Manitoba’s Species At Risk

Threatened Western silvery aster Aster sericeus

estern silvery aster (Aster sericeus) is a also reproduce vegetatively, through the Wprovincially and nationally Threatened horizontal growth of . The buds wildflower, occurring in Manitoba, Ontario from which next year’s shoots will arise are Any native Manitoba species and 21 American states. It is a distinctive, formed underground by mid-September. likely to become endangered or late-summer herbaceous perennial, growing at risk due to low or declining to a height of 30 to 70 cm (12 to 28 inches). Distribution numbers in Manitoba if the Western silvery aster is found in central are characterized by several sparsely factors affecting it don’t North America, from Manitoba south to branched, brittle stems arising from a swollen improve. Threatened species . In Canada, Western silvery aster is are declared as such by woody rootstock. The lance-shaped are found only in southeastern Manitoba regulation under the densely covered with silky hair, giving them and in the Rainy River area of northwestern Endangered Species Act. a silvery appearance. Most lower leaves die Ontario. Most of Manitoba’s Western silvery and fall off by the time flowering occurs. aster plants are found in three areas: Birds Flowers are arranged in composite, or daisy- Hill Provincial Park and vicinity, Carlowrie like, flowering heads roughly 2.5 cm (1 inch) and between Gardenton and the Manitoba- across, with violet to pink ray flowers Minnesota border. Additional plants can be surrounding the central, yellowy-brown to found near Beausejour, Grunthal and Zhoda. rose disc flowers. Status Habitat The Manitoba Conservation Data Centre Western silvery aster can be found in considers the Western silvery aster to be dry , fields and openings in bur provincially rare (S2). While also considered oak/trembling aspen woodlands. Sites are very rare in Ontario and in many American usually south or west-facing, and their soils states, NatureServe considers the species are often coarse-textured (gravelly and/or to be secure (G5) overall. Western silvery sandy), calcareous (calcium-rich, or alkaline) and well to moderately-well drained. Western aster populations are threatened by gravel silvery aster is most abundant when growing extraction, the encroachment of woody in relatively undisturbed grasslands, but species into openings, invasion by plants can be found in disturbed sites such as non-native plants and pasture enhancement. roadside ditches and adjacent to gravel pits. Urbanization and gravel extraction have resulted in the apparent destruction of some Life History populations. Right-of-way maintenance activities can negatively affect roadside Western silvery aster is a perennial, populations. The haying of grasslands in late surviving from one year to the next as an summer can impact the species if flowering underground woody rootstock. Flowers appear from early August to mid-September, heads are removed before seed set. Insect and are pollinated by bees and other insects. predation and drought can also negatively Seeds are mature three to four weeks after affect reproduction. pollination, and are spread by wind. Plants Manitoba’s Species At Risk Cool Facts Get involved in recovery If you have Western silvery aster on your In some references, the scientific property, congratulations! Your land man- name of this species has been agement skills have helped maintain an changed from Aster sericeus to important part of Manitoba’s native flora. Please contact Manitoba Conservation at one of sericeum. The two the numbers below if you would like more names do represent the same . information on what you can do to further enhance your land for this and other native ● Manitoba plant and animal species. Surveys of Western silvery aster in Manitoba Conservation Canada have found about 6,500 Wildlife and Ecosystem Protection Branch stems. Birds Hill Provincial Park Box 24, 200 Saulteaux Crescent contains Canada’s largest Winnipeg MB R3J 3W3 (204) 945-7775 populations of Western silvery aster, www.gov.mb.ca/natres/wildlife/index.htm with about 4,200 stems. Manitoba Conservation Regional Offices ● Western silvery aster was listed as Threatened Eastern Region Predation and mining of seed in 1998 by regulation under Manitoba’s Lac du Bonnet heads by beetles and other insects Endangered Species Act. It has also been assigned (204) 345-1427 was found to reduce seed viability a status of Threatened by the Committee on Interlake Region in approximately 16 per cent of the Status of Endangered Wildlife in Canada Gimli seed heads collected from Birds (COSEWIC). A number of American states (204) 642-6077 also list Western silvery aster under their Hill and Carlowrie. Endangered Species Acts. Red River Region ● Winnipeg Stewardship and recovery (204) 948-3262 The swollen woody rootstock of A key component of recovery efforts is the • Western silvery aster is thought to protection of critical habitat. Remnant dry Partners in production of this fact sheet: have evolved as an adaptation tall grass prairie containing relatively large Manitoba Conservation, allowing plants to survive grassland populations of Western silvery aster are found Wildlife and Ecosystem Protection Branch Environment Canada, Canadian Wildlife Service wildfires and drought. at Birds Hill Provincial Park. Most other Manitoba Habitat Heritage Corporation populations, however, lie on private land or on road and railway right-of-ways. Land management techniques promoting the maintenance of native prairie at these sites will help to ensure the survival of Western silvery aster populations.

Monitoring of Manitoba’s Western silvery aster populations occurs on a regular basis. A number of new sites have been documented in the last several years.

Extirpated Species Endangered Species Threatened Species Vulnerable Species Any species once native to Any native Manitoba species Any native Manitoba species likely Species not regulated under Manitoba that has disappeared threatened to disappear through to become endangered or at risk the Endangered Species Act through all of its Manitoba range. all or most of its Manitoba range. due to low or declining numbers in but which could eventually Extirpated species are declared as Endangered species are declared Manitoba if the factors affecting it be considered Endangered such by regulation under the as such by regulation under the don’t improve. Threatened species or Threatened if the factors Endangered Species Act. Endangered Species Act. are declared as such by regulation affecting them do not under the Endangered Species Act. improve.