MASS. EXPERIMENT STATION BULLETIN 424 



Table 5. — Bushels of Different Size Sets Required to Plant an 

 Acre at Varying Distances Between the Rows and in the Row. 



Cultivation and Weeding. — Keeping a field free of weeds is one of the most 

 important and also one of the most expensive operations in the growing of a crop. 

 It has been estimated that cultivating and weeding make up nearly 40 percent of 

 the total labor cost (1). Because of the small, shallow root sj'stem and the up- 

 right growth habit and round structure of the onion leaves, which provide rela- 

 tively little shade, the plant is a poor competitor against weeds. If weeds are 

 not kept in check, yields are low, harvesting is difficult and costly, and losses from 

 rots are usually large both in the field and in storage. While the principal ob- 

 jective of cultivation is to control weeds, many growers feel that frequent stirring 

 of the ground, particularly after heav}' rain, is also beneficial to growth. 



As a rule, onion fields in the Connecticut Valley in the past were well cared for 

 during the growing season. Much of the crop's success can be credited to this 

 one fact alone. The farmers who actually tended the crop were willing to hand 

 cultivate with wheel and "shove" hoes six to eight times during the season and to 

 perform the arduous, time-consuming task of carefully removing the remaining 

 weeds from each row by hand. 



Many growers with small acreages will continue to grow their onions in this 

 manner, for in this way they are able to get maximum acre yields. Rows are 

 planted close together and, if care is exercised in cultivating, little injury is done 

 to the onion plant. Large growers, on the other hand, are willing to accept less 

 than maximum acre yields if they can use small tractors for at least part of their 

 cultivation and thereby reduce production costs. When tractors are used, how- 

 ever, rows must be spaced further apart, with 14-inch rows as a minimum. 



Tractor Cultivation has proved satisfactory during the early part of the grow- 

 ing season, but as the crop develops increasing care must be exercised. The root 

 system of the onion is not extensive, and serious injury to any part of it will be 

 reflected in reduced vigor and growth of the plant. The roots grow out laterally 

 from the base of the bulb for several inches before they turn down. It is easy to 

 see how the passage of garden tractor wheels between narrow rows might result 

 in serious injury to the plant after the lateral roots have developed. This in 

 turn would result in reduced yields. It is also obvious why frequent shallow culti- 

 vations are to be preferred to less frequent deep ones. 



After the crop is well along, some hand cultivation and hand weeding is usually 

 necessary to supplement the use of tractors. It is doubtful if an onion crop can 

 be entirely grown with tractor cultivation as long as the practice of planting in 

 narrow rows is adhered to. 



