18 A PLANT-DISEASE SURVEY IN TEXAS.. 



Table IV. — Average daily evaporation at San Antonio Experiment Farm. 





Month. 



Evapora- 

 tion. 



Average for— 



Month. 



Evapora- 

 tion. 



Average for — 



1909. 



January 



February 



March 



Inch. 

 0.103 

 .149 

 .188 

 .235 

 .237 

 .331 

 .357 

 .274 

 .241 



Entire month. 



Do. 



Do. 

 26 days, i 

 Entire month. 

 First 27 days. 

 Last 25 days. 

 First 30 days. 

 Entire month. 



1909. 



October 



November 



December 



1910. 



January 



February 



March 



Inch. 

 0. 182 

 .127 

 .092 



.090 

 .103 

 .191 



Entire month. 

 Do. 

 Do. 







May 





June 



First 24 days. 

 Last 26 days. 

 Entire month. 



July 



August 



September 







i No records for Apr. 17, 18, 19, 20. 

 CROPS AND NATIVE VEGETATION. 



The elimatological character of the San Antonio area excludes cer- 

 tain crops which are extensively grown in more northern localities 

 and in regions of greater rainfall, but makes possible the culture of 

 some crops which are characteristic of semitropic conditions. 



FRUITS. 



Apple orchards conducted on a commercial scale are excluded. In 

 a few localities small numbers of trees are to be found in family 

 orchards which generally appear to be seriously affected with black- 

 rot. In the sheltered valleys in the low mountain country to the 

 northwest the most favorable conditions for the growth of apples are 

 found. Several nurseries in the territory grow large quantities of 

 apple stock for shipment to old Mexico, Arizona, and the Pecos coun- 

 try in Texas. The young trees in the nursery were unusually exempt 

 from diseases. 



Pears are more successfully grown than apples, but commercial 

 orchards are rare. Most of the small pear orchards have been very 

 seriously neglected, and it is not surprising to find them affected with 

 such diseases as black-rot and bitter- rot. With proper care and culti- 

 vation pears could be more extensively grown, since they are much 

 freer from fire-blight than in the more humid coast country. 



Peaches are common in the eastern half of the territory and are 

 grown to some extent in the sheltered valleys to the west and north- 

 west. The crop for 1909, however, was a complete failure, owing to 

 the severe freezes of the previous winter. The sudden drops in tem- 

 perature following warm periods which had started vegetative ac- 

 tivity killed many peach trees. This condition will explain the 

 rarity of such diseases as brown-rot and peach freckle ( Cladosporium 

 carpophilum) , which are very abundant when there is an average 

 crop. The entire absence of the peach leaf-curl which is so common 

 farther north may be noted. Present records give only a single 



226 



