Plant galls have also been used in ancient and even fairly recent medicines. Galls were used in the 1700s in France supposedly to control fevers. Today galls are not used medically except in a few ointments. Galls sometimes have been used as food, or rather as a spice. It is aromatic and acidic in flavor and is used with honey for cooking.
Most galls taste similar to the host plant.
Some of the galls have a higher content of carbohydrate, as will be shown later for pinyon needle galls. Most plant galls, however, are injurious to crops, for example, the hessian fly, clover leaf midge, chrysanthemum midge, and pear leaf blister mite. In 1940, Felt gave approximately the same statistics. Gall insects concentrate on all parts of the plant, buds, leaves, petioles, flower heads, stems, bark, and roots. The part of the plant attacked helps in the identification.