Plants and Animals
Juncus dichotomus Forked rush
Perennial rush of wetlands, less than 40 cm tall with ridged stem; leaves basal, mostly involute (i.e., rolled-in) without hard cross-partitions; auricle margin thin, translucent, less than 0.6 mm long. inflorescence terminal; flowers attached singly. Auricle characteristics are critical to differentiate from the similar path rush (J. tenuis) and Dudley’s rush (J. dudleyi) which differ in combinations of auricle thickness and length.
Status and Rank
US Status: No Status/Not Listed
State Status: SC - Special Concern (rare or uncertain; not legally protected)
Global Rank: G5 - Secure
State Rank: SNR - Not ranked
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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.
Primarily occurs along the Atlantic coastal plain in the southeastern United States but this species has a discontinuous distribution in the southwestern Lower Peninsula of Michigan. Usually found in sandy, acidic, well-drained but wet soils, like sandy meadows and shores. Has been found in brackish areas in other parts of its range.
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.
Colic root (Aletris farinose), common ragweed (Ambrosia artemisiifolia), big bluestem (Andropogon gerardii), blue-joint grass (Calamagrostis canadensis), three-ribbed spike-rush (Eleocharis tricostata), round-headed rush (Juncus scirpoides), marsh blazing star (Liatris spicata), switchgrass (Panicum virgatum), white oak (Quercus alba), black oak (Q. velutina), and prairie cordgrass (Spartina pectinata).
Possibly overlooked species that needs a status survey in southwestern Michigan. This species requires conservation of habitat and regional and local protection of the hydrology. When occurring in a marsh or depression within or surrounded by fire-dependent natural communities, prescribed burn management can stimulate seed germination and flowering, reduce woody encroachment to maintain open habitat, and maintain a diverse seed bank. This species is also vulnerable to off-road vehicle impacts and dredging and filling activities.
Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgment of the investigator.
Survey Period: From first week of July to first week of September
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