CHAPTER XXX 

 SYCAMORE OR PLANE-TREE DISEASES 



The species of sycamore or plane-tree are large trees growing 

 abundantly throughout their range in bottom-lands. Although 

 not making a part of the forest lands of the cotmtry, the wood of 

 sycamore is utilized for many specialized products. Three 

 species of Platanas are recognized as native to the United States. 

 Others are Mexican. A common street tree is P- acerifolia, 

 thought to be a hybrid and often passing as P. orientalis, 

 which latter is native in Europe and Asia. 



The sycamore is apparently subject to but few important 

 diseases. The leaf- and twig-blight, however, causes serious 

 damage to the tree wherever it grows. The trees are de- 

 formed and although defoliated frequently, are not often killed. 

 Several other fungi cause leaf-spots of sycamore. No other 

 diseases of importance have been recorded on this tree. This 

 may be due partially, however, to a lack of attention to the 

 tree, since it is not associated with the principal timber-trees 

 and is of little economic importance. 



Leaf- and Twig-Blight 



Caused by Gnomonia veneta (Saec. and Speg.) Klebahn 



, The most common and destructive disease of the sycamore 

 is the leaf- and twig-blight or anthracnose. Some species of 

 oak, especially those belonging to the white and red groups, 

 suiler to some extent from the same disease. The disease 

 is generally prevalent throughout eastern and central United 



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