UNITED STATES DEPARTMENT OF AGRICULTURE 



1 BULLETIN No. 316 4 



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Contribution from the Forest Service 

 HENRY S. GRAVES, Forester 



S^-'^J-U 



Washington, D. C. 



PROFESSIONAL PAPER 



December 20, 1915 



WILLOWS: THEIR GROWTH, USE, AND 

 IMPORTANCE. 



By George N. Lamb, Forest Examiner. 



CONTENTS. 



Introduction 1 



The tree and its forms 2 



Soil, moisture, and light 7 



Susceptibility to injury 7 



Life history of the black willow 9 



Characteristics of willow wood 26 



Uses of willow wood. 27 



Use of willow trees for protection 37 



Planting willows 43 



Cultivation and care 48 



Cutting 48 



Cost of growing willows 49 



Yield from willow plantations 50 



INTRODUCTION. 



There are in the United States and Canada from 80 to 100 species 

 of willows, distributed from the Gulf of Mexico to the Arctic Circle, 

 and from tidewater to the tops of the highest mountains. They 

 range from a tiny plant a few inches high to forest trees 4 feet in 

 diameter and 140 feet in height. All the shrubbery species are useful 

 as soil cover, forage, or basket material. Scarcely more than a 

 dozen, however, are of prime economic importance. Of these, six are 

 species imported from Europe: The basket willows, which are the 

 American green willow (Salix amygddlina) , the Lemley willow (Salix 

 pentandra), and the purple willow (Salix purpurea), and three tree 

 willows, the white willow (Salix alba), the crack willow (Salix fragilis), 

 and the weeping willow (Salix bahjlonica). There is only one native 

 tree species of wide distribution and importance, and this, the black 

 willow (Salix nigra), is found from coast to coast and from the Lakes 

 to the Gulf. It reaches tree size over most of this range, attaining 

 its maximum development in the lower Mississippi bottom lands. 

 The other native species of economic importance are Salix amyg- 

 daloides, Salix cordata, and Salix Jluviatalis, which are primarily 

 eastern >ui<l central .pecies, and Salix lasiairdra , Salix laevigata, Salix 

 Vjy.ioh pin, niid S'llix JindlenaiHi, the western tree willows. 

 BOO*— Bull. 310—15 1 



