Sweet Potato^ Sycamore. 369 



considerable damage. The larvae appear during the summer, 

 and feed upon the foliage. 



Treatment. The same treatment recommended for the de- 

 struction of the currant sawfly will also destroy these insects. 

 The applications, however, need not begin until the young 

 larvae are noticed, but they should be repeated as required 

 during the summer. 



Tortoise Beetles; Golden Bugs (Cassidce). Description. The 

 insects hibernate in the adult state. They attack the young 

 potato vines during May and June, eating irregular holes in 

 the foliage. Eggs are laid, and during June and July the 

 larvae appear. At this time the vines are growing so fast that 

 the insects do comparatively little injury. The adults appear 

 again during July and August, but no eggs seem to be laid 

 until the following spring. 



Treatment. Professor J. B. Smith recommends the use of 

 Paris green or London purple at the rate of 1 pound to 175 

 gallons of water. The application should be made as soon as 

 injury is noticed, both sides of the leaves receiving treatment. 

 The vines should be treated again if the first application does 

 not prove effective. 



SYCAMORE. 



Leaf Blight (Glceosporium neruisequum, Sacc.). Description. 

 Both the native and the foreign species of plane trees are sub- 

 ject to the attacks of a fungus which causes the leaves to appear 

 as if scorched. The disease develops so early in the season 

 that the injury caused by it is often ascribed to frost. Entire 

 trees are frequently discolored by the abundance of brown leaf 

 surface, and although this form of the disease is present only 

 about two months, still trees have been killed by the repeated 

 attacks of the fungus. Diseased leaves often fall. 



Treatment. The severity of the attacks can undoubtedly be 

 diminished by spraying with fungicides as soon as the leaves 

 unfold in spring, repeating the operation so that all new growths 

 may be protected. But such applications can only be made to 

 smaller trees, and when they are impracticable a probable help 

 in checking the malady is to burn all affected leaves that fall 

 from the trees. 



2B 



