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The Moreton Bay fig tree at the east
end of Henry Street, Toowoomba.
The two trees
in the background are large Chinese elms
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The Moreton Bay fig tree at the
eastern end of Henry Street in Toowoomba is the finest specimen of its species
in the city. The tree is on private Federal Defence Department land and should
not be approached more closely than the gate, which anyway gives a very good
view of the tree. The tree was planted by Eric Albury French of Toowoomba
before he left to fight in the First World War, ‘to be remembered by’. Eric
French became a Warrant Officer 2, fought in France, and returned safely from
the war.
The tree is one hundred years old.
The trunk is two to three metres thick, and the canopy is 27 metres wide and 24
metres tall.
Moreton Bay figs (aka Port Jackson
figs in New South Wales) occur naturally along the east coast of Australia in
wet and dry rainforest, and in south-east Queensland reach their furthest
inland location along the Great Dividing Range. They are commonly massive and
magnificent trees, typically with several short thick trunks arising from a
wide spread of buttress roots. The trees generally develop low thick
wide-spreading branches close to the ground and an immense rounded canopy of
large leathery dark green leaves. Spherical green flowering bodies (syngonia)
develop among the new leaves in spring, and ripen into edible mottled purplish
fruits about two centimetres across in late summer.
The tiny seeds of Moreton Bay fig
trees are spread by fruit-eating birds, bats and possums. They may either
germinate in the ground (like this tree) or in the canopies of other trees, in
which case they become strangler figs. The trees that develop from seeds that
germinate in the ground vary considerably in form, sometimes with and sometimes
without spreading buttress roots, some with single tall slender trunks, others with
short thick trunks which branch into upward-spreading subsidiary trunks, and
some growing into the more classical shape of this tree in Toowoomba.
Moreton Bay fig seedlings that
germinate in the forks of other trees send down slender aerial roots to the
ground which later thicken, branch and fuse together around the trunks of their
host trees until they form such a tight outer layer that the host tree is
eventually strangled and dies. Toowoomba’s climate is too dry for any of the
native fig trees to develop prop roots descending from horizontal branches to
the ground.
Moreton Bay fig trees are not only
impressive and beautiful, but they are also very important sources of habitat
and food for a wide range of local native fauna; they may also be hosts to epiphytic
ferns and other plants. Whilst their leaves and fruits are consumed by a
variety of insects and their dead wood by termites, their greatest ecological
value is the ripe fruits which provide food for many species of native birds,
bats and mammals, all of which spread their seeds.
Moreton Bay figs (and all other species of figs)
have unique flower and fruiting bodies called syngonia. Syngonia are spherical,
with an internal cavity lined with hundreds of minute male, female and sterile
flowers. The cavity is connected to the outside by a narrow passageway lined
with backward-pointing hairs. During the development of the syngonia tiny wasps
which are specific to each species of fig enter them through the narrow
passageway. Trapped inside, the wasps move around, mate, lay eggs on the
sterile flowers and pollinate the female flowers (resulting in the seeds inside
edible figs). The wasp grubs feed inside the ripening fruits then eat their way
outwards, pupating under the skin before escaping as adults to seek out other
developing syngonia to enter.
(Article by John Swarbrick)
