GREEN HOLLY BERRIES - Have you noticed that some holly berries remain green all winter and never turn the color they are suppose to?  The problem is caused by a berry midge called Asphondylia ilicicola.  This insect belongs to the gall midge family of which several hundred are known to attack various trees and shrubs.  The larvae of most of them cause the formation of galls (growths or swellings on leaves or twigs (see oak galls)) by their feeding.  The adult gall midges are small, mosquito-like flies.  The midge larvae feed inside the holly berries preventing them from turning red or yellow in the fall.  Seeds of infested berries are aborted and the green fruits don't attract birds.  The larvae live and complete their maturation inside the undisturbed berries.  In the spring when the hollies are in flower, the berry midges emerge, mate and lay their eggs in the new, developing holly berries.