Australian Xanthorrhoea Notes

These notes were sent to me in 2003 by John Summerfield in Australia.

I grew up on a farm in the south west of Western Australia, near Margaret River (now famous for surf and wine) in the 40s & 50s.

On our farm we had blackboys. At one point Dad owned 750 acres or so in the Scott River, inland and east of Augusta. We had blackboys there too. Thousands of them.

There is a business here in WA that claims considerable success transplanting those (and Zamias). And of course, I've seen their root systems. Jarrahs, Karris and Marries are trees that grow in some of the same places as blackboys, and I've seen a Karri stop a D7 (large truck). Those trees do indeed have decent taproots.

In contrast, I spent some weeks towing a baby giant (cultivator) behind a Fordson Major (40 HP tractor), driving right over blackboys, both dead and alive. They have a mass of fibrous roots quite like the roots on grasses. I never saw a taproot on one.

I will add that the Scott River area where Dad's farm was located was mostly under water (not by much, it's true) for some months in winter, and it didn't seem to bother the blackboys at all. I suspect those were a different species from those near where I live now, where there is a hilltop and clay soil too covered in masses of them, mostly small.

There is no wood in a blackboy, the trunk is a mass of fibre covered with the stumps of dead (most often burnt) leaves, but the base of the trunk is quite hard and can be turned in a wood lathe to make bowls, candlesticks and similar "wooden" items.

And I have seen some that I reckon were at least 20 feet (back when we measured in feet). Those were in coastal sand, within 5 Km or so of the beach: much of the coastal plain (including most of the Perth metropolitan area) is sand, and it's fair to say that area is indeed well-drained (but probably subject to 50 inches or more of rain).

We did have some too, that didn't grow a trunk. The flower stem just had a few flowers at the end, and when dry made a fine spear for small boys to throw around. Xanthorrhoeas are monocotyledons, which are characterised by a mass of roots (like grasses), no tap root (unlike apples and other common fruits), leaves with no central spine (think apples and other common fruit trees), and the number of petals in flowers (but I forget the precise details on that). Of course, a single part (cotyledon) in the seed. I believe they're lilies.

References

• Monocotyledon on dictionary.com provides information on lilies.
• Society for Growing Australian Plants
• Kingsley Dickson of Kings Park in Western Australia. Kingsley was on radio a few days ago talking about growing stuff. He reckons they (at Kings Park) grow blackboys "like onions." So, find yourself some seeds and grow them like onions. Any time of the year.