Trimorpha acris (L.) Nesom var. kamtschatica (DC.) Nesom
Habitat: Damp, sandy banks, thickets, and clearings.
Range: Circumboreal; south to Maine, Michigan; west to Utah.
Aids to Identification: Bitter fleabane is a stout, erect biennial or short-lived perennial herb (3-8 dm tall). It has a 5-12 mm tall involucre; peduncles with glandular hairs; capitula with a series of rayless, carpellate flowers within the series of ray flowers. The rays become filiform and inconspicuous in drying. The leaves are mostly oblanceolate growing up to 10 x 1.5 cm.
Ecological characteristics: Although it can apparently grow in shade, in dry or rocky woods, this species seems to grow most vigorously in rich, moist soil where it receives at least partial sunlight. Usually fruits abundantly.
Phenology: Flowers July and August.
Family: Asteraceae. The other rare fleabane in Maine is Erigeron hyssopifolius.
Synonyms: Some newer treatments refer to this species as Erigeron acris L. ssp. kamtschaticus (DC.) Hara. Other synonyms include E. acris L. var. kamtschaticus (DC.) Herder; E. angulosus Gaudin var. kamtschaticus (DC.) Hara; E. kamtschaticus DC.
Reason(s) for rarity: At southern limit of range.
Conservation considerations: None noted.