16 
Willow— Leaves narrow, except in Bay-leaved Willow. Flow¬ 
ers in catkins. Stamens 2 to 8. Bracts not fringed. 
Fruit a small elongated dry pod. Seeds small, with long 
hairs. Many hybrids. Only the Black Willow is native. 
00 Length of blade not more than 3 times the width. Teeth 
blunt and glandular, 15 to 20 per inch of margin. Leaf¬ 
stalk with glands above. Stamens 3 to 5 or more—Bay- 
leaved Willow, Saliz pentandra L. 
00 Length of blade at least 4 times the width—01 
01 
01 
02 
02 
Stipules usually persistent. No glands on the leaf-stalk. 
Teeth 15 to 30 per inch of margin. Stamens 3 to 5 or 
more—Black Willow, Swamp Willow, Saliz nigra Marsh. 
Stipules usually not persistent. Leaf-stalk generally with 
glands. Stamens 2—02 
Marginal teeth of leaves averaging 10 to 15 per inch—03 
Marginal teeth of leaves averaging 15 to 30 per inch, blunt 
03 Length of leaf blade about 4 times the width. Marginal 
teeth blunt. Very variable—Crack Willow, Saliz fra gilts 
L. 
03 Length of leaf blade about 8 times the width. Lower sur¬ 
face pale. Marginal teeth sharp. Branches pendulous— 
Weeping Willow, Napoleon's Willow, Saliz babylonica L. 
04 Mature leaves silky hairy on both surfaces. Twigs greenish 
—White Willow, Saliz alba L. 
04 Mature leaves smooth. Twigs yellow or reddish—Yellow 
Willow, Saliz alba var. vitellina (L.) Koch. 
04 Mature leaves smooth and bluish green. Twigs olive- 
green — Blue Willow, Saliz alba var. cacndea (Sm.) Koch. 
Poplar —Leaves wide. Flowers in catkins. Stamens 8 or more. 
Bracts fringed. Fruit as in Willow. 
05 Leaf margins irregularly lobed or toothed. Lower surface 
white-cottony even when old. Cult, and escaped. Very 
variable—White Poplar, Abele, Silver Poplar, Populm 
alba L. 
05 Leaf margins regularly toothed, or but slightly irregu¬ 
lar—00 
* 
