380 Report of the Horticulturist of the 



young stock, beginning about tlie first of June and repeating tlie 

 application at intervals of from ten to fourteen days. Directions 

 for making Bordeaux mixture are given in article 4 on Fungi- 

 cides and Insecticides. 



The Cherry Aphis. — This little insect is one species of a large 

 family, commonly known as plant lice. They are similar in size and 

 form to connnon green plant lice, but are nearly black in color. 

 They appear early in the spring and begin sucking the juices from 

 the expanding buds. They multiply very rapidly and as growth 

 takes place move to the new shoots and leaves, where they collect in 

 large numbers, esjjecially on the under side of the leaves, causing 

 them to curl up so as to cover the lice and thus making it difficult to 

 hit them with a spray after they have become well established. 

 Since these insects suck their food they cannot be poisoned but 

 must be killed by contact of the insecticide with their bodies. 



Remedy. — In fighting these insects close watch should be kept 

 for their first appearance, so that they may be sprayed at once and 

 not allowed to become established. The treatment should be re- 

 peated as circumstances require. Kerosene emulsion diluted from 

 twelve to fifteen times is commonly recommended for plant lice. If 

 the leaves are cu:led so that the spray cannot reach the insects, dip 

 the infested twigs in whale oil soap and tobacco tea, or in kerosene 

 emulsion prepared as directed in article 4 on Fungicides and In 

 secticides. The mixture is poured into shallow pans and the twigs 

 are bent over and dipped into it. 



Pear. 



Leaf Blight. — The leaf blight that has been described as attack- 

 ing the pear and quince in the orchard, often does great damage to 

 nursery stock. Tlie following account is based on investigations 

 made at this Station. i^ For some as yet unexplained reason the 

 blight is more severe on seedlings than on budded or grafted stock. 

 The disease attacks the leaves and causes many of them to 

 drop off, and in some cases the tender part of the stock is killed 

 back several inches. As soon as the leaves fall, new ones are at 

 once pushed out. This process is yox^ exhausting and where the 

 attack begins early in the season, the seedlings may lose 

 several sets of leaves during the summer. Where this occurs 



15 Annual Report of this Station, 1892; 652 



