Very local. In addition to my specimens it has been reported from Lake, Montgomery, Porter, and St. Joseph Counties. One of my specimens is from a small colony at the base of a north beech slope, bordering a soft maple swamp, and the other is also from a swamp bordering a lake. My specimens are not typical and seem to be intermediate between the species and the var. dendroideun (Michx.) D. C. Eaton.
Prostrate stems deeply subterranean, elongate, branched; erect stems scattered, simple below, freely branched above, to 3 dm, the main axis 2 mm thick, the branchlets terete or flattened; lvs numerous, shining, 6-8-ranked, linear-subulate, all alike or ±dimorphic, 4.6 נ0.8-1.2 mm, entire, firm, sharp-pointed; cones terminating some of the branches; sessile, 1-4 cm, 5-7 mm thick; sporophylls yellowish, broad-based, abruptly acuminate, with hyaline, inconspicuously erose margins; sporangia reniform, 1.5-2 mm wide; spores with the commissural faces more finely reticulate than the outer, otherwise as in no. 9 [Lycopodium annotinum L.]; 2n=68. Moist woods and bog-margins in acid soil; boreal Amer. and Asia, s. in e. U.S. to n. Ga., Ala., Ind., and Mo.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.