Every summer, I get calls from landscapers in Phoenix about Agave suddenly wilting and dying. It has to be a fungus, right? Well, sort of, but it is actually a rot that has been caused by the feeding of an insect called the Agave Snout Weevil. The Agave Snout Weevil enters the plant at the base where the larva eats the tissue, inviting decaying organisms also to start working on the Agave.
Once the larva has done its damage, the adult- that’s the one with the ‘snout’, will move on to lay eggs on its next victim. The weevil loves the Agave americana, Agave weberi and other larger agave species. Though multiple generations per season can sometimes occur, it is best to treat in the fall and again in the late spring when life stages are most susceptible. Preventative treatments are your best bet. If you see wilting, remove the plant and surrounding soil immediately so they don’t move to other nearby Agave.