42 SALICACEAE 



The variety W heeler i (Rowlee) Schneider is distinguished 

 chiefly by its leaves, which are shorter and broader, i.e., 2 to 4 

 inches long by about ^ to ^ inch wide, and also densely cov- 

 ered by long and rather permanent hairs. It is in this last 

 respect said to resemble the S. argophylla of the Pacific Coast. 

 In Illinois, it appears to be rare and is definitely recorded only 

 in St. Clair, Winnebago and Cook counties. 



SALIX CORDATA Muhlenberg 

 Heartleaf Willow Cordate Willow 



The Heartleaf Willow, fig. 5, is a shrub of rather large size, 

 generally 5 to 25 feet high, with a bushy habit and moderate to 

 rather slender twigs that bear long, narrow, dark green leaves. 

 The leaves are narrowly to broadly oblanceolate or lanceolate, 

 acuminate at the tip, generally cordate but often rounded to the 

 petiole at the base, dark green above and glaucous-white or at 

 least lighter green beneath. They are closely and finely serrate 

 but not revolute on the margins, often puberulent upon emer- 

 gence but later glabrous*, and 3 to 5 inches long by yi to U/z 

 inches wide. In age they become rigid, with strong, conspicuous, 

 white or yellowish to light brown petioles at first more or less 

 pubescent but later glabrous and about ]/i to Yz inch long. They 

 are subtended by semicordate to rotund, sharply serrate, gla- 

 brous, persistent stipules up to Yz inch long. The yellowish to 

 dark brown twigs are terete, often lined or ridged below the 

 leaf-scars; they are pubescent at first and often, the floral 

 twigs especially, remain so throughout their first year, other- 

 wise becoming glabrous. The appressed buds are dark yellow to 

 dark brown, conical, pointed and pubescent, and measure about 

 1/^ to 14 inch long. 



The catkins, which appear simultaneously with the leaves, 

 are nearly sessile. They are 1 to 2^ inches long and quite 

 slender, being only about Y ^^^^ wide. Pistillate catkins become 

 2 to 3 inches long at maturity. Staminate flowers have 2 sta- 

 mens, the filaments of which are glabrous. The styles of pistil- 

 late flowers are short and undivided and bear 2 entire or divided 

 stigmas half as long as the style. Mature capsules are lanceo- 

 late, about Y iiich long, glabrous, greenish to tan brown, and 

 provided with. a short pedicel about equal in length to the scale, 

 which is oblong, lanceolate, brown, and more or less hairy. 



