Nearly every year cherry and plum trees in Iowa suffer a large amount of damage on account of the common pear-slug, or cherry-slug. While the control of this insect has not been considered a very difficult problem, yet it often happens that foliage is greatly damaged before the owner is aware that any slugs are on his trees.

During the years 1909 and 1910 the entomological section of this station undertook the study of this insect to determine the best methods of control. For three years it was abundant about Ames, and this outbreak offered good opportunity for its investigation. Its life history and the time of its appearance and of its generations were worked out and various sprays were tested. As a result many new facts were added to the knowledge of this common insect. In this bulletin definite information is given for the critical times to spray and the proper materials for spraying. It is hoped that the damage may be greatly lessened by the use of better methods of control.