No. 4.] ROOT CROPS. 147 



handle in that way; the rest are left to mature. Onions are re- 

 peatedly grown on the same land with decided success, and seem to 

 prove the exception to the rule of rotation. The standard varieties 

 of onions gTown by the market gardeners are Yellow Globe Danvers 

 and Southport White Globe; for transplanting, Prizetaker. The 

 Danvers is by far the most popular. The average yield of onions 

 is about 500 bushels per acre, although it is not unusual to obtain 

 as many as 800 to 1,000 bushels. 



Onions are easily stored, the requisites being, (1) proper curing 

 in the field; (2) even, dry temperature, between 35° and 40° F. ; 

 (3) good ventilation. One freezing will not seriously injure the 

 crop after it is put into storage, but repeated freezings and thawings 

 soon spoil it. If the crop is frozen, and is not allowed to thaw until 

 sold, little damage will occur. The market gardener usually handles 

 his crop in bushel boxes and does not attempt to hold many for the 

 winter trade. The average market price for dry onions is about 60 

 cents per bushel, while the early crop often sells for $1. 



The insect pests of onions are mainly two, the maggot and the 

 thrips. The onion n]aggot hatches from an es;g laid by a small fly 

 near the base of the plant. The egg hatches in a few days and the 

 maggot eats into the bulb, causing decay and spoiling the plant. 

 There is little that can be done, and the injuiy is not usiially so 

 extensive as to destroy a lai'ge i^ercentage of the crop. The onion 

 thrips is a small insect, not noticeable except to the close observer, 

 which eats the stalk of the onion. In a dry season it is likely to be 

 quite injurious. About the only satisfactory remedy is overhead 

 irrigation. 



Onions are attacked by one disease which is quite injurious when 

 once introduced. It is called onion smut, and lives in the soil from 

 season to season. The best remedy is rotation. It has been found 

 that an attachment to a seed sower whereby the seed and adjacent 

 soil can be moistened by formalin will largely control the disease. 

 Dr. George E. Stone of the Massachusetts Agricultural Experiment 

 Station has developed this treatment. 



