Till-: Control of Insect Pests and Plant Diseases. 6ci 



trees in three forms, blossom blight, twig blight, and blight cankers on limbs and 

 body. It is caused by bacteria which are distributed by bees and flies and is not 

 controlled by spraying. Cutting out and destroying the diseased parts are the 

 chief measures to be taken. Make a systematic inspection of the trees one to 

 three times a week during the growing season, cutting out all blighted twigs and 

 disinfecting the cuts as described below. The bacteria of this disease are carried 

 over winter in cankers on the main limbs and bodies of the trees. Remove all 

 such cankers with a sharp knife, cutting well into the healthy bark, and wash the 

 wound with corrosive sublimate, i part to looo 

 of water. Then paint the wound with gas tar or 

 lead paint. (Cornell Bulletin 272.) Destroy or 

 clean up all old pear and apple trees about the 

 premises because such trees harbor the disease. 



This important fungous disease 



New York should not be confused with 



apple-tree the "blight canker." Cankers 



canker. are usually found on the main 



Fig. 210. limbs of old trees, black and 



rough. This canker is very 



common on Twenty Ounce. Since the fungus 



enters through wounds, avoid breaking the bark. 



All wounds made in pruning should be promptly 



painted over. Cut out cankers and treat as for YiG. 208. Apple-scab 



"blight canker." Spray early in spring before 



the buds start with lime-sulfur 1-12 or Bordeaux 10-10-50; soak the body and 

 the limbs when making first application for scab. Geneva Bulletins 163 and 185. 



ASPARAGUS. 



The most common and destructive disease of asparagus. It 

 Rust. produces reddish or black pustules on the stems and branches. 



Late in the fall, bum all affected plants. Fertilize liberally and 

 cultivate thoroughly. During the cutting season, permit no plants to mature and 

 cut all wild asparagus plants in vicinity once a week. Rust may be partially con- 

 trolled by spraying with Bordeaux, 5-5-50, containing a sticker of resin-sal soda 

 soap (see page 502), but it is a difficult and expensive operation and probably not 

 profitable except on large acreage. Begin spraying after cutting as soon as new 

 shoots are 8 to 10 inches high and repeat once or twice a week until about Septem- 

 ber 15. (Geneva Bulletin 188.) Dusting with sulfur has proved effective in 

 California. (California Bulletins 165 and 172.) Plant the varieties least affected 

 by rust. 



BEANS. 



A fungous disease commonly known among growers as "rust." 



Antnracnose j^. j^ carried over from one season to another in the seed. 



or poa-spoi. pjant clean seed obtained by selecting pods free from the dis- 



^^' ^^^' eased spots. Hand-sorting of seed and seed treatment will not 



control this disease. When beans can be thoroughly hand-sprayed, Bordeaux, 



5-5-50, will control the trouble. Spray, first, ju.st when the plants break 



through the ground; second, when first pair of leaves are expanded; third, when 



the pods have set. Cornell Bulletin 339 and New Jersey Bulletin 151. 



