Smooth goosefoot (Chenopodium subglabrum) COSEWIC assessment and status report: chapter 4

Distribution

Global range

Chenopodium subglabrum is found in the prairie provinces of Canada, and south to Utah and Colorado, west to Washington and Nevada, and east to the Dakotas, Nebraska and Iowa in the United States (Figure 2; based on FNA editorial committee 2004). The populations in Manitoba, Washington, Nevada, Utah, Colorado and Iowa appear to be disjunct from the species’ main range (FNA editorial committee 2004). Oregon and Kansas were reported to have C. subglabrum populations in Smith and Bradley (1990) but the herbarium curators at both Oregon State University (Halse pers. comm. 2004) and Kansas State University (Ferguson pers. comm. 2004) confirmed that they have no records of this species in their respective states.

Figure 2. Smooth goosefoot distribution in North America. The shaded areas represent the core areas of the species’ range and the solid dots represent outlier locations.

Figure 2.  Smooth goosefoot distribution in North America. The shaded areas represent the core areas of the species’ range and the solid dots represent outlier locations.

Canadian range

The known locations of C. subglabrum in Canada are given in Figure 3. The extent of occurrence (EO) for this species in Canada was determined by use of computer GIS (Geographic Information System) software. All localities in Alberta and Saskatchewan were included within a convex polygon. The two Manitoba sites are considered as outliers since there are no suitable habitats or populations known within eastern Saskatchewan.

Figure 3. Smooth goosefoot localities in Canada.

Figure 3.  Smooth goosefoot localities in Canada.

Measured in this manner, the EO of C. subglabrum in Canada is approximately 82,000 km². The actual area covered by sand hills and undifferentiated eolian deposits (the preferred habitat of C. subglabrum) in the three prairie provinces south of the 52nd parallel is approximately 8,300 km² (Wolfe, 2001). No C. subglabrum specimens have been found north of the 52nd parallel.

The area of occupancy (AO) was determined by counting the number of quarter sections (72) where at least one site for C. subglabrum has been found [Note: A quarter-section comprises nearly 65 ha (160 acres)]. The number of sites was multiplied by half the area a quarter section occupies (32 ha or 0.32 km²), as the species was usually distributed over only a portion of a quarter section. The AO of C. subglabrum populations comprises only about 23 km² (72 x 0.32) or about 0.028 % (23/82,000 x 100) of its EO. The actual AO could be larger as dormant seeds of C. subglabrum may occur in the seed bank of stabilized sand hills.

InAlberta, C. subglabrum is represented by widely scattered populations in the southern mixed grassland (Figure 4). Specifically, the populations occur within six different sand hill areas: Grassy Lake (3 populations), Middle (2 populations), Rolling Hills Lake (1 population), Dominion (1 population), Medicine Lodge Coulee (1 population) and Pakowki Lake (1 population) Sand Hills (Figure 4). The Turin site, in the Grassy Lake Sand Hills, is the only one where C. subglabrum occurs with any frequency (Wallis and Wershler 1988). The only population in Alberta that had been visited recently was that in the Dominion Sand Hills (Elchuk pers. comm. 2004).

Chenopodium subglabrum is found in the southwest corner of Saskatchewan from Saskatoon south to Piapot, and from the Alberta border east to Caron (Figure 4). Historically, there were 12 populations in the province: Dundurn (2 populations), Birsay (1 population), Elbow (3 populations), Pelican Lake (1 population), McMahon (1 population), Cramersburg (1 population), Broderick (1 population), Burstall (1 population) and Piapot (1 population) Sand Hills. Additionally, a specimen from Patience Lake collected in 1986, originally identified as C. leptophyllum, was annotated to C. subglabrum in 1995. Thus, in total, there were 13 populations for the province prior to 1992 when the original status report was prepared (Smith and Bradley 1992).

