula aggregate_" by Stace et al. (2005), is treated as a synonym of subsp. _tommassiniana_ by Govaerts et al. (2000). =09 _Euphorbia_ X _gayeri_ Borb=E1s & So=F3, a hybrid of=20 _E. cyparissias_ and _E. esula_ subsp. _tommasiniana_ has=20 been reported from from central Europe to Romania. It would be difficult to distinguish since subsp. _tommasiniana_=20 closely resembles _E. cyparissias_.=20 =09 _Euphorbia_ X _pseudovirgata_ (Shur.) Soo, a putative=20 hybrid of subsp. _esula_ and ssp. _tommasiniana_, is treated as a synonym of _E. esula_ var. _esula_ by some recent=20 authors but retained by Govaerts et al. (2000). It is=20 reported from Europe from the region of Poland to Bulgaria.=20 Since the subspecies intergrade, the recognition of this=20 hybrid seems unwarranted. [_E. lucida_ Waldst. & Kit.] SHINING SPURGE, (_Galarhoeus=20 lucidus_ (L.) Rydb., _Tithymalus lucidus_ (L.) Klotzsch and Garcke] =09 Although _E. lucida_ was reported for Canada (at Edgerton,=20 Alberta by Croizat in 1945), the report was rejected by Crompton=20 et al. (1990) since the specimen was misidentified as _E.=20 agraria_. Boivin (1966, 1967) identified _E. lucida_ on the basis=20 or cordate leaves (although he changed his key later (Boivin &=20 Cruise 1978). Plants with cordate leaves are now placed with _E.=20 agraria_ (e.g. Smith & Tutin 1968) so Boivin's reports (and=20 others based on his) for both Alberta and Saskatchewan are=20 discounted. Boivin and Cruise (1978 ms) suggested that the=20 reports _E. lucida_ for Ontario were based on a specimen at TRT=20 correctly assigned to _E. esula_. These earlier erroneous reports=20 may be the basis for more recent listings for the province. This=20 species has also been reported from three states in the=20 northeastern U.S. (Kartesz & Meachum 1999). It is native to=20 central and southeastern Europe (Smith and Tutin 1968). [_E. nevadensis_ Boiss. & Reuter]=20 =09 A species closely related to _E, agraria_ but smaller (leaves less than 30 mm long instead to 80 mm). It occurs in southern and eastern Spain.=20 _E_. X _pseudoesula_ Schur, HYBRID CYPARISSIAS AND ESULA (?_E_. X _figertii_ Dorfler) This hybrid of _E. esula_ var. _esula_ and _E. cyparissias_, well=20 known in Europe. It was first reported from North America by=20 Moore and Frankton (1969) from the counties of Huron, Bruce and=20 Muskoka in Ontario. It is most easily recognized as a plant that=20 appears to be _E. esula_ but has unusually numerous and crowded,=20 and small leaves (cauline leaves less than 4 cm long and less=20 than 5 mm wide). Moore and Frankton (1969) found only hybrids=20 between diploid _E. esula_ and tetraploid _E. cyparissias_, the=20 hybrid having a chromosome number of 2n=3D50. Since two expressions=20 of the hybrid occur in Europe, one possibly involving a diploid=20 race of _E. cyparissias_ with viable pollen, and since the=20 Canadian hybrids form a small amount of seed (Moore & Frankton=20 1969) possibly allowing backcrossing, there may yet be more=20 variation in this hybrid in Canada than has currently been noted. =09 [_E. salicifolia_ Host], WILLOW-LEAVED SPURGE] =09 Known in Europe from Austria to Turkey. [_E. undulata_ Bieb.], UNDULATE-LEAVED SPURGE] =09 A native of S.E. Russia and W. Kazakhstan Key to the species of the Euphobia esula group occurring in Canada, United States and Eurasia (Species not reported from=20 Canada are in square brackets). Additional taxonomic research is needed to improve this key.=20 1a. Leaf cordate (lobed) at the base 2 1b. Leaf base not cordate 3 =20 2a. Leaves to 30 mm long [_E. nevadensis_] 2b. Leaves to 80 mm long _E. agraria_ 3a. Plants pubescent and with ovate or ovate-lanceolate leaves=09 [_E. salicifolia_]=20 3b. Plants glabrous or if pubescent with linear to linear-lanceolate leaves; 4 4a. Leaves emarginate, oblanceolate or elliptic-obovate, with undulate margins; plants rhizomatous [_E. undulata_] 4b. Lacking the combination of characters in 4a,=20 leaves emarginate or not, oblanceolate or not, lacking=20 undulate margins; plants rhizomatous or not 5 5a. Leaves shiny [_E. lucida_] 5b. Leaves dull 6 5a. Leaves lanceolate and acuminate [_E. boisseriana_] 5b. Leaves linerar, lanceolate, oblanceolate, broadly ovate, obovate, and acute or emarginate =09 6a. Leaves lanceolate to broadly ovate, mostly more than 4 mm=20 wide; lateral branches with few with scattered leaves =09 E. esula sensu lato (for notes on subspecies see above)=20 6b. Leaves linear, less than 4 mm wide; many lateral branches with crowded leaves 7 7a. Cauline leaves less than 2.6 (3) mm wide; floral leaves=20 4-6 mm long E. cyparissias and [_E_. X _gayeri_] 7b. Cauline leaves more than 2.6 mm wide; floral leaves=20 10-13 mm long _E_. X _pseudoesula_ LITERATURE CITED Best, K.F., G.G. Bowes, A.G. Thomas and M.G. Maw. 1980. The biology of Canadian weeds 39. _Euphorbia esula_ L. _Can. J. Plant Sci._ 60: 651-663. Biesboer, G.G. and N. Eckardt. 