Argyrodendron trifoliolatum

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Argyrodendron trifoliolatumFamily: Malvaceae
Genus: Argyrodendron
Common names: White booyong, Brown tulip oak
ALA reference

Seeds from this tree germinated in November 2008 following the fierce storm that flattened The Gap. Now 31⁄3 years later we still have about 50 seedlings that are mostly about 80 cm to a metre in height scattered within a 20 metre radius of the parent tree. But there is a marked difference between the smallest and tallest plant. The plant in the photo is over 2 metres in height while others are only 7 cm despite being exactly the same age (give or take a day or two). This shows just how difficult it can be to estimate the age of a tree. (March 2012)

In my notes last month I stated that many of the seeds from this tree had germinated and started to send down a root. We now have dozens of little seedlings. This is really a momentous event in the life of this tree. I estimate that it must be at least 80 years old but has possibly been growing for well over 100 years. However I don’t believe that there is another tree of this species within kilometres. It is possible that there were others in the Reserve that were killed by the cat’s claw however I can find no evidence of this. This then may be the first time that the tree has successfully reproduced! Whether this is the result of serendipitous weather conditions at the time the tree shed its seeds, or the fact that the weeds have been cleared from around it, or a combination of both, I don’t know. However the seeds are known to have a very short period of viability and must be planted as soon as they fall if they are to germinate successfully. I just hope now that some of these little seedlings survive and thrive. (December 2008)

The tree that was covered in flowers in August is now bearing a huge crop of seeds. From the distance it almost looks as if the tree is covered in fawn coloured flowers. The seeds are in the form of a samara which has a dry fibrous papery wing attached to the dry seed. As the seeds drop, this wing allows the seeds to whirligig slowly to the ground so facilitating dispersal on windy days. The seeds are about 5 – 7 mm across and the wing about 30 mm long. The seeds are a popular food of the brush turkeys so they are in for a real feast! I have been staggered by how quickly the fallen seeds have germinated. In just one week, assisted by the recent rains, the seeds have split and are starting to send down a root. (November 2008)

Argyrodendron trifoliolatumThis is a large emergent rainforest tree attaining a height of over 40 metres, with a prominent buttress. This specimen is an old tree and clearly part of the remnant vegetation. While it is common in rainforests I am aware of only one other tree in our neighbourhood and that is at the other end of Cliveden Avenue on the bank of Oxley Creek. The plant derives its name from argyros – silver and dendron – a tree; alluding to the silver sheen on the underside of the leaves, and trifoliolatum for the three leaflets that make up each leaf.

This is the first time the tree has bloomed for a number of years and is now smothered in flowers. I’m hoping it will set some seeds which are about 8mm in diameter with a papery wing about 30mm long. The tree is full of Kurrajong mistletoe (Notothixos cornifolius) which is visible in the photograph as the dark green patches. The tree also supports two large creepers – Jasminum simplicifolium subsp. australiense and Trophis scandens. (August 2008)