242 Minnesota Plant Life. 



serve to protect the flower-buds during the cold nights or oc- 

 casional freezing weather of early spring. 



As beach plants, the long-leafed willow, the hoary willow, 

 the heart-leafed willow, the shining-leafed willow and a few 

 others are common, especially along sand-bars, where there is 

 considerable spray from the surf. At Lake of the Woods some 

 very interesting willow-clothed beaches have been observed. 

 Different species of willows on such beaches often arrange them- 

 selves in zones, one variety nearer the water, and another far- 

 ther back. Some of the willows, notably the hoary willow and 

 the heart-leafed willow, along the shores of northern lakes, 

 grow 7 in a very regular more or less hemispherical fashion, re- 

 sembling the trimmed shrubs of some city park. 



The bark of the willow is bitter and is sometimes used as a 

 febrifuge in place of quinine, but it is not particularly efficacious. 



