Chicken of the woods (Laetiporus sulphureus): what the sources record

This page describes what four published sources say about one bracket fungus. It does not identify a fungus from a photo and says nothing about any single tree. The sources come from the United Kingdom and the United States. The parent page, wood decay fungi on trees, compares the fungi that have pages here.

Type of rot and hosts

The sources describe a brown rot of heartwood. The Woodland Trust says it makes a brittle brown rot that hollows out the heartwood and leaves the living sapwood untouched. The page on white, brown and soft rot compared sets out how the sources define the three types. The Woodland Trust says it grows mainly on oak and also names yew, cherry, sweet chestnut and willow, and gives the fruiting season as late spring to autumn. The TCI article says it attacks hardwoods, especially oaks. The University of California integrated pest management program covers the western species L. gilbertsoni and L. conifericola in addition to the sulphur-yellow species, which is why its host list differs from the UK one. It calls the group one of the few brown rot fungi of hardwoods, one of the most serious causes of decay in oaks and eucalyptus, and one of the few fungi that decay yew. It says the fungus enters through bark wounds and dead branch stubs.

What it looks like, and look-alikes

The Woodland Trust describes a thick, fleshy bracket, bright creamy yellow with bands of orange when young and fading to cream with age. UC IPM gives conks of 2 inches to over 20 inches wide, bright orange-yellow above and red-yellow below, produced each year and usually in fall, turning hard, brittle and white with age. The TCI article adds that the pores are so small the underside looks velvety, and that a salmon or beige form is a separate species, Laetiporus cincinnatus, still called chicken of the woods in common speech. Two look-alikes are named. The Woodland Trust gives the giant polypore, Meripilus giganteus, as very similar but brown. The TCI article gives hen of the woods, Grifola frondosa, which has much bigger pores.

What the sources say the conk can indicate

UC IPM pest note: says conks do not appear until many years after the onset of decay and indicate extensive internal damage.
TCI article: says aboveground symptoms are often not present, that annual conks usually appear in late summer through late fall, and that the fungus tends to associate with cavities and cracks, so it can sit in the canopy, the trunk or the buttress.
Washington State University extension sheet: describes brown rot as the less common type, caused by under 10 per cent of wood decay fungi and mostly found on conifers, with large strength loss early in the decay.

Management and who to ask

The sources do not describe a treatment that removes established heartwood decay. They describe identification, then assessment of the tree by a qualified person. See tree risk assessment methods and consulting arborist credentials. Where any source mentions chemical treatment, pesticide licences by country says who may apply products to trees.