IOWA ACADEMY OF SCIENCES. 
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Quercus Mulilenbergii. Chestnut Oak. 
Not common. Found on steep, rocky hillsides. 
Quercus macrocarpa Michx. Bur Oak. 
Very common. Found everywhere, but more abun- 
dant on the upland. 
Quercus palustr is Du Roi. Spanish Oak. 
Frequent. 
Quercus rubra Linn. Red Oak. 
Common. 
Quercus coccinea Wang. Scarlet Oak. 
Quite common on upland. 
Quercus coccinea Yar. tinctoria Gray. Black Oak. Jack 
Oak. Common on upland. 
Salicacea:. 
Salix tristis. Dwarf Willow. Gray Willow. 
Somewhat rare. Found on upland bordering thickets. 
Salix humilis Marsh. Prairie Willow. 
Common on uplands. 
Salix discolor Muhl. Pussy Willow. 
Rare; wet places. 
Salix long if olia Muhl. Sand-bar Willow. 
Common in low, wet places and on sandbars. 
Salix nigra Marsh. Black Willow. 
Yery common along the banks of streams. 
Populus trem,uloides Michx. American Aspen. Quaking 
Asp. Rare. Upland. 
Populus monilifera Ait. Cottonwood. 
Yery common along streams, the largest trees grow- 
ing on very low ground near the water. This tree 
makes very rapid growth. Trees become large 
enough for lumber in thirty to forty years. 
Monocotyledones. 
Liliacea:. 
Smilax hispida Muhl. Greenbrier. 
Quite common in rich woods. 
