However, new plants will rapidly reestablish from severed rootstocks as small as 2 cm and from a depth of 120 cm. Mowing will reduce the number of viable seed produced. However, the plants will persist due to vegetative reproduction. Mowing after initial seed set is not recommended and will likely increase seed dispersal. The gall midge has four to five generations per year and attacks all known biotypes of skeletonweed.
Females insert eggs below the surface of rosette stems and leaves.
The larvae feed on the leaves and stems at the site of egg deposition. This results in the formation of galls which are circular, slightly raised, approximately 3 mm in length, and yellowish to maroon in color. Infested plants show reduced vigor and early senescence, with decreases in viable seed production and stem size and length. Heavily infested stands may appear a purplish color from a distance. This midge and the mite are available for distribution in California.