LETTUCE 



273 



Cultivation. Lettuce is the most universally cultivated salad 

 plant grown in the United States. It is undoubtedly the most val- 

 uable from a commercial standpoint and holds an important place in 



the market crops of 

 gardeners and truck 

 growers. This is a 

 result of the fact 

 that it lends itself 

 readily to a vari- 

 ety of methods of 

 handling and with 

 proper facilities can 

 be grown at almost 

 any season of the 

 year. In fact, all 

 the larger markets 

 of the country are 

 at present supplied 

 with lettuce every 

 month of the year. 



FIG. 101. Cos lettuce, var. Romana 



Lettuce can no longer be spoken of as a crop of any special 

 season, for even at the North it is grown as a field crop in spring 

 and autumn and as a 

 forcing crop during 

 winter. At the South 

 it is treated both as a 



field crop and as a j // 



frame crop. In order 

 to treat the subject 

 adequately, taking into 

 account the conditions 

 under which it is pro- 

 duced, it will be con- 

 sidered, as a field crop 

 at the North ; as a 

 field crop at the South ; 

 as a frame crop ; and 



as a forced crop. 



FIG. 102. Asparagus lettuce, var. angustana 



