New Vascular Plant Records on Pelee and East Sister Islands, Essex County, Ontario Craig A. Campbell' and A. A. Reznicek^ 1421 King Street North. Waterloo, Ontario N2J 3Z4 ^Department of Botany, Erindale College, University of Toronto, Mississauga, Ontario L5L 1C6 Campbell, C. A. and A. A. Reznicek. 1977. New vascular plant records on Pelee and East Sister Islands, Essex County, Ontario. Canadian Field-Naturalist 92(1): 384-390. Pelee Island, the southernmost part of Canada, has a diverse and very interesting flora containing many species rare or absent elsewhere in Canada. Reported as new to Canada are seven species of vascular plants: Carex davisii, Care.x divulsa subsp. leersii, Sedum telephioides. Euphorbia obiusala, Myosotis macrosperma, Lycopus virginicus var. virginicus, and Senecio glabellus. These are briefly discussed. In addition, we report on the status of 13 very rare species known previously from the area: Camassia scilloides, Spiranthes magnicamporum, Celtis tenuifolia, Chenopodium foggii, Thalictrum dasycarpum. Corydalis flavula. Cydonia oblonga, Ammannia coccinea, Chaerophyllum procumbens, Phacelia purshii, Conobea multifida, Eupatorium ahissimum, and Eclipta prostrata. Fifty-five other species that are additions to the published flora of the Erie Archipelago, Pelee Island, and East Sister Island are listed as well. Key Words: vascular plants, floristics, Erie Archipelago, Ontario, Canada, endangered species, phytogeography. Field work on Pelee Island, Essex County, The warm chmate of Pelee Island is largely a Ontario, during the past 1 years has resulted in a result of the moderating effects of Lake Erie; the number of discoveries of considerable floristic mean annual temperature is 9.6° C (49.3° F), interest. Several species not previously reported several degrees higher than that of the mainland for Ontario or even for Canada have been of Essex-Kent Counties. The average growing recorded, although the Erie Islands have been season (free of killing frosts) is 192 days. quite extensively botanized (Macoun 1893; Core Droughty conditions do occur as a result of 1948; Duncan 1973). lighter rainfall than on the mainland (Core The first botanist to collect extensively on 1948). Pelee Island has relatively low rainfall, Pelee Island was John Macoun, Canadian shghtly under 75 cm (30 in) per year. Dominion Botanist, in 1882 (Macoun 1893). The flora of Pelee Island has strong affinities Later came C. K. Dodge, who produced the first with the Ohio-Mississippi River lowlands, and list of Pelee Island plants (1914), and then Core this affinity is reflected by some of the most (1948). The collections of Wilfred Botham, of abundant trees on the island, e.g., Celtis Occi- Cottam, Ontario were largely the basis for dent alis, Acer nigrum, Fraxinus quadrangulata, Boivin's (1953) additions to Core's hst. Recent Quercus macrocarpa, and Populus deltoides. work by Stuckey (1968), Duncan and Stuckey The north shore of Ohio was mapped as having (1970), and Duncan (1973), as well as by Stuckey small prairie outliers by Transeau(1935); prairie and Duncan, currently updating the work of species are fairly well represented on Pelee Core, has added considerably to the published Island. Also, owing to its floristic affinities with flora. Our paper reports species in addition to the mid-west, Pelee Island, and especially the those recorded in these lists. southern points of it (Figure 1) are much more Pelee Island in particular has a wide diversity similar to Point Pelee than to the Niagara of plant habitats and a large flora for such a small Peninsula, despite the limestone bedrock. Few area. The island is situated in the western end of elements of the eastern Carolinian and/ or Lake Erie, in extreme southern Canada between Appalachian flora occur on Pelee Island; the 41°43' to 41°50'N, and 82°37' to 82°42'W. It is Tulip-tree {Liriodendron tulipifera) and Mag- the largest of the Erie archipelago islands: 4083 h nolia acuminata, for example, are missing from (10085 acres). East Sister Island, also part of the Erie Islands. The flora of these islands is of Pelee Township, is approximately 13 km (8 mi) continual interest because of the southern species west of Pelee Island, at 41°49' N, 82°50' W; it is which seem to shift northward and thus first some 26 h (65 acres) in size, of which only about reach Canada on this archipelago. 