Willow Leaf Ficus Attacked by Gregarious Moth Caterpillars

I accidentally got interested in Bonsai through work interactions. I started to go through all postings to find my topic of interest, but decided just to add a new post. Here in Florida there is a wonderful collection of Bonsai at Heathcote Botanical Gardens. But their willow leaf ficus plants have been attacked by a cateripillar, which feeds enmasse on bark creating lots of frass and damaging trunk and limbs. I reared them out and had them identified at the Smithsonian -- Xystrologia grenadella Walsingham, a member of the moth family Tineidae (which as a group are called clothes moths). There isn't hardly any information on this pest (geographical distribution, chemical control, biolgical control, life history, etc), although it appears it may have originally been from Grenada. Does anyone know anything more about this pest? The damage is significant, but I cannot yet be sure if the pest works alone or if there is another factor involved (like perhaps the adult moths are attracted to lay eggs on a plant that already has some ill condition). Only the willow leaf ficus plants are attacked. Thanks, David

I wouldn't bother looking for more esoteric information. The botanical garden should have enough sense to spray the trees with an appropriate insecticide.
Iris