Bulletin 151, Truck and Garden Insects


 Several species are concerned in this injury. The most
abundant is Empoasca mali or bean leaf-hopper. This is also
called the apple leaf-hopper, because it was first noticed on
apples which it damages severely. It is a light green insect,
V/8 of an inch long. Under a lens the eyes of the living insect
are white but they quickly turn brown after death. The bug
lives on a variety of plants but is partial to cowpeas and beans.
There are many generations a year.
 Control.-These insects can be killed by a strong tobacco
extract. A successful one is:
 Black leaf 40................... .... .......................2/5 pint
 Soap .......................... ... ....................... 5 pounds
 W ater ......................................................... 50 gallons
 Kerosene emulsion will also kill them but there is more
danger of burning the delicate plants.
 Spraying for this pest is expensive and not altogether sat-
isfactory because the plants are quickly reinfested from sur-
rounding vegetation. Some relief may be obtained by destroy-
ing grass and weeds about the edges of the field. Beans should
not be planted too near a field of cowpeas. In a small patch
the leaf-hopper can be caught in an ordinary insect net, made
of fine-meshed cloth, such as muslin. The net should be fre-
quently dipped in kerosene to destroy the insects caught.
 If one has a large acreage it will pay to use a machine for
 catching these pests. Such machines are constructed on the
 plan of the well known hopperdozers for catching grasshoppers.
 They consist of a vertically placed framework mounted on
 runners for drawing over the field. The bottom edge of the
 frame is placed at a height sufficient to strike the tops of the
 plants as it is drawn among them, causing the insects to jump.
 This frame is covered with either a smooth polished metal or a
 canvas smeared with a sticky substance in which the insects
 are caught. If the hoppers strike the smooth metal they will
 slide into a trough of kerosene or into a box-like trap fastened
 to the lower edge of the metal. If the canvas is used, smear it
 with tree-tanglefoot diluted with castor oil to the proportion of
 1/4 pint to each pound of tanglefoot. A cheap commercial grade
 of castor oil is used and the coating will need to be renewed for
 every 5 acres. These hopperdozers are illustrated in Farmers'
 Bulletin 737, United States Department of Agriculture, from
 which the foregoing recipe was taken.*
 *See also page 202, Control of Bean Leaf-hopper.