92 Bulletin 78 



The best variety at present grown is the Marsh or Marsh's 

 Seedless. It is probable that the poor quality of much of the western 

 fruit is due, in a large measure, to the necessity of growing varieties 

 poorly adapted to our conditions. Arantium, Duncan, and Triumph 

 are sometimes grown. 



POTATOES 



But a very small proportion of the Irish potatoes consumed in 

 Arizona is produced within the State. This is due to the fact 

 that except at a few specially favored localities in the mountains, 

 where irrigating water is available, potatoes are grown with con- 

 siderable difficulty. While not easily grown in the hot southern 

 valleys, they do moderately well when the methods that it is essen- 

 tial to follow for their successful culture are understood. Being 

 sensitive both to the frosts of winter and the heat of summer, they 

 can be grown only during late winter and early spring, and during 

 the fall. For the spring crop they are planted during the latter part 

 of January or the early part of February, and mature about the first 

 of June. For a fall crop they are planted during the latter part of 

 August or the first few days of September. The fall crop does not 

 always fully mature before the frosts of November, but usually 

 furnishes a limited supply of young potatoes for the table. The 

 following additional remarks apply especially to the Salt River 

 and Colorado River valleys. 



With the exception of possibly a month in summer and al)out 

 two months during winter, potatoes will germinate with more or 

 less promptness after being planted in fairly moist soil. The usual 

 planting season here is from the middle of January to the middle of 

 February. Tubers planted during January send up sprouts nearly 

 as rapidly as those planted later, but the young plants are apt to 

 be injured by frosts. Potatoes planted December 23, 1899, and 

 January 17, 1900, came up during February and were slightly 

 injured by frost that occurred February 24, when the mercury fell 

 to 26° at the ground, 29° in the government shelter, and 37° at the 

 Weather Bureau, no injurious frosts occurring during March of 

 that year. Potatoes planted January 9 and February 1, 1901, were 

 slightly injured March 13, when the minimum temperatures were 

 27 at the ground, 32° in the government shelter, and 37 at the 

 Weather Bureau. They continued growing until March 25, when 

 those planted in January had reached a height of six to eight inches 

 and those planted February 1, a height of two to four inches. Upon 



