The devices and implements used for fighting plant enemies are of two sorts:(1) those used to afford mechanical protection to the plants; (2) those used to apply insecticides and fungicides.Of the first the most useful is the covered frame. It consists usually of a wooden box, some eighteen inches to two feet square and about eight high, covered with glass, protecting cloth, mosquito netting or mosquito wire. The first two coverings have, of course, the additional advantage of retaining heat and protecting from cold, making it possible by their...