Two Burls and a Lignotuber

Description:

2 large rounded outgrowths from a tree trunk near the base. They seemed to be part of the wood of the trunk. Smaller burls were seen on the other side. The tree trunk seemed to be arising from a swollen base with rough bark - this could be a lignotuber.

Habitat:

Spotted this tree on a nature strip. This is not growing in a fire prone area however, could have been affected by drought over the last 12-15 years.

Notes:

Unfortunately, I am not able to identify this tree except that it is a kind of eucalypt (could be eucalyptus, corymbia or angophora). Burls grow for trees that have undergone stress -fires, injury, pest infestation or drought. The growth of new buds is affected and these grow into rounded protrusions from the trunk. Some trees have lignotubers which are starchy lumps that conitnue to feed the tree during hard times. According to Andrew Lyne from The Centre for Plant Biodiversity Research "Lignotubers occur in some but not all Eucalyptus species. They also occur in some Corymbiaspecies. Lignotubers are a woody swelling, partly or wholly underground and have been shown to contain a mass of vegetative buds and substantial energy reserves. Species that possess lignotubers are often those tolerant to fire, drought and defoliation. Those species that do not produce lignotubers are usually prolific seed producers and survive such disasters as fire with massive seedling regeneration."