EXPERIMENT STATION BULLETINS. 301 



When the disease attacks young pear seedlings in the nursery, it is also 

 very troublesome, as it stops their growth and renders budding uncertain. 



It has been found that leaf blight can be readily held in check by the 

 use of the copper compounds, and that if the trees are sprayed with Bor- 

 deaux mixture at intervals of about two weeks, up to the middle of August, 

 there will be little if any injury from it. 



PEAR SCAB. 



The leaves and the fruit of the pear are sometimes attacked by this dis- 

 ease, which is considered identical with that of the apple (Fusicladium 

 dendrUicum). The principal damage is upon the fruit, and in some cases 

 it is quite severe, but the applications of the fungicides have been found to 

 give fruit nearly or quite free from it. 



INSECTS OF THE PEAR. 

 PEAB TREE SLUG {Eriocampa cerasi, 'Peck). 



This is the most common and the 

 worst insect enemy of the pear tree. 

 It is quite as common on the cherry 

 and is often found on quince, plum, 

 and similar trees. The parent fly of 

 the slug is jet black and when seen 

 on a leaf might be taken for a house 



Fig. 21.-Pear Tree sing, varions sizes. ^^ except that it is Smaller. It is 



called a saw fly as the female has a saw at the tip of the abdomen that she 

 uses to puncture the leaf in which to lay an egg. The 

 eggs soon hatch into slimy slugs that eat the tender por- 

 tion of the leaves and cause them later to appear dead. 

 There are two broods, the first one coming early in June 

 and the second late in July or August. The first brood is 

 Fig 22.-SawFiy. ^j^g ^^q ^\^^^ ^qq^ ^]^q harm, as the tree needs all its leafy 



growth in the early part of the season. 



Remedies. — Spray with the arsenites or hellebore, or dust the trees with 

 air-slaked lime, plaster, road dust, or ashes. The slugs are very easily 

 killed by any of these and if the first brood is destroyed there is 7io danger 

 of the second. 



Many of the insects that attack the apple, plum, and cherry, also work 

 more or less on the pear, such as the oyster-shell bark-louse, the borers, 

 codlin moth, plum curculio, and many of the caterpillars. 



THE SAN JOSE SCALE (Aspidiotus perniciosus, Comstock). 



Ten years ago this pernicious scale was not known east of the Rocky 

 mountains. Since that time colonies have been found in Virginia, Florida, 

 Maryland, New Jersey, Pennsylvania, New York, Canada, Ohio, and Mis- 

 souri, and no doubt, as the scale becomes better known, colonies will be 

 found in many other localities. Quite likely Michigan may meet with like 

 results, though we know of no colony at present within our borders. We 

 speak of the scale at this time, and furnish illustrations from the Depart- 