14.6 (36) have been above water recently. Because of the warm cUmate of Pelee Island, 384 1977 Campbell and Reznicek: Vascular Plant Records, S.W. Ontario 385 and East Sister Islands and including whether the species are new to the flora of the Erie Archipelago is also included. Our major collecting sites are shown in Figure 1 ; others are specified in the annotated list which follows. Habitats are briefly noted; more details in connection with the present paper can be obtained from the Canadian Botanical Association's Survey of the Rare and En- dangered Plants of Canada. Annotated List of Species New to Canada Carex davisii Schwein. & Torr. Essex County, 9.6 km (6 mi) northeast of Amherst- burg along Canard River, occasional at edge of deciduous woods, 24 June 1955, Calder and van Rens 15928 (DAO,TRT) (sub C. formosa). Pelee Island, Mill Point, south side of main E-W road, edge of woods and cultivated field, 28 June 1975, Campbell and Harris (TRTE, WLU). This southern and mid-western species of lowland woods and meadows was previously recorded from nearby South Bass and Kelley's Islands, Ohio (Core 1948) and sparingly from extreme southern Michigan (Voss 1972). The report of this species from Quebec (Marie-Victorin 1935) has been shown to be an error Figure L Map of Pelee Island showing major collecting locations. by Rouleau (1964). Carex divulsa Stokes subsp. leersii (Aschers & several cultivated species which persist and Graebn.) W. Koch + leersiana Rauschert, slowly spread on Pelee Island do so rarely or not (C polyphylla Kar. Kir., C. C leersii F. W. Schultz). Along South Road at elsewhere in Canada. These have not been junction with Stone Road just west of Mill Point, discussed in the list. They include Rosa multi- Pelee Island, 8 August 1974, Reznicek, Campbell and flora, Lonicera japonica, and Prunus persica. Donaldson (TRTE). flora is also The of Pelee Island somewhat A Eurasian sedge, C. divulsa subsp. leersii prefers paralleled by the fauna. The Small-mouthed calcareous soil (Jermy and Tutin 1968), as is the case Salamander {Ambystoma texanum), the Blue on Pelee Island. The taxonomic status of the Carex Racer {Coluber constrictorfoxi), the Red-bellied muricata aggregate, to which this species belongs, is Woodpecker (Melanerpes carolinus), and Blan- not yet fully clear. We follow here the nomenclature chard's Cricket Frog (Acris crepitans blan- proposed by David and Chater (1977). Further discussion of this difficult complex of species is chardi) occur in Canada as well established provided by Jermy and Tutin (1968), David and populations on Pelee Island only. These species Kelcey ( 1 974), and David ( 1 976). Complete synonomy are widespread in the central Mississippi-Ohio is listed in David (1976). lowlands, but very rare or absent elsewhere north Sedum telephioides Michx. of the international boundary. Pelee Island, Verbeek savanna, dry limestone Our floristic additions are recorded in the outcrop, pasture, 4 September 1974, Campbell and form of an annotated list, dealing first with Donaldson (WLU). vascular plants to Canada, and second with new This species was growing with Corydalis flavula in recent observations of rare species. short dis- A open rocky savanna. Since it was observed growing cussion of the floristic and phytogeographic here close to houses, it may well be an escape from significance of each species is provided. A table cultivation. It was not reported for the Erie Islands by summarizing other additions to the flora of Pelee Core (1948) and Boivin (1953). Its native range is to 386 The Canadian Field-Naturalist Vol. 91 the south of Lake Erie (Clausen 1975), and it has not Gleason and Cronquist ( 1 963). Stuckey ( 1 975) records been previously reported from Canada. it as rare and local on the American Erie Islands and, in particular, in Perry's Monument Marsh on South Euphorbia obtusata Pursh Bass Island, where he considered it adventive from Essex County, River Canard, 17 June 1972, W. farther south. Botham (in herb. W. Botham). Pelee Island, Verbeek's, Harris Road (north side), Recent Records of Rare Plants open oak savanna (grazed), 9 June 1974, Campbell Camassia scilloides (Raf.) Cory Wild Hyacinth and Donaldson (CAN, WLU). Pelee Island, Brown's (Middle) Point, low rich open This is the first substantiated report of this species deciduous woods, 10 May 1974, Donaldson and for Canada. Soper's (1949) listing of this species from Campbell P74-1 (CAN); and Fish Point, wet hedge- southern Ontario was based on the report by Billings row, 7 August 1974, Campbell, Reznicek and Donald- (1862) (J. H. Soper, personal communications 1976). son (WLU). Billings' report was based upon a specimen of E. Although this lovely spring lily was known from wet platyphylla (Dore 1961). It is recorded by Gleason and meadows on White Island in the Detroit River near Cronquist (1963) from Pennsylvania to Indiana. Amherstburg (1 1 June 1882, J. Macoun, CAN), it has been recently collected in Canada only on the Erie Myosotis macrosperma Engelm. (M. virginica var. Islands including Hen, Middle Sister, macrosperma (Engelm.) Fern.) and North Harbour (Core 1948) and Middle Island (9-10 May Pelee Island, Fish Point, woodland, 7 June 1970, 1939, H. Senn 1128 and J. H. Soper, TRT). This plant J. K. Morton (WAT). Pelee Island, Brown's (Middle) is vulnerable to picking and grazing and should be Point, low woods, 7 June 1974, Campbell (CAN, WLU). protected, or its extinction in Canada is probable.