Loomis' Yellow Loosestrife

Description

Stems erect, much-branched, 3-7 dm, glabrous or sparsely stipitate-glandular, especially distally; rhizomes slender; bulblets absent. Leaves usually opposite (to subopposite or whorled); petiole absent; blade linear to narrowly elliptic, 2-6 - 0.1-0.8 cm, base truncate or cuneate, slightly decurrent, margins entire, revolute, eciliolate, apex acute to obtuse, surfaces punctate, glabrous; venation single-veined. Inflorescences terminal, racemes, 3-10 cm. Pedicels 0.7-1.1 cm, glabrous to sparsely stipitate-glandular. Flowers: sepals 5, calyx streaked with black resin canals, 3-6 mm, slightly stipitate-glandular at least marginally, lobes lanceolate, margins thin; petals 5, corolla yellow with reddish base, streaked with black or reddish-black resin canals, rotate, 4-7 mm, lobes with margins entire, apex rounded, stipitate-glandular adaxially; filaments connate 0.4-1 mm, shorter than corolla; staminodes absent. Capsules 3-3.5 mm, not punctate, glabrous. 2n = 42.