Relation of Weather to Crops 89 



especially in overfertilized or overirrigated soil. The blight attacks 

 new, fast-growing tissue, and works down into the tree, causing 

 cankers. No spray will check it. Every eflfort should be made to 

 induce a stocky, conservative growth. The pruning out of infected 

 parts below the infection is of very doubtful benefit, unless a section 

 is in a position to enforce a rigid inspection of every pear tree in 

 the agricultural district. There are few examples where this has 

 been done with success. 



There is only one pear in Arizona that will not blight. That is 

 the Prickly Pear. Kieffer and Garber are less susceptible than 

 varieties of French origin, but the quality of these Chinese pears is 

 so poor that they are not grown unless the blight is very bad. The 

 Bartlett is the most popular commercial variety. Other good 

 varieties are jNIadeleine, Clapp's Favorite, I^e Conte, Winter Nelis, 

 and Patrick Barry. 



PEAS 



Peas are produced in abundance in the gardens of Arizona 

 during the cool part of the year. They will stand temperatures of 

 22° to 25"^ without serious injury if they are not growing very 

 rapidly. Heavy frost will kill the blossoms of most varieties. In 

 the Yuma Valley it is warm enough for peas to bear most of the 

 winter, but in most parts of the State they can be grown either as 

 a fall or as a spring crop. Some of the hardier smooth peas may be 

 carried over winter without being damaged. 



The best time to grow peas in any part of the vState is as a very 

 early spring crop, planting being done between January 1 (or earlier) 

 and April 15, according to locality. 



Deep planting, 3 to 5 inches, is advisable, especially in the early 

 fall, when peas rot badly if near the surface. Planting of dwarf 

 varieties in double rows 10 to 12 inches apart, or in broad rows of 

 8 to 10 inches, allows the vines to support themselves, making 

 cultivation and picking easier. The standard varieties are little 

 grown because of the trouble and expense of supporting the vines. 



PECANS 



A few pecan trees are being cultivated in the Verde, Salt River, 

 and Lower Colorado valleys. They thrive best in deep, rich soils 

 with an abundance of irrigation. With proper culture they should 

 grow successfully at altitudes of 5000 to GOOO feet. They seem to 



