Ganoderma australe

(Fr.) Pat.

A mature bracket with multiple growth increments on beech in the New Forest, Hampshire.
A developing bracket with a wide margin on a dead oak in Sevenoaks, Kent.
Several mature brackets at the base of larch in Maidstone, Kent.
The chocolate brown flesh and tube layer from a bracket on a pine stump near Sittingbourne, Kent.
An aberrant fruiting morphology on an oak stem in Basildon, Essex.

A mature bracket with multiple growth increments on beech in the New Forest, Hampshire.
A developing bracket with a wide margin on a dead oak in Sevenoaks, Kent.
Several mature brackets at the base of larch in Maidstone, Kent.
The chocolate brown flesh and tube layer from a bracket on a pine stump near Sittingbourne, Kent.
An aberrant fruiting morphology on an oak stem in Basildon, Essex.
New fruit body emerging beneath a senescent fruit body on beech in Richmond, UK.
Numerous brackets including broken brackets on beech in the New Forest, UK.
Senescent tier of perhaps only three brackets on beech in the New Forest, UK.
Brackets growing within an open longitudinal cavity on beech in the New Forest, UK.
The brown spore released from teleomorphic fruit bodies.

Common name

Southern bracket.

Often found on

A very wide range of broadleaved species.

Sometimes found on

conifers (notably larch and pine).

Location

Found fruiting from structural roots up to the lower crown (more rarely including scaffold limbs). Can proliferate extensively amongst lapsed pollard heads.

Description

Perennial. Grows singularly or in tiers. Tough and woody. Chocolate brown surface – sometimes algal-stained. Ribbed white sometimes (usually younger specimens). Young fruiting bodies begin as white masses. White pore surface. Deep tube layer. Chocolate brown flesh. Brown spore. Upper cuticle consistently 1mm+ in thickness. Can become very large. May grow for many years. Rarely anamorphic or aberrant in morphology.

Confused with

Ganoderma applanatum (very thin outer crust).

Significance

Parasitic and saprobic. Can breach reaction zones. Attributed to a selective white rot . Trees with poor compartmentalisation ability / lacking true heartwood are often quickly hollowedout. Prompts buttress development. Can cause structural failure via windthrow / collapse and stem fracture. Hollowness and stability investigations are very necessary, where significant targets exist. Likely that all UK examples are Ganoderma adspersum – likely not a synonym of G. applanatum.