The Beaver Creek site in the Dundurn Sand Hills was revisited every August from 1997-2002 but no plants were observed. Vegetation survey work occurred in the Dundurn Sand Hills at the Biddulph Natural area from 1986-1988 (Pylypec 1989), and at the Whitecap Indian Reservation in June of 2001 (Nelson Dynes & Associates 2001) but no C. subglabrum was observed. The Birsay Sand Hills and Broderick site have been searched at least once in the 1980s (Harms pers. comm. 1992) and in 1995 and 1996 (Robson 1997a) but no plants were found. Dr. Harms considers C. subglarum no longer to be extant at these sites (Harms pers. comm. 1992). The construction of Gardiner Dam in 1967 flooded part of the Elbow Sand Hills and possibly part of the Birsay Sand Hills, which may have destroyed two populations (Wolfe et al. 2002). The McMahon site was visited in 1995 and no individuals were found (Robson 1997a). The vague location description for the site made it difficult to relocate the exact area where the plant had been found in the past. No bare sand or dune habitats were observed in the area (Robson 1997a). The Piapot Sand Hills and Empress site were revisited in 1997 but no plants were found (Lamont and Gerry 1998). However, plants were found at the latter location in 2004 (Elchuk pers. comm. 2004).

Within the last ten years, 18 new C. subglabrum populations have been found in Saskatchewan. Seven populations of C. subglabrum were discovered in the Seward Sand Hills (Robson 1997a, b). In 1997 and 1998 staff at the Saskatchewan Conservation Data Centre conducted surveys for rare plants in various sand dune areas (Lamont and Gerry 1998) and reported finding nine new populations of C. subglabrum in the Bigstick-Crane Lakes (3), Great (5) and Tunstall (1) Sand Hills. Additional populations were also discovered in the Burstall (1) and Dundurn (1) Sand Hills (Elchuk pers. comm. 2004, Lamont and Gerry 1998, Johnson and Weichel Resource Management Consultants 1997). In summary, C. subglabrum has been collected in 11 different sand hill areas in Saskatchewan: Bigstick-Crane Lakes, Birsay, Burstall, Cramersburg, Dundurn, Elbow, Great, Seward, Pelican Lake, Piapot and Tunstall Sand Hills. Sand hills where C. subglabrum has not been found, despite periodic searches include the Antelope, Manitou Lake, Pike Lake and Westerham Sand Hills.

Figure 4. Smooth goosefoot localities are roughly grouped within polygons to correspond to the various sand hill locations described in the report for Albertaand Saskatchewan. The polygons do not represent the actual boundaries nor full extent of the various sand hills.

Figure 4.  Smooth goosefoot localities are roughly grouped within polygons to correspond to the various sand hill locations described in the report for Albertaand Saskatchewan.

Chenopodium subglabrumis known from two localities in southwestern Manitoba: the Oak Lake area in the Routledge Sand Hills (White and Johnson 1980; Robson et al. 2005) and Spruce Woods Provincial Park in the Brandon (Carberry) Sand Hills (Figure 5).

During the summer of 2004 the Routledge Sand Hills site in Manitoba and six of the Saskatchewan populations were visited to determine if the species was still present, and if so, how many plants were present. Chenopodium subglabrum was found at each of the sites visited: Routledge, Seward (2 populations), Great (2 populations), Elbow and Dundurn Sand Hills. In 2004 staff from the Manitoba Conservation Data Centre visited the active sand dunes in the Brandon Sand Hills since the habitat was deemed appropriate for C. subglabrum, but no individuals were discovered. However, in 2005, staff from The Manitoba Museum found a small population of plants in Spruce Woods Provincial Park, a new Canadian locality.

Figure 5. Smooth goosefoot localities as found inManitoba. The open circle in the Routledge Sand Hills represents a historic population that was rediscovered in 2004; the solid black circle in the Carberry Sand Hills represents a small population confirmed in 2005. The polygons do not represent the actual boundaries nor full extent of the two sand hills.

Figure 5.  Smooth goosefoot localities as found inManitoba. The open circle in the Routledge Sand Hills represents a historic population that was rediscovered in 2004;

Although new populations of C. subglabrum were discovered in Saskatchewan (e.g. Seward and Great Sand Hills), four populations along the South Saskatchewan river (i.e. Birsay Sand Hills, Bridgeford, Broderick and Head of Qu’appelle) and one in a sandy area where stabilization has been extensive (i.e. McMahon) are likely no longer extant.

Page details

Date modified: