4.0 INFORMATION SOURCES
4.1 References

Alex, J.F., R. Cayouette, and G.A. Mulligan 1980. Common and botanical names of weeds in Canada. Research Branch, Agriculture Canada, Ottawa. Publication 1397. 132 pp.

Argus, G.W. and K.M. Pryer. 1990. Rare vascular plants in Canada-our natural heritage. Canadian Museum of Nature, Ottawa. 191 pp.

Argus, G.W. and C. Keddy, eds. 1984. Atlas of the rare vascular plants of Ontario. Part 3. National Museum of Natural Sciences.

Argus, G.W. and D.J. White. 1978. The rare vascular plants of Alberta. Syllogeus 17.47 pp.

Bouchard, A., D. Barabé, M. Dunmais, and S. Hay. 1983. The rare vascular plants of Quebec. Syllogeus 48.75 pp.

Cabin, R.J.,J. Ramstetter, and R.E. Engel. 1991. Reproductive limitations of a locally rare Asclepias. Rhodora 93:1-0.

Crolla, J.P. and J.D. Lafontaine. 1996. Status report on the Monarch Butterfly (Danaus plexippus) in Canada. Canadian Wildlife Service. 24 pp. Unpublished report.

Dore, W.G. 1994. White-flowered form of Asclepias syriaca. Rhodora 46:387.

Doyon, D. 1958. Etude de la distribution géographique de l' asclépiade commune (Asclepias syricaca L.) en Amérique due Nord. 40e rapport de la Société de Québec pour la Protection des Plantes, pp. 91-113.

Erskine, J. S. 1960. Flora of Prince Edward Island. Canada Department of Agriculture Publication No. 1088.

Fox, W.S. 1944. Botanical field notes-summer of 1943. Canadian Field-Naturalist 58:10-11.

Gleason, H.A. 1968. The new Britton and Brown Illustrated Flora of the Northeastern United States and Canada. 3 vols. New York, Hafner Press.

Gleason H.A. and A. Cronquist. 1963. Manual of vascular plants of northeastern United States and adjacent Canada. Van Nostrand Reinhold Co., New York. 810 pp.

Groh, H. 1943. Notes on common milkweed. Scientific Agriculture 23:625-632.

Groh, H. and W.G. Dore. 1945. A milkweed survey in Ontario and adjacent Quebec. Scientific Agriculture 25:463-48l.

Haber, E. and Members of the Subcommittee for Vascular Plants, Mosses, and Lichens. 1995. Guidelines for the preparation of COSEWIC Status Reports on vascular plants, mosses, and lichens. Committee on the Status of Endangered Wildlife in Canada (COSEWIC), Ottawa. 16pp.

Hill, G.a. 1959. A ready reference to the description of the Land of Ontario and its productivity. Department of Lands and Forests.

Hinds, H. 1986. Flora of New Brunswick. Primrose Press, Fredericton. 460 pp.

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. Second edition. Volume 1-checklist. Biota of North America Program and the North Carolina Botanical Garden. Timer Press, Portland, Oregon. 622 pp.

Kephart, S.R. 1981. Breeding systems in Asclepias incarnata L., A. syricaca L.; and A. verticillata L. American Journal of Botany 68:226-232.

Kephart, S.R. and C.B. Heiser, Jr. 1980. Reproductive isolation in Asclepias: lock and key hypothesis reconsidered. Evolution 34:738-746.

Kingsbury, J.M. 1964. Poisonous plants of the United States and Canada. Prentice-Hall Inc., New Jersey. 626 pp.

Logie, A. 1861. List of plants found growing in the neighborhood of Hamilton, during the years 1859 and 1860. Annals of the Botanical Society of Canada 1:90-108.

Maher, R.V., D.J. White, G.W. Argus and P.A. Keddy. 1978. The rare vascular plants of Nova Scotia. Syllogeus 18.38 pp.

Maher, R.V., G.W. Argus, V.L. Harms, and J.H. Hudson. 1979. The rare vascular plants of Saskatchewan. Syllogeus 20.55 pp.+ maps.

Malcolm, S.B., B.J. Cockrell, and L.P. Brower. 1989. Cardenolide fingerprint of monarch butterflies reared on common milkweed,Asclepias syriaca L. Journal of Chemical Ecology 15:819-853.

Marie-Victorin, F. 1995. Flore laurentienne. Troisiéme édition. Mise à jour et annotée par Luc Brouilet et Isabelle Goulet. Les Presses de l'Université de Montréal, Montréal.

