Q: How did the artillery fungus get in my mulch? My neighbors do not have it – only me! Why me!
A: This is extremely difficult to answer. The artillery fungus commonly occurs
on dead trees, dead branches, rotting wood, etc. throughout the Northeast. I
have seen it in the forest on standing dead trees and limbs on the ground, as
well on wood in mulch-producing yards. If infested material is used for mulch,
the artillery fungus may be already in the mulch when the load of mulch arrives
at a job site, and may then grow rapidly along your foundation during cool moist
conditions. However, this is likely a problem only when mulch is not composted,
which subjects the mulch to higher internal temperatures.
masses may already be present at a site on old mulch, previously infested plant
leaves, rabbit or deer droppings, decaying leaves, and grass. These existing
spores may immediately infest new applications of mulch. In some cases, the
spores also may be transported for very short distances via wind from adjacent
infested sources. Spores may also be brought to the site on infested nursery
plants, by being stuck to the undersurface of leaves, if the nursery also had an
artillery fungus problem. When the leaves fall off onto the mulch the attached
spores inoculate the mulch… here we go again!
People can also spread the artillery fungus in various ways. Some homeowners make the mistake of sanding, scraping, or otherwise removing the spore masses from the sides of their houses, and letting them fall onto their foundation mulch. Such spores are dormant, but very much alive. They germinate and infest the mulch.