12 — BULLETIN 24, U. S. DEPARTMENT OF AGRICULTURE. 
SILVICAL CHARACTERISTICS. 
DEMANDS UPON SOIL AND MOISTURE. 
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Cottonwood requires abundant soil moisture. It isnot adapted 
to dry situations, such as ordinary upland sites with thin soil. It 
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Fic, 1.—Catkins, twigs, and leaf and flower buds of cottonwood. a, Pistillate catkin; 6, 
enlarged scale of staminate catkin; c, staminate catkins; d, twig with leaf-buds; e, 
twig with flower-buds; f, twig, showing angularity ; g, longitudinal section of leaf-bud ; 
h, longitudinal section of flower-bud. 
seldom establishes itself naturally where surface moisture is lacking, 
although, if planted on such sites, it frequently makes very satis- 
