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but tender young shoots and maturing fruit are greatly preferred. 

 Among the crops injured are tomato, potato, sweet potato, beans, 

 cowpeas, radish, cabbage, turnip, mustard, okra, etc. In autumn and 

 early winter the insect sometimes becomes a serious pest in Citrus 

 groves, feeding especially upon the fruit, young seedlings and yoimg 

 shoots of older trees. Similar infestations have been reported in 

 pecan groves. 



Notes on its habits and life-history studies have been made at 

 Gainesville, Florida. Hibernation is imperfect, about one-half of the 

 individuals remaining upon succulent plants in the field throughout 

 the winter months. No breeding takes place during the winter. 

 Eggs have been foimd outdoors during the second week of April and 

 as late as 12th December. The eggs are deposited in clusters, mostly 

 on the under-side of the leaves. 



The minimum period for incubation was 4 days. The minimum 

 time for the five nymphal instars, based on individual records, was 24 

 days. This gives a total of only 28 days from the time the eggs are 

 laid until the adult state is reached. Field records indicate that there 

 are four generations annually at Gainesville, and probably five in the 

 southern portion of the State. Development is more rapid during the 

 summer, temperature having an important bearing upon the period 

 of development of both eggs and nymphs. 



Of six predaceous enemies recorded in the field, the bug, Euthy- 

 rhynchus floridanus, is the most important ; three parasites of the 

 adult and two egg-parasites have been reared. Of 800 adults of Nezara 

 viridula collected in the field durmg the latter part of May and the 

 beginning of June, 38 per cent, were killed by two Dipterous parasites, 

 31 per cent, by a Tachinid, Triclioijoda pennipes, and the rest by a 

 Sarcophagid, Sarcophaga sternodontis. Both of these flies were also 

 bred from a number of other plant-feeding insects in Florida. The 

 egg-parasites were not common at Gamesville and are represented by 

 undescribed species. 



When valuable garden and truck crops are heavily infested, hand- 

 collecting seems to be the best control method. The proper manage- 

 ment and cutting of the cover or soiling crop will usually keep the insects 

 under control in Citrus and pecan groves. In case of severe infestation 

 of Citrus it has been demonstrated that hand-collection with large 

 nets can be done successfully and profitably. In using large nets 

 the work should be done m early morning or on cool days when the 

 temperature is below 70° F. At a higher temperature many of the 

 adult bugs will save themselves by taking flight before they drop into 

 the nets. 



Of both wild and cultivated vegetation the insects generally show a 

 decided preference for leguminous and cruciferous plants. During ' 

 late autunm, winter and early spring the bugs often congregate upon 

 cruciferous plants such as radish, coUard, rape, mustard, turnip, etc. 

 Some of these might serve as a valuable trap-crop at these seasons. 

 Experiments during the summer show that radish and collard, both 

 growing in the same row, will serve as a trap-crop to protect tomatos. 

 The seed should be planted about 1st November so that the radish 

 will be forming pods while the fruit of the tomato is developing and 

 ripening duruig the following spring. The insects should be gathered 

 by hand. 



