Dangerously seductive White Cedar

Everyone knows the White Cedar. I forgot once, when asked on radio about deciduous Australian trees. I replied with confidence that the Deciduous Beech, Nothofagus gunnii, was our only winter deciduous plant, with a few odds and ends in the tropics losing leaves at various times in response to drys and wets. Or something like that.

I was reminded after the interview of Melia azedarach, from the eastern flanks of New South Wales up into northern Australia and through to India, China and Japan. And now established beyond this range in Australia and elsewhere, as well as a popular and hardy street tree. (There is one species of Melia only in the Asian region, with one other from tropical Africa.)

The White Cedar does indeed loose its leaves in winter. That when you usually notice the woody fruits, dangling from bare branches or, to the irritation of those who mow lawns, embedded within the turf.

On a Sunday afternoon way back in early November, I took a closer look at the flowers. I knew they were white with a purple splodge but hadn't taken a close look at their inner workings.

That splodge turns out to be an anther [or staminal] tube, which is tube made from the fused stalks (filaments) of the male parts of the flower. The pollen-bearing anthers are attached just inside that minutely toothed top of the tube.

Deeper inside that tube is the female part of the flower, as you can see in this next dissected flower. The ovaries are in the swollen base of that green tube and the receptive stigma at its top, just about where the anthers are sitting.

All very neat and with the pollination action at the top of the tube. It's possible there is something attractive like nectar inside the tube but perhaps the flower is simply protruding its important bits above the flower for the ease of flying pollinators.

My flowers were crawling with thrips of some kind (you can see them on the undissected flower above); or at least the thrips were crawling around the flowers, and then onto my desk at home. I doubt these are effective pollinators, and hummingbirds have been implicated outside Australia. The fruits form pretty readily so I expect they may be self-fertile (the receptive bits are certainly close together!).

Apart from their deciduousness, they are also well know as a poisonous plant. In the Western Australian flora on-line, Florabase, you'll read that 6-9 fruits, 30-40 seeds or 400 grams of bark - take your choice of poison - is toxic.

The message is clearly to avoid consuming any part of this tree. You might also avoid mowing your lawn if there are White Cedar fruits about. As tree expert Greg Moore wrote in The Conversation last year, the fruits are 'as hard as ball bearings' and will fire like bullets. As Greg puts it, this is a hazard for people walking by at the time and, if the fruits land on a path, for others who may slip on them later.

There are non-fruiting forms now available but these have not reached the streets of Glen Iris yet. Still the trees I photographed in November were pretty in fresh leaf, flower and persisting fruit. Better still they weren't growing on my nature strip.