Coefficient of Conservatism:
Coefficient of Wetness:
A. A. Reznicek
Sphagnum "lawns" in bogs, especially near water, fens, rock pools (Isle Royale), marly shores.
This circumpolar species is a tetraploid derived from hybridization of the northern North American Drosera linearis with the very widespread D. rotundifolia and doubling of the chromosome number. In Michigan, this is widespread, but local in the Upper Peninsula, especially near Lake Superior, with records from Chippewa Co., Keweenaw Co. (including Isle Royale), Luce Co., Marquette Co., and Schoolcraft Co.
The F1 hybrid, however, which bears the name Drosera ×woodii R. Gauthier & Gervais, also occurs in Michigan, and may be expected in fens and Interdunal calcareous flats, wherever the parents grow near each other. Both the F1 hybrid and the tetraploid species derived from it are pooled on the distribution map. Drosera linearis, however, ranges farther south in Michigan than D. anglica and, so far as known, all "anglica" plants mapped from the Lower Peninsula are Drosera ×woodii, as is at least one collection from Luce Co.
These F1 hybrids are sterile, the pollen malformed and ovules and seeds aborting with no ripe fruit developing. Like the parents (and D. intermedia) they are diploid (2n = 20). Otherwise, they may be morphologically similar to the fertile tetraploid. There is a tendency for D. anglica to have proportionately more narrowly spathulate leaves held more upright than the F1 hybrid, though this is a subtle difference. Naturally, the sterile hybrid can be strongly suspected when solitary or few scattered plants are seen intermingled with D. linearis and D. rotundifolia, rather than forming substantial populations.