September, 1941 
the same time such an active insect, that no 
satisfactory method of control has been de- 
veloped. 
The garden flea hopper, Halticus bracte- 
atus (Say), is a pest of considerable impor- 
tance on white clover and other leguminous 
crops in Illinois. In Missouri, it sometimes 
destroys garden bean crops completely. In 
South Carolina and neighboring states this 
tiny bug occasionally destroys 50 to 60 per 
cent of the alfalfa crop. 
The cotton flea hopper, Psallus seriatus 
(Reuter), is a serious pest of cotton, more 
important in Texas, Oklahoma, Georgia and 
South Carolina than in Illinois. In some 
years it is reported as causing greater losses 
than the boll weevil. Both nymphs and 
adults of this flea hopper feed on the tiny 
flower buds of cotton, causing them to drop; 
the feeding habits of the bugs may also cause 
the plant to grow tall and spindly, resulting 
in a light set of cotton squares. This insect 
may be controlled in cotton fields by fine 
sulfur dusts. Almost complete freedom from 
damage may be obtained by the use of these 
materials. The abundance of this insect is 
dependent on certain ecological factors, par- 
ticularly any condition that favors abundant 
growth of the wild hosts, the various species 
of Croton. 
The apple redbug, Lygidea mendax Reu- 
ter, a potential pest of apples in Illinois, 
has not yet been found in this state. In 
parts of the East it is very abundant. Its 
feeding causes dents or dimples in the apple, 
and areas of hardened tissue which throw 
the fruit out of grade. It also damages the 
apple crop by feeding on small fruit, causing 
excessive shedding of the apples, with scars 
and malformed fruit if growth continues. 
Some infested orchards have had at picking 
time 25 to 30 per cent of the fruits culled 
out as a result of malformations caused by 
the redbug. 
This species is easily controlled by adding 
nicotine sulfate to the pink bud spray or by 
nicotine dusts, since the nymphs are delicate 
and very sensitive to these materials, but in 
Illinois it is not now necessary to put on an 
application for their control. 
The four-lined plant bug, Poecilocapsus 
lineatus (Fabricius), attacks many cultivat- 
ed plants, such as currant, gooseberry, pars- 
nip, mint and some other truck crops, as well 
as dahlia and rose. In Illinois, it fluctuates 
greatly in abundance. In certain years it 
pays to apply a nicotine dust for its control. 
KNIGHT: PLANT Bucs, or MiripAgz, or ILLINOIS 13 
The bright red nymphs puncture leaves 
and tender shoots, sucking sap; every punc- 
ture produces a reddish spot, the leaves 
curling as the growth of the plant is checked. 
The pear plant bug, Neolygus communis 
Knight, may leave its natural host, dogwood 
(Cornus sp.), and colonize on pear trees. 
The nymphs feed on the small pears, causing 
Fig. 14.—Mirid injury. 
leaves of ash (Fraxinus sp.) are feeding punc- 
tures of plant bugs, in this case Neoborus amoe- 
White spots on 
nus. This type of injury is typical of most 
mirid feeding. 
