17 February 2008
Otherwise known as grey gum. There are so many trees given this name on the east coast of Australia, because there are rather a lot of grey gums. About ½ dozen are members of the Grey Gum Group - rather obviously named for their grey bark. All members of the group are prized for the strength and durability of their timber, and in the early days of European settlement were heavily logged for use in construction.
The tree can appear to be a small mallee in tougher sites where the soil doesn’t quite suit, but on the Central Coast we generally see a beautiful tall, elegant tree, 35 m or so high, with a tall, straight cylindrical trunk.
The bark sheds to the ground, there is no collar.
Some people complain about the mess that gum trees leave in their gardens. It is true that they shed huge quantities of bark, but only once a year, and it makes wonderful kindling, is a good weed suppressant, and most importantly, makes a home for uncountable creatures as it breaks down and becomes soil. They can grow to be very large tree so are not really suited for today’s smaller gardens in any case. Whilst we hang on to our remnant bushland you can enjoy them that way, interspersed with other beautiful gums.
The name, grey gum, is a dead give away in what to look out for in the tree, but at this time of the year they can surprise.
Most of the time they are a rather uniform, granular surfaced, mottled grey, but once a year the bark is shed in huge slabs and displays new colours, ranging from pale cream to light orange.
Then, more occasionally, when the rainfall has been heavy over spring and summer, the same process is carried out - but this time displaying a most vivid orange trunk.
This year, 2008, the grey gums are spectacular. Tall streaks of bright orange can be seen glowing through the rich greens of the bush. It really is a spectacular sight for a month or two.
The last time I saw them this good was in 2001, also following a few months with a lot of rain. In the afternoon light after a wet day they are just fabulous. I want to use words, like stupendous, gorgeous, fantastic, mind boggling, etc. It’s the only way to try and get across just how wonderful these trees are.
Once the new bark weathers the colour fades to a light grey then weathers a little more until the medium grey is back for the rest of the year. The magic comes to an end.
Like most of the eucalypts on the East coast they have broad lanceloate leaves, 14cm x about 3.5cms. The leaves are discolorous, glossy, green above and lighter below.
The many chewed holes in the leaves attest to the fact that they are enjoyed by wild life.
The bark is often covered in scratches too which I suspect are made by goannas as they patrol the trees looking for food, birds nests for example.
The trees are also a food source for koalas so I suppose there is a chance the scratches are their doing. I have never seen a koala in the wild in my neighbourhood, but I have heard them calling during mating season so that remains a possibility.
Lastly the flowers. Like all east coast gums they are white. In the case of this particular grey gum they are also sparse and held generally high in the canopy and so the searcher doesn’t often see them with the naked eye. It is surprising how easy it is for small white flowers to blend in with canopy and the sky as you search both.
The buds are held in groups of 7 to 15 and are pointy. There is a scar across where the bud top will fall away to expose the flower. They flower January to March.
The following fruit hang on the tree for quite a while. They are small, round and with a cross in the top, rather like a small round hot cross bun