Mushrooms at the trunk: sometimes lawn, sometimes a deadline.
Mushrooms in mulch after rain are Florida being Florida. A hard shelf growing FROM the trunk or root flare is different — that’s a fruiting body of internal decay, and on palms it has a name with no cure.
Soil or trunk — that’s the whole question. Mushrooms popping from lawn or mulch after rain, even in rings near a tree: decomposers doing yard work, almost never a tree problem. A firm, shelf-like growth attached to the trunk itself or the root flare — tan, woody, sometimes varnished-looking: that’s a conk, the external fruit of internal decay, and it never means nothing.
If it’s on a palm
A conk on the lower few feet of a palm trunk is the signature of Ganoderma butt rot. UF’s position is unambiguous: all palm species are susceptible, there is no treatment or prevention, and by the time the conk appears the internal decay is advanced — the palm should come down before wind makes the schedule. Two practical additions: don’t replant a palm in the same spot (the fungus persists in soil), and don’t move the conk around the yard — it’s the spore factory.
If it’s on a hardwood
Serious, with nuance. Decay fungi on oaks and other hardwoods confirm rot is present but not how much sound wood remains — a tree can hold a conk for years or fail next month, and the difference lives in location (root-flare conks worry us most), species (a laurel oak with conks is a different conversation than a live oak), and what the tree overhangs. This is an in-person assessment, ideally before storm season rather than after.
What you can do today
Photograph the growth up close, the whole trunk base, and the full tree; note whether the shelf is hard or soft and whether it’s actually attached to wood. Text the set to (727) 761-8618. Don’t knock it off (the decay doesn’t care, and the evidence helps diagnosis), and until it’s been looked at, stop parking under the tree — that’s not drama, it’s how we’d treat our own driveway.
Questions Cody hears every week.
What's the difference between lawn mushrooms and a conk?
Lawn mushrooms pop up from soil and rot away in days. A conk is woody or leathery, shelf-shaped, and attached to the trunk or root flare itself — it persists and hardens. Soil mushrooms near a tree are usually fine; a conk ON the tree means decay inside it.
My palm has a shelf growing from the lower trunk. How bad?
That pattern is the signature of Ganoderma butt rot, and UF’s guidance is blunt: by the time the conk shows, internal decay is advanced, there’s no treatment, and the palm should come down before it chooses its own moment. And don’t replant a palm in that spot — the fungus stays in the soil.
The conk is on my big oak. Same story?
Serious, but more nuanced than palms. Decay fungi on oaks tell us there’s rot, not exactly how much sound wood remains. Location matters — root flare conks worry us most. That’s a look-at-it-in-person call, and worth making before the next storm rather than after.
Tell Cody about your tree.
Three fields. He answers his own phone — you’ll hear back fast.
Faster: text a photo of the tree to (727) 761-8618.