Plants and Animals
Aristida dichotoma Three-awned grass
Small tufted annual grass (20-40 cm) of dry sandy soil; spikelets with three awns, the middle awn loosely spiraled at base, 4-8 mm; lemma 5-7 mm.
Status and Rank
US Status: No Status/Not Listed
State Status: X - Presumed extirpated (legally 'threatened' if rediscovered)
Global Rank: G5 - Secure
State Rank: SX - Presumed extirpated
|County||Number of Occurrences||Year Last Observed|
Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.
Known from a single collection in Kalamazoo County, where it was collected in 1935 from "sterile sandy soil". Elsewhere within its broad U.S. range, it occurs in dry, sandy soil.
Natural Community Types
For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.
Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.
No collection data are available from the Michigan collection; though this rare grass may have occurred with such dry-site species as poverty grass, little bluestem, old-field goldenrod, Pennsylvania sedge, ground juniper, shining sumac, wild plum, and New Jersey tea.
Requires early successional habitat and local disturbance. Fire may also be important in maintaining habitat.
Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgement of the investigator.
Survey Period: From fourth week of August to first week of October
- Elzinga, C.L., D.W. Salzer, and J.W. Willoughby. 1998. Measuring and Monitoring Plant Populations. The Nature Conservancy and Bureau of Land Management, Denver. BLM Technical Reference 1730-1. 477pp.
- Goff, G.F., G.A. Dawson, and J.J. Rochow. 1982. Site examination for Threatened and Endangered plant species. Environmental Management 6(4): 307-316
- Nelson, J.R. 1984. Rare Plant Field Survey Guidelines. In: J.P. Smith and R. York. Inventory of rare and endangered vascular plants of California. 3rd Ed. California Native Plant Society, Berkeley. 174pp.
- Nelson, J.R. 1986. Rare Plant Surveys: Techniques For Impact Assessment. Natural Areas Journal 5(3):18-30.
- Nelson, J.R. 1987. Rare Plant Surveys: Techniques for Impact Assessment. In: Conservation and management of rare and endangered plants. Ed. T.S. Elias. California Native Plant Society, Sacramento. 8pp.
- Braun, E. L. 1967. The Monocotyledoneae of Ohio. Cat-tails to Orchids. Ohio State University Press, Columbus. 464pp.
- Dore, W.G. and J. McNeill. 1980. Grasses of Ontario. Agriculture Canada Research Monographs 26: 566pp.
- Flora of North America Editorial Committee. 2003. Flora of North America, North of Mexico. Volume 25: Magnoliaphyta: Commelinidae (in part): Poaceae, part 2. Oxford University Press, New York. 783pp.
- Voss, E. G. 1972. Michigan Flora. Part I. Gymnosperms and Monocots. Bulletin of the Cranbrook Institute of Science and University of Michigan Herbarium. 488pp.