Wambo Coal AEMR 2011-2012 - Peabody Energy

Results
The onsite population of A. pendula occupies approximately 2.5 hectares adjacent to the
southern bank of North Wambo Creek. This population has been divided into two areas
that have been fenced to prohibit the ingress of livestock. A (fenced) vehicular track
bisects the two areas.
Age Cohorts
Several age cohorts were evident. These ranged from large specimens (up to 9 metres
tall) to seedlings less than 0.1 metre tall with several age classes in between. At the time
of the inspection the number of larger specimens were equalled or surpassed by the
number of seedlings (0.1 to 1 metre) and juveniles (1 to 3 metres).
Recruitment
Successful recruitment is evident by the presence of numerous healthy seedlings and
juvenile specimens. These new recruits were located within some small areas and are
probably the progeny of a few older specimens that have had an opportunity to set seed.
Health
Many of the larger specimens of A. pendula have substantial small deadwood in the
lower two thirds of the foliage and branches, commonly with only the uppermost third of
the crown holding live foliage. It was noted during the initial (baseline) inspection in June
2011 that many of the larger specimens were host to a large number of parasitic
mistletoe, in particular Amyema pendulum. A number of the larger specimens with
multiple mistletoe infestations show very poor health or are dead.
A number of A. pendula specimens were also found to be host to gall forming insects or
borers as evidenced by the presence of smooth woody nodules or clumps of particulate
wood on the branches of many of the A. pendula specimens.
Infestations
As stated above, many of the A pendula specimens within the local population have
infestations of Gall forming insects and borers. Acacias in general are often known to be
hosts to galls and borers, however high numbers of these can detrimentally affect the
health of the plant by re-directing nutrients and weakening the physical structure of the
plant.
Amyema pendulum (Mistletoe) is a parasitic plant that is tolerated in small numbers,
however, many of the Acacia pendula specimens that were found to be in poor health or
dead were also found to be host to multiple (up to 7 or 8) mistletoes.
Senescence
A large number of the larger specimens (approximately 12 to 15%) have recently died
and are now standing deadwood. This is a part of a natural process for a stand of
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