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ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 51 



Fig. 101. — London 

 plane tree, with its 

 large maple-like leaves 

 (inset), is difficult to 

 distinguish from the 

 American sycamore. 

 However, the bark of 

 London plane tree is us- 

 ually more greenish in 

 color. 



four balls per stem on oriental plane tree, and one ball per stem 

 on sycamore. These balls, conspicuous on the trees during the 

 winter months, break apart in early spring, releasing the small 

 seeds which are scattered by the wind. The trunk bark is con- 

 spicuous because of its habit of peeling off in large patches annu- 

 ally. It is greenish white to creamy white on sycamore and dull 

 grayish to greenish white on London and oriental plane trees. 

 The bark on large branches and the trunks of young trees is very 

 smooth and greenish gray. The thick, dark brown bark on the 

 trunk bases of old trees is divided by deep furrows. 



The hard, heavy wood of sycamore, with its abundant cross 

 grains, is difficult to split and tends to twist and warp during 

 seasoning. It is used extensively for furniture, interior finishing, 

 veneer, tool handles, butcher's blocks, and boxes. 



Sycamore is susceptible to a fungus disease called leaf blight 

 or anthracnose. During cool springs this disease may cause 

 abundant killing and defoliation of young leaves, similar to the 

 injury resulting from severe frosts. Twigs and branches may 

 also be killed by the anthracnose fungus. This disease can be 



