[Salix humilis var. microphylla (Andersson) Fernald, moreSalix longirostris Michx., Salix muehlenbergiana Barratt ex Torr., Salix occidentalis Bosc ex K. Koch, Salix recurvata Schleich., Salix tristis Hort. ex Pursh, Salix tristis var. longifolia Andersson, Salix tristis var. microphylla Andersson, Salix tristis var. momadelphia Barratt]
Low to mid shrubs, 0.3-1 m. Stems decumbent; branches tomentose, peeled wood smooth or striate, striae sparse, to 2 mm; branchlets yellow-brown. Leaves: stipules absent or rudimentary on late ones; petiole 0.5-3(-6) mm, velvety or villous adaxially; largest medial blade narrowly oblong, narrowly elliptic, oblanceolate, or obovate, (13-)20-50(-70) × 3-13 mm, 2.3-9 times as long as wide, margins strongly revolute, abaxial surface hairs gray throughout, adaxial slightly glossy, moderately densely tomentose; proximal blade margins entire. Catkins: staminate 6.5-13.5 × 5-10 mm, flowering branchlet 0-1 mm; pistillate 11-17.5 × 5.5-12 mm, flowering branchlet 0-1.5 mm; floral bract 0.8-1.4 mm. Staminate flowers: filaments glabrous or hairy basally. Pistillate flowers: ovary pyriform; ovules 6 per ovary; stigmas 0.2-0.24-0.32 mm. Capsules 5-9 mm. Flowering early Mar-late May. Moist limestone and serpentine barrens, open heath balds, open pine woods, moist prairies, swampy areas in open deciduous woods, stream banks; 60-1600 m; Ark., Conn., Del., D.C., Ga., Ill., Ind., Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Pa., R.I., S.C., Tenn., Va., W.Va., Wis. Hybrids:
Although variety tristis is reported to hybridize with Salix eriocephala, S. humilis var. humilis, and S. petiolaris (G. W. Argus 1986), hybrids have not been confirmed.
Shrub 0.5 - 1 m tall Leaves: alternate, on yellowish to pinkish, 2 - 3 mm long, hairy leafstalks, dark green above, paler with a waxy coating (glaucous) beneath, yellowish to pinkish on midrib, 2 - 5 cm long, 0.5 - 1 cm wide, narrowly lance-shaped to linear-oblong with a tapering base and pointed tip, slightly revolute (rolled downward along the margins), sometimes hairy above, and gray-woolly beneath. Young leaves are brownish red, thin, translucent, and minutely hairy. Flowers: either male or female, borne on separate trees (dioecious) in stalkless, oval to egg-shaped, hairy catkins. Female catkin green to purplish with blackish scales, 1 - 2 cm long. Stigmas red. Ovary densely hairy. Male catkin whitish with blackish scales, 0.5 - 1.2 cm long. Stamens two, with red anthers (turning yellow). Fruit: a capsule, in elongated clusters, short-stalked, brownish, flask-shaped, and hairy. Seeds have long, white, silky hairs attached. Twigs: slender, brown-tinged, and hairy. Buds: reddish brown to brown, egg-shaped, flattened, pointed, and slightly hairy.
Similar species: In the Chicago Region, Salix humilis var. tristis differs from most other willows by having hairy leaf undersides and downward-rolled (revolute) leaf margins that are not distinctly toothed. Variety humilis is similar to variety tristis but on a larger scale, with leaves that do not remain hairy. Salix pedicellaris, a small shrub that grows in bogs and fens, has leaves similar to both S. humilis varieties; however, the leaves of S. pedicellaris are finely net-veined on both sides and have parallel primary lateral veins.
Flowering: April to early May, before the leaves
Habitat and ecology: Occasionally found in the Chicago Region, in prairies and other dry open places.
Occurence in the Chicago region: native
Notes: Planted as an ornamental.
Etymology: Salix is the Latin word for willow. Humilis means low-growing. Tristis means dull.