What Is the Orange Jelly Blob on the Log? Identifying Witch’s Butter and Its Jelly-Fungus Kin

It is one of the odder things you can find on a fall walk: a dead branch or log that appears to have a blob of bright orange or golden jelly stuck to it, glistening in the damp, folded and lobed like a scoop of something spilled and left to set. Touch it and it is cool, slick, and rubbery — genuinely gelatinous, not slimy like a slime mold and not firm like a normal mushroom. Come back a few days later after things have dried out and it has shrunk to a hard, dark, crusty flake you would barely notice; then a good soaking rain arrives and it plumps right back up, bright and jelly-like again, as if it came back to life. These are the jelly fungi, and the best-known orange-to-yellow ones go by the wonderful common name witch’s butter. They are a harmless, fascinating, and very seasonal feature of cool, wet autumn woods. Here is how to know one when you see it.

How to Identify Witch’s Butter and Jelly Fungi

Several closely related fungi share the "witch’s butter" or "jelly fungus" look, and for identification you can treat them as a group by their unmistakable texture and habit:

• Jelly-like texture: the defining feature — soft, translucent, rubbery, and gelatinous, like set jelly or gummy candy, quite unlike the firm flesh of a typical mushroom or the dry felt of a bracket fungus.
• Bright warm color: most often vivid orange, golden-yellow, or amber; some related jellies are pale, whitish, or (in one common black species) dark brown to nearly black.
• Brain-like, lobed shape: it grows as irregular folded lobes, wrinkles, and blobs rather than having a clear cap and stem — no gills, no obvious stalk, just a gelatinous mass sitting on the wood.
• Always on wood: jelly fungi grow on dead or dying branches, logs, and stumps — usually hardwoods — not on the ground or on living healthy trees. A jelly blob on soil is more likely a slime mold instead.
• Reappears with moisture: it swells up glistening after rain and shrivels to a hard, inconspicuous crust in dry weather, rehydrating again and again over weeks — a hallmark of the group.

The true witch’s butter of European legend is a golden-yellow jelly, but in North America several look-alikes share the name and the look, including a common bright-orange species often found on the bark of fallen conifers and hardwoods. For everyday identification, a gelatinous, lobed, orange-to-yellow blob growing on dead wood that comes and goes with the rain is safely called a jelly fungus.

What It Is Doing There

Jelly fungi are decomposers — part of the vast cleanup crew that breaks down dead wood and returns its nutrients to the forest — and the visible jelly is the fruiting body, the spore-producing structure, of a fungus whose main body is a network of threads living inside the log. That is why they show up on dead branches and downed limbs: the fungus is quietly digesting the wood, and when cool, wet weather arrives it pushes out these gelatinous fruiting bodies to release spores. The rubbery, water-holding texture is the trick behind their disappearing act — jelly fungi can dry out almost completely, survive dormant as a hard flake, and revive to keep releasing spores whenever the next rain rehydrates them, stretching their spore season across the damp weeks of autumn. Interestingly, some orange witch’s butter species are not decaying the wood directly at all but parasitizing other wood-eating fungi living in the same log — a fungus feeding on a fungus.

Look-Alikes and a Word on Foraging

A couple of things are confused with witch’s butter. Slime molds — like the bright "dog vomit" slime mold that erupts on mulch — can look similar but grow on soil, mulch, and low plants rather than on dead wood, and they have a very different, non-gelatinous texture up close. Other jelly fungi in the same broad group include amber jelly, pale crystalline "jelly ear" and white brain-like species, and a black jelly fungus; all share the rubbery texture and wood-dwelling habit. On the question people always ask: jelly fungi are generally regarded as non-toxic and are largely tasteless, but this article is strictly about identification, not foraging. Never eat any wild fungus based on a description or a photo match — positive mushroom identification requires an expert and firsthand examination, and some dangerous fungi can be mistaken for harmless ones. Enjoy witch’s butter for the strange, beautiful thing it is, and leave eating wild mushrooms to those with expert guidance.

Quick takeaway: a bright orange or yellow, rubbery, brain-like blob of "jelly" growing on a dead branch or log — one that shrivels when dry and plumps back up after rain — is a jelly fungus, commonly called witch’s butter. It is a harmless wood decomposer, not something to worry about (and not something to eat).

Found a mysterious jelly-like blob on a log and want to know what it is? Snap a photo and let Spotter help you identify it — and discover one of the quiet recyclers keeping the fall woods healthy.