There are currently no active references in this article.
A vigorous, richly leafy shrub or small tree, making long stiff shoots annually, and reaching 10 to 15 ft high; young shoots downy at first, getting glabrous by late summer. Leaves closely set on the branch, often furnished with a pair of large ear-shaped stipules, ovate-lanceolate, rounded or heart-shaped at the base, slender pointed, finely toothed, 3 to 6 in. long, 3⁄4 to 11⁄2 in. wide; green and glabrous on both sides except the midrib, which is slightly downy above; stalk 1⁄2 to 1 in. long. Catkins up to 2 in. long, produced on the naked wood in April, with one or a few tiny leaf-like bracts at the base of each. Stamens two. Ovaries long-stalked.
Native mainly of eastern and central N. America, but so closely related to the more western S. lutea and S. mackenzieana, into which it probably merges through intermediate forms, that its western limits are not clear. It was introduced to Britain in 1812. A very well-marked willow by reason of the large, long-stalked leaves usually cordate at the base, and the conspicuous persistent stipules. It varies in the shape and width of its leaves; in var. angustata (Pursh) Fern, they are around 5⁄8 in. wide and tapered at the base.
S. rigida is represented in cultivation by a female clone with brownish red young leaves. This was, in fact, the characteristic of the clone distributed by Dieck in the last century under the name “S. nicholsonii purpurascens”, but according to Fernald tinted young growths are a normal feature of this species.
S. missouriensis Bebb ?S. eriocephala Michx.; S. rigida var. vestita (Anderss.) C. K. Ball – Stems permanently downy or woolly. Leaves more tapered at the apex than in S. rigida, glaucous beneath. Stipules smaller. Central USA.
S. lutea Nutt. S. cordata var. watsonii Bebb; S. rigida var. watsonii (Bebb) Cronq.; S. cordata var. lutea (Nutt.) Bebb – Branchlets usually yellowish, they and the leaves quickly becoming glabrous. Leaves yellowish green above, glaucous beneath, narrowly to often broadly lanceolate, sometimes entire. Western N. America, as far west as W. Ontario, Montana, Nebraska and Colorado, south to California.
S. mackenzieana Barratt ex Anderss. S. cordata var. mackenzieana Hook.; S. rigida var. mackenzieana (Hook.) Cronq.; S. monochroma Ball – Branchlets usually brown as in S. rigida from which it differs in its glossier, lighter green, mostly lanceolate leaves almost glabrous from the start, less conspicuous stipules, sparsely hairy catkin-scales and longer-stalked capsules (up to 1⁄6 in. long). Like S. lutea a native of western N. America but with a more northern distribution. Described from specimens collected in N.W. Canada on the Mackenzie river and Great Slave Lake.
S. ‘Americana’. – A probable hybrid of S. rigida, cultivated on the continent as a basket willow. It was introduced from the USA to Germany in the last century by the basket-maker Ernst Hödt, and propagated by Otto Schön’s willow-nursery, which distributed three million cuttings in 1914 (S. americana Hort. ex Schwerin, not Anderss.). Rehder suggested that it is a hybrid of S. purpurea, a species long cultivated in the USA, with S. rigida as the probable second parent, but it is now considered to be S. rigida × S. gracilis. It is a male clone.