Migratory Habits of White Fly.



Considerable interest has been aroused th discus-

sion of the White Fly problem. The White Fly,Aleyrodes citri,

is an insect that has probably been introduced in Florida some

twenty-five or more yearF ago. During its early history, the

insect was most abundant in the region about 'Gainesville and

Southward reaching through Ocala, Citra and -ea.-ing-th-+-.

places in central Florida. The citrus trees are the principal

food plants of economic importance. The native plants of Flor-

ida, as a rule, prove distasteful to the insect. As it multi-

plies with very great rapidity and has 0 few enemies outside of

the fungi, an. the latter not very generally distributed, the in-

sect frequently occurs in overwhelming abundance.

The principal.times of flight are in the early morning

and in the early evening, especially about sun down. In the

present year while the August brood was flying, the insects were

so abundant at'Lalke City that ladies and children were practi-

cally driven off of the street during this portion of the day.

By making careful observation upon various food plants

and the intensity.of infection it weold ernn discovered that

the swarming of the white fly was practically limited to the lo-

cations where the insect occurred in such abundance that the host

plant had been practically exhausted and prevented from produc-

ing additional.growth. The females are instinctively attracted

to the new growth of the host plant before depositing their eggs.

By visiting several places in the State during the time













of the August brood, it was discovered that the conditions were

quite uniformly the same. Whenever the insect becomes so abun-

dant as to cut off prospects of food supplies for the future gen-

erations, th: mature insect appears to instinctively fly very

high and in gr.at numb.'rs. During these high flights it is a

ver;.- simple matter forz th,. winds to blow the insect, for a very

considerable c0istance. 4 inga t4A e P1 ght tho meat.ure -



These observations have a very important bearing upon

the quest of cntrollithe qstiothe ,white fly. the nun- /

ber -of white flies can be sufciently redu ed b, natural or a-ti-'

ficial means p down d Int

-r ;snfection .,of now lc itie. China berry, Umbrella trees,

and Cape Jessamine are the most severely infected ornamentalsJ

f ie districts where citrus growing is an important industry

these plants should be eliminated.

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