1987. Element Stewardship=20 Abstract for leafy spurge (_Euphorbia esula_). The Nature Conservancy, Minneapolis. 17 p.=20 Blockstein, D.E., B.D. Maxwell and P.K. Fay. 1987. Dispersal of leafy spurge seeds (_Euphorbia esula_) by Mourning Doves=20 (_Zenaida macroura_). _Weed Technology_ 1(4): 314-318. Boivin, B. 1967. Flora of the prairie provinces, part 1.=20 _Phytologia_ 15(6): 121-159.. Boivin, B. 1966. =C9num=E9ration des plantes du Canada, II -=20 Lignid=E9es. _Naturaliste Can._ 93: 371-437.=20 Boivin, B. and J.E. Cruise. 1978. _The spurges of Canada_.=20 Agriculture Canada, manuscript. 223 p. =20 Croizat, L. 1945. "_Euphorbia esula_" in North America.=20 _American Midland Naturalist_ 33: 231-243. Crompton, C.W., A.E. Stahevitch and W.A. Wojtas. 1990.=20 Morphometric studies of the _Euphorbia esula_ group=20 (Euphorbiaceae) in North America. _Can. J. Bot._ 68: 1978- 1988. Davis, P.H., J.R. Edmondson, R.R. Mill and K. Tan. 1982. _Flora of Turkey and the east Aegean Islands_, vol. 7. Edinburgh University Press. 947 p.=20 Forward, J.R and M.K. Mc Carty. 1980. The control of Leafy=20 Spurge, _Euphorbia esula_, in Nebraska, USA, with the Spurge=20 Hawk Moth, _Hyles euphorbiae_. _Weed Science_ 28(3): 235-240.=20 Geltman, D.V. 1998. Taxonomic notes on _Euphorbia esula_ (Euphorbiaceae) with special reference to its occurrence in the east part of the Baltic region. _Ann. Bot. Fennici_ 35:=20 113-117. Govaerts, R., D.G. Frodin, and A. Radcliffe-Smith. 2000. _World Checklist and Bibliography of Euphorbiaceae (and=20 Pandaceae)._ Part 2. Kew: Royal Botanic Gardens, Kew. Pp. 417-921.=20 Haber, E. 1997. _Invasive exotic plants of Canada Fact Sheet=20 No. 9._ Environment Canada 19 p.=20 See also Leafy Spurge, _Euphobia esula_ at=20 http://www.cws-scf.ec.gc.ca/publications/inv/p9_e.cfm Jordan, C.A., G.M. Fauske, M.O. Harris, and D. Lenz. 2006.=20 First record of the spurge hawkmoth as a pollen vector for=20 the western prairie fringed orchid. _Prairie Naturalist_=20 38(1): 148-159. Kartesz, J.T. and C.A. Meachum. 1999. _Synthesis of the North American flora._ Version 1.0. Biota of North America=20 Program, University of North Carolina, Chapel Hill. Moore, R.J. and C. Frankton. 1969. _Euphorbia_ X _pseudo-esula_=20 (_E. cyparissias_ X _E. esula_) in Canada. _Canadian Field Naturalist_ 83(3): 243-246. Pemberton, R.W. 1988. Myrmecochory in the introduced range weed, Leafy Spurge, _Euphorbia esula_. _American Midland Naturalist_ 119(2): 431-435.=20 Rowe, M.L., D.J. Lee, S.J. Nissen, B.M. Bowditch and R.A.=20 Masters. 1997. Genetic variation in North American leafy spurge (_Euphorbia esula_) determined by DNA markers. _Weed=20 Science_ 45(3): 446-454.=20 Smith, A.R. and T.G. Tutin. 1968. 7. _Euphorbia_ L. Pp.=20 213-226 in T.G. Tutin et al., _Flora Europaea, volume 2,=20 Rosaceae to Umbelliferae_. Cambridge University Press. Stace, C., R. Vander Meijden (ed.) and I. de Kort (ed.). 2005.=20 Interactive flora of NW Europe. A World Biodiversity Database Project based on a DVD-ROM accessed at=20 http://nlbif.eti.uva.nl/bis/flora.php?selected+beschrijving=20 menuentry=3Dsoorten&id+3109 (based on Stace, C.A., 1997. _New Flora of the British=20 Isles._ 2nd Edition. Cambridge University Press. XXVII +=20 1130 p.) Stahevitch, A.E., C.W. Crompton, and W.A. Wojtas. 1988.=20 Cytogenetic studies of leafy spurge, _Euphorbia esula_, and=20 its allies (Euphorbiaceae). _Can. J. Bot._ 66: 2247-2257. Stahevitch, A.E., C.W. Crompton and W.A. Wojtas. 1988.=20 Biology of Canadian weeds. _Euphorbia cyparrisias_ L. _Can J.=20 Plant Science_ 68: 175-191. Wald, E.J., Kronberg, S.L., Larson, G.E. and Carter-Johnson, W. 2005. Dispersal of Leafy Spurge (_Euphorbia esula_ L.) seeds in feces of wildlife. _American Midland Naturalist_=20 154(2): 342-357. ________________________________________________________________ Subscriptions: http://victoria.tc.ca/mailman/listinfo/ben-l Send submissions to aceska@telus.net BEN is archived at http://www.ou.edu/cas/botany-micro/ben/ ________________________________________________________________