190 TRUCK-FARMING AT THE SOUTH. 



aration of the ground for these and for other onion sets 

 is the same as for the crop from seed. 



The sets are pressed into the soil at the distances the 

 crop is to mature, the tops about level with the surface, 

 care being taken to have the root end down. The sets 

 should range in size from that of a pea to a common- 

 sized marble. The smaller the better. When the bulbs 

 are too much developed, they are apt to run to seed in- 

 stead of producing good onions. Onion sets are often 

 high-priced, costing from five to ten dollars per bushel; 

 but they may be grown at the South with proper manage- 

 ment. The land should certainly be free from weeds and 

 grass, lighter and less richly manured than for the crop. 

 The rows may be ten inches apart, and the seed should 

 be sown late in the season, about May 1st, and much 

 thicker than when intended to produce large bulbs. 

 From fifteen to twenty pounds to the acre are required. 



INSECTS. 



The larvae of the Dipterous, or Two-winged insects, 

 which at present infest the onion in this country, pene- 

 trate it at the root; and the first indication of their pres- 

 ence are symptoms of disease and approaching death. 

 There is no remedy, but to dig up every wilted and 

 yellow plant, and to hunt for and destroy the grub with- 

 in the rotting bulb, with a view to curtail future depre- 

 dations. 



The black Onion-fly (Ortalis flexa), is a native of 

 this country, while (Anthomyia ceparum,) is an im- 

 ported insect. 



