NATURAL COISTTROL OF CITRUS MEALYBUG IN FLORIDA. 



11 



The earliest seasonal record of the appearance of the fungus is 

 June 13, 1921, when it was found at Winter Haven. While not abun- 

 dant on this date there was considerable evidence to show that it 

 had been present for some time previously. As the graph (Fig. 1) 

 indicates, it became increasingly prevalent week by week up to 

 August 8, when the last examination was made. At this date so widely 

 scattered were the live mealybugs that a collection of representative 

 specimens was made with difficulty. 



Mealybugs of citrus in Florida are more prevalent upon grape- 

 fruit than upon orange. (See Fig. 2.) On such trees their favorite 

 .feeding location seems to be upon the fruit itself, or upon the fruit 

 pedicels, where they form more or less well-defined colonies. At . 

 times they occur along the under side of large branches or limbs o-f 



cuire coLLEcrED 



JU/vE/3 \JU/VE22 



JUNE 29 



JULY 6 



JULY /4 



Jl/ty 22 



AUG. 8 



TOrylL /VO COLLCCTED 



^ 406 



524 



4-75 



J50 



338 



260 



295 



DEAD EPQM D/SEASE 

 AT DATE OF COLLECr/O/V 



// 



28 



76 



67 



69 



94 



/02 



TOTAL OEAD EffOM^ 

 D/SEASE 7 OAV^ /irTu.9 

 DATE OF CO/.LECT/0/V 



4S 



/06 



J/3 



289 



3/2 



226 



273 



. 



/OO 

 90 



(^ 50 

 po 



/O 



o 









































^^ 





















.^— ■ 



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y 























/ 



/ 























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Fig. 1. — Data on collections of citrus mealybugs infected with Entomophthora fumosa. 



the tree, although it is not known whether they are feeding or not. 

 Mealybugs which frequent such situations are usually those which 

 are ovipositing or about to oviposit. In most instances such insects 

 are envelopjed in a mass of wax, the excretion of which precedes or 

 accompanies oviposition. Such a habit favors the spread of the 

 mealybug, because the young crawlers hatching from the eggs will 

 settle, in most instances, upon fresh fruit or twigs some distance 

 away from the spot where the adults found their food. It is not to 

 be inferred that mature females do not also lay eggs upon the fruit, 

 but rather that young feeding individuals are not usually found upon 

 the large branches. The habit of colonization, therefore, together 

 with the white, grayish, or pinkish color of the healthy insects, ren- 

 ciers their detection a simple matter. 



The grove at W^inter Haven was regarded as heavily infested. It 

 was estimated on June 13 that 75 per cent of the trees were sup- 

 porting five or more large colonies of the mealybug, that 20 per 



