ORANGE PESTS 



1493 



but the young males soon spin a small 

 white cocoon in which to pupate. Trans- 

 formation requires but a short time, the 

 two-winged males emerging when the 

 females are about half grown. After cop- 

 ulation the males die and the females con- 

 tinue to develop for some weeks or 

 months before egg-laying begins. 



During the spring months the young 

 are to be found in great numbers, but 

 by summer they have so hidden them- 

 selves as to give the general impression 

 that the pest leaves the trees during that 

 period. In the fall the adults begin to 

 deposit the large masses of eggs which 

 make them more conspicuous. The entire 

 strength of the female is converted into 

 eggs, only the shriveled and dry skin re- 

 maining after all have been deposited. 



The insect naturally hibernates during 

 the winter in the egg state, but due to 

 the uneven hatching caused by the warm 

 weather in the southern part of the state, 

 practically all stages of the young and 

 the adult males and females may be also 

 abundant during the winter months. 



Food Plants 



Works on a great variety of plants. The 

 fruit as well as all tender growing parts 

 of the plant are attacked. 



Control 



The control of this pest has been some- 

 what complicated and unsatisfactory, al- 

 though at the present time considerable 

 or complete success attends the efforts of 

 careful work. Without doubt the best 

 control measure is the application of a 

 carbolic acid emulsion spray, which 

 should be applied plentifully, from 10 to 

 15 gallons to an average size tree, and 

 under a pressure of 200 pounds. We 

 have found that two angle "Bean Jum- 

 bo" nozzles on a "Y" to each rod give 

 best results. Large-holed disks should 

 be used in the nozzles to insure a coarse 

 driving spray. 



If the mealy bug is present in great 

 numbers it may be necessary to make two, 

 three or even four applications a week or 

 so apart. 



During the winter, when there are large 

 numbers of egg masses, or in the spring 



when the young are hatching, is the best 

 time for applying the sprays. 



Fumigation has often given excellent 

 killing results, but is not at all recom- 

 mended for this pest, unless some other 

 destructive scale insect, such as red, yel- 

 low, black or purple scale, is present and 

 needs that treatment. Experience has 

 shown that an excessive dose gives little 

 better result than the ordinary black- 

 scale dosage (one-half to three-fourths of 

 Schedule No. 1 at the end of this section). 



Natural Enemies 



The ladybird beetle, Cryptolaemus mon- 

 trouzieri, is the most important natural 

 check. 



Citnis Thrips 



Euthrips citri Moulton 



General Appearance 



The adult thrips are orange-yellow in 

 color, with the thorax and the second an- 

 tennal segment orange-brown. They are 

 very minute; so small as to be scarcely 

 observed by the average orchardist, be- 

 ing less than one-thirtieth of an inch in 

 length and one one-hundredth of an inch 

 in width. The presence of this insect is 

 usually ascertained by the work, which 

 consists in scarring the fruit in such a 

 way as to form nearly regular circles 

 around the stem and blossom ends, al- 

 though these scars may extend almost 

 over the entire surface. They also cause 

 a characteristic crinkling and thickening 

 of the young citrus foliage, just as the 

 buds are unfolding. 



Life History 



The winter is spent in the adult form, 



which hibernates in various protected 



places. The thrips become especially 



abundant about the time the citrus trees 



are in bloom and begin their work as 



soon as the petals fall and continue 



throughout the summer. The eggs are 



laid from May to August, hatching in six 



or ten days. The larvae greatly resemble 



the adults but are at first somewhat 



lighter in color. In from six to eight 



days they change into the pupal stage, 



and in another three to five days become 



adult insects. The entire life cycle, from 



the laying of the egg to the beginning 



