Little is known regarding the enemies of the litchi in China. Brewster says: "There is a worm which makes a ring around the trunk under the bark. When the circle is complete the tree dies; but the bark is broken by it, and by careful watching this can be prevented before the worm does serious harm. There is also a sort of mildew upon the leaves in certain years that does much harm, and the Chinese do not seem to have any way of dealing with it."
Several insect pests are reported from India. A small brown weevil (Amblyrrhinus poricollis Boh.), the larvae of a gray-brown moth (Plotheia celtis Mo.), and the larvae of Thalassodes quadraria Guen. feed on the leaves. The larvae of Crypto-phlebia carpophaga Wlsm. attack the fruits. Several species of Arbela (notably A. tetraonis Mo.) occur as borers on the tree.
It has been found in Hawaii that the dreaded Mediterranean fruit-fly does not attack the litchi fruit, except when the shell has been broken and the pulp exposed. The litchi fruit-worm, the larva of a tortricid moth (Cryptophlebia illepida Btl.), is said to have caused much damage to the fruit crop at times. The hemispherical scale (Saissetia hemispherica Targ.) occasionally attacks weak trees. The larvae of a moth (Archips postvittanus Walker) sometimes injure the foliage and flowers. A disease which has been termed erinose, caused by mites of the genus Eriophyes, has been reported from Hawaii, where it has become serious on certain litchi trees. Spraying with a solution of 10 ounces nicotin sulfate and 1 3/4 pounds whale-oil soap in 50 gallons of water was found to eradicate the mites.
Plate XVII. The litchi, favorite fruit of the Chinese.