The fruit bodies of Armillaria are mushrooms in which the cap is held atop a central stem. The mushrooms grow from live or dead wood and may appear in dense clusters with overlapping caps. Caps may grow to ten centimetres in diameter and be greyish (possibly also with brown or pinkish tints), greyish-yellow or yellow-green (but then a fairly drab, rather than bright, shade). The gills are more or less cream coloured and the range of stem colours is similar to that listed above for the cap.
An immature mushroom has a partial veil (a membrane that covers just the gills). As the cap opens out this membrane breaks and the bulk of it is left as a ring or skirt of tissue on the upper part of the stem. Sometimes there is also a remnant left as a raggedy edge to the margin of the cap.
Spore print: white. With overlapping caps, many spores released from the gills of one cap will fall onto the surface of the cap below and so it is to see a white spore deposit on the lower of two caps.
Armillaria sp. is listed in the following regions:
Canberra & Southern Tablelands | South Coast | Hume
Places
Yackandandah, VIC