Moore, R.J. 1947. Investigations on rubber-bearing plants. V. Notes on the flower biology and pod yield of Asclepias syriaca L. The Canadian Field-Naturalist 61:40-46.

Morton, J.K. and J.M. Venn. 1990. A checklist of the flora of Ontario-vascular plants. University of Waterloo Biology Series #34. 218 pp.

Oldham, M.J. 1994. Natural heritage resources of Ontario: rare vascular plants. Natural Heritage Information Centre, Peterborough. 48 pp.

Oldham, M.J., D. McLeod, W.G. Stewart, and J.M. Bowles. 1991. Preliminary annotated checklist of the vascular plants of Elgin, Middlesex, and Oxford Counties, Ontario Ministry of Natural Resources, Aylmer. 174 pp.

Robinson, F.A. and E. Oertel. 1975. Sources of nectar and pollen, pp. 283-302. In Dadant and Sons (eds). The hive and the honey bee. Dadant and Sons, Hamilton, Illinois.

Roland, A.E. and E.C. Smith. 1969. The flora of Nova Scotia. Nova Scotia Museum, Halifax 743 pp.

Rowe, J.S. 1972. Forest regions of Canada. Canadian Forestry Service. Publication No. 1300. 172 pp.

Scoggan H.J. 1957. Flora of Manitoba. National Museums of Canada. Bulletin 140.

Scoggan, H.J. 1978-1979. The flora of Canada. 4 parts. National Museums of Canada, Ottawa. 1711 pp.

Shannon, T.r. and R. Wyatt. 1986. Reproductive biology of Asclepias exaltata. American Journal of Botany 73:11-20.

Straley, G.B., R.L. Taylor, and G.W. Douglas. 1985. The rare vascular plants of British Columbia. Syllogeus 59. 123 pp. + maps.

The Nature Conservancy. 1988. Element state tracking database, Central Scientific Databases. The Nature Conservancy, Arlington, Virgina, U.S.A. Unpublished database printout.

Urquhart, F.A. and N.F. Urquhart. 1979. Breeding areas and overnight roosting locations in the northern range of the Monarch Butterfly (Danaus plexippus plexippus) with a summary of associated migratory routes. The Canadian Field-Naturalist 93:41-47.

White, D.J. and K.L. Johnson. 1980. The rare vascular plants of Manitoba. Syllogeus 27.52 pp. + maps.

White, D.J., E. Haber, and C. Keddy. 1993. Invasive plants of natural habitats in Canada-An integrated review of wetland and upland species and legislation governing their control. Canadian Wildlife Service, Ottawa. 115 pp.

Wilbur, H.M. 1976. Life history evolution in seven milkweeds of the genus Asclepias. Journal of Ecology 64:223-240.

Wilson, M.F., R.I. Bertin, and P.W. Price. 1979. Nectar production and flower visitors of Asclepias verticilata. American Midland Naturalist 102:23-35.

Woodson, R.E., Jr. 1954. The North American species of Asclepias L. Annals of the Missouri Botanical Garden 41:1-211.

Wyatt, R. 1976. Pollination and fruit-set in Asclepias: a reappraisal. American Journal of Botany 63:845-851.

4.2 Collections Consulted

The following herbaria were consulted for records of Milkweeds in Ontario in 1983. All Ontario specimens from these herbaria were examined by C. Keddy for the Ontario Rare Plant Atlas (Argus & Keddy, 1984). The herbaria at CAN and DAO were also checked in 1996 by the present author for records of rare Ontario Milkweeds received after 1983.

CAN - Canadian Museum of Nature, Ottawa	QFA - Laval University, Montreal.
DAO - Department of Agriculture, Ottawa.	OK - Queens's University, Montreal.
HAM - Royal Botanical Gardens, Hamilton	RPP - Herbarium of Rondeua Provincial Park.
LKHD - Lakehead University, Thunder Bay.	SFS - Sherbrooke University, Sherbrooke.
MT - University of Montreal, Montreal.	TRT - University of Toronto, Erindale College, Toronto.
MTJB - Montreal Botanical Garden, Montreal.	UWO - University of Western Ontario, London.
OAC - Ontario Agricultural College, Guelph.	WLU - Wilfred Lauier University, Waterloo.
PFM - Herbarium of P.F. Maycock, Erindale College, Toronto.