Devil's Dipstick Identification Guide

What the find looks like

You usually smell this one before you see it. Somewhere in a woodchip bed beside a path, a garden border, a mulched shrub planting or a shaded lawn edge, there is a sharp, sweetish, rotten odour, and when you track it down you find a slender orange-red spike standing more or less upright out of the litter, often bent like a horn, with a cluster of flies working over the darkened upper portion.

The overall impression is of a tapering spike rather than a mushroom: no cap, no gills, no ring, just a single hollow column that narrows steadily to a point. That absence of a distinct head is where the identification starts.

Step one: look for the egg

Before you touch anything, search the surrounding mulch. Stinkhorns emerge from a soft, roughly egg-shaped structure, and there are almost always more eggs nearby at various stages. They are 1.5 to 3 cm across, whitish to pale pinkish or buff, soft and slightly yielding, and each has one or more white cords running away from the base into the substrate.

Slice an egg vertically. Inside you should see the layered structure that confirms the group: a thin outer skin, a thick clear gelatinous layer, and, in the middle, the compressed pale column of the future fruitbody with a dark olive layer of spore slime already formed against it. If you cut an egg and find gills folded up inside, you are in a completely different group.

Step two: read the mature column

Stand the fruitbody up and measure it. Mature specimens are typically 10 to 17 cm tall and 1 to 2 cm thick at the widest point, tapering evenly to a narrow, often slightly curved apex. There is no separate cap sitting on top, no skirt, no lattice and no arms.

Colour is graded and that gradient is diagnostic. The base is pale — whitish, cream or pale pink — and the colour deepens upward through pink and orange to a strong orange-red or scarlet in the upper third. The transition is gradual, a smooth ramp of colour rather than an abrupt line.

The surface is spongy and conspicuously pitted or chambered, like a fine honeycomb, and the whole column is hollow. It is fragile in the hand: press too hard and it collapses. Very fresh specimens are stiff and turgid, but the whole fruitbody softens and slumps within a day or two.

Step three: the spore-bearing surface

This is the character that decides the species. Stinkhorns do not have gills, pores or teeth. Instead they carry a dark, sticky spore slime called the gleba, and where that slime sits is the key.

In this species the gleba is smeared directly onto the tapering upper portion of the column — usually the top third to top half — with no separate head, no swollen tip and no boundary line to mark where it starts and stops. Fresh, it is a dark olive-brown to almost black glistening coating. Once flies have removed it, the underlying surface is exposed and it is bright orange to red, deeply pitted and often slightly paler right at the point.

Run your eye over the join between the coloured and uncoloured zones. If there is a clean, abrupt boundary and the fertile region sits on a small distinctly demarcated head, you are looking at a different species in the genus.

Step four: the base

Excavate carefully. At the bottom of the column there is a persistent whitish to pale pinkish sac — the volva, the remains of the egg — loosely wrapping the base. Note that it is a soft, thin, sometimes slightly gelatinous bag, not a firm cup.

From the underside of the volva, one or more white cords run off through the substrate. Follow one and it usually leads into buried woodchips or rotting wood fragments. Recording that connection is worth the extra minute, because substrate is a supporting character for the whole group.

Step five: flesh, section and colour change

Slice the standing fruitbody lengthways. You will see a single hollow tube with a spongy, chambered wall a few millimetres thick, coloured through rather than merely surface-coloured in the upper region. There is no separate stem tissue, no cap tissue, and no gill trace anywhere.

There is no bruising reaction to speak of. Handling makes the fragile tissue tear and darken mechanically, and the whole fruitbody discolours to dull brown as it deliquesces, but there is no crisp blueing or reddening on cutting.

Step six: spores, and why a print will not work

Do not bother laying anything on paper. There is no discharge mechanism that drops spores downward; the spores are embedded in the slime and are dispersed by insects that walk through it and carry it away on their legs and bodies.

If you want the microscopic character, take a smear of the gleba on a slide. The spores are tiny, smooth, hyaline to pale, and narrowly elliptical to cylindrical, on the order of 4 to 7 micrometres long by 2 to 3 wide — very small relative to most of the cup fungi and agarics.

Habitat and season

This is a decayer of woody debris, and in practice that means it is strongly associated with cultivated ground: hardwood mulch beds, woodchip paths, garden borders, compost-enriched soil, and the leaf-litter margins of broadleaf woodland. It fruits from late spring through autumn, with big flushes a day or two after heavy warm rain, and it often appears in loose troops rather than singly. Once you know a mulch bed produces it, expect repeat appearances in the same spot for several seasons.

Telling it from the other stinkhorns on morphology alone

Dog stinkhorn. The closest confusion. That species is markedly smaller and more slender, its column is whitish to pale cream for nearly its whole length, and the fertile region is confined to a small, slightly swollen, orange-red head that is clearly set off from the pale stalk by a visible line. Our species is bigger, colour-graded from pale base to red apex, and has no demarcated head at all.

Ravenel's stinkhorn. Shorter and proportionally stouter, with a distinctly pink to pinkish-red column and a more abruptly separated, slightly bulbous fertile head. The abruptness of that transition is the character to judge.

True stinkhorns of the genus Phallus. These have an unmistakable structure our species lacks: a white spongy stalk topped by a separate thimble- or bell-shaped cap, usually ridged or netted, on which the gleba sits, and in some species a lacy skirt hanging beneath the cap. If you can lift a distinct cap off the top, it is not this genus.

Cage and octopus stinkhorns. These emerge as multiple arms or a fused hollow lattice rather than a single spike; no confusion once open, though their eggs look similar.

Squid stinkhorns. Three or four orange arms joined at the tips and sitting on a short white stalk — again, several arms, not one column.

Eggs of other groups. An unopened stinkhorn egg can be mistaken for the universal-veil egg of an Amanita. Cut it: the Amanita egg is firm and contains a folded miniature mushroom with recognisable gills, while the stinkhorn egg contains jelly and a dark slime layer.

Field summary

One tapering hollow spongy spike, colour graded from pale base to orange-red tip; dark slime smeared directly on the upper third with no separate head; whitish sac at the base with white cords; woodchips or rich litter; warm months after rain; strong odour and flies in attendance. That set of characters is stable and quick to run through.