Readers’ wildlife photos

Today we have the second part of a two-part post on Australian trees, the eucalypts, contributed by Reader Dean Graetz. (Part 1 is here.) Dean’s captions are indented, and you can enlarge the photos by clicking on them.

The Trees that identify Australia

Australia is one of many countries that include plants as part of their identity.  The national floral emblem is the Golden Wattle (Acacia pycnantha), one of more than 1000 Acacia species found on the continent.  The two colours of the plant represent the essence of the continent.  The golden flowers represent its beaches, mineral wealth, grain, and wool harvests.  The green of the (leathery) leaves imitates the continent’s forests and productive landscapes.

Sparsely located in the arid heart of the continent is this visually striking tree.  Commonly known as the Ghost Gum, it was recently renamed with an appropriate Aboriginal Australian species word (Corymbia aparrerinja).  A much more impressive image is here.

Similarly, sparsely located in the drier areas of the continent is this tree.  Evocatively named Bloodwood (Corymbia opaca), there appears no external colouring which supports that name.\

However, if you manage to find a seeping wound, then the reason for its name will be obvious, the colour of the exuding sap (Kino) is a vivid.

When sedentary farmers and graziers were added to Australia’s population, substantial areas of eucalypt woodland, about 13% of the continent, were transformed.  Trees were either clear-felled and burnt for cropping, or just thinned for pastures.  This satellite image shows a large area of mallee, a eucalypt woodland type (dark), cleared in part for growing (wheat) on the bright sandy soil.  The sharp boundary on the LHS is a state border.  Multiple millions of eucalypt trees have been removed here and elsewhere for the reality of it is ‘Either Them or Us’.

Snow Gum woodlands lie on the snow line and are episodically burnt by lightning-induced bushfires, as here.  The many tall stems of each tree have been killed and have bleached white in the high UV environment.  However, the trees are not dead.  Each tree had developed a lignotuber, and from this a ring of new shoots have sprouted and will replace the tree’s burned canopy in about 5 years, or so.  Even so, the sea of bone white, dead stems is eye catching.

An ephemeral dry-country watercourse with three tall River Red Gums (Eucalyptus camaldulensis), the most wide spread Eucalypt, from lining the banks of permanent rivers to tapping the subsurface water of this small dry creek.  Never visually elegant or symmetrical, these trees, with their scrabbling roots and scarred stems, suggest one word: Survivor.

As does this extraordinarily large River Red Gum, possibly the largest and oldest known.  Residing in a cleared paddock, it is still healthily growing and supporting a large canopy.  Eucalypts do not annual ring, so its age cannot be measured, just guessed at 300+ years.  The gap in the trunk was likely generated centuries ago by a small fire lit close to it sheltering from the wind.  Repeated often enough to burn through the sapwood and into the heartwood, thereafter the weather and dry rot eventually hollowed the stem but left the sapwood continuing to thrive today.

All Eucalypts produce very hard, dense wood, which when dried after death, is difficult to saw or cut.  A few species are known ‘branch droppers’: large living branches just drop off, for no obvious reason.  Such species are also known as ‘Widow Makers’ for the fatalities of sleepers and sitters under the canopy.  The River Red Gum – see above – is well-known Widow Maker’.  However, branch shedding usually leaves large openings into the stem to be eventually hollowed out and occupied by parrots, such as this Sulphur-Crested Cockatoo (Cacatua galerita).  Because all Australian parrot species are hollow nesters, dead and holed Eucalypts are much sought after trees.

For an Australian away from the built environment, the visual presence of familiar gum trees reinforces your identity: you are home.  There is another personal experience that builds on this.  And that is the smell of burning gum leaves.  In the past, and still today, whenever a small fire was lit ‘to boil the billy’, the fragrance of the fire was associated with friendship, convivial tea-drinking, and conversation.  Dried gum leaves were the perfect one-match fire starter.  The smell of burning gum leaves is pleasant, readily recognised, and soon becomes a deeply held memory.

“The families back home heard and understood this and sent gum leaves with their letters to those at the front.  Nurses wore gum leaves pinned to their capes.  Soldiers sometimes burned the leaves in small piles at the front line so the smell would drift along the trenches and others could be reminded of their country’s distinctive smell.

The smell of Eucalyptus is the smell of home.”