Tuesday, July 7, 2009

Hoop Pine Babies

Araucaria cunninghamii
Hoop pines can have thousands of these babies, scattered under the trees, looking like little green dragonflies. (Double click for s closer look.) There is a great crop of them in the Boyce garden at present.
They won’t grow, these seedlings, because the roots of the parent trees exude a substance which eventually kills them off. Biochemical inhibition, it’s called.
Flindersia species (such as crows ash, Flindersia australis) can do the same thing to hoop pine seedlings. Crows ashes like to be the tallest trees in their own neighbourhood, and can prevent themselves from being shaded out by any too-close hoops. So, unfortunately, can those feral pines which escape from our forestry plantings or from private gardens. In this case, however, it is the introduced pines which are the aggressive colonists, preventing hoop pines from reproducing in what was once their own territory.
Allan Cunningham, after whom the trees are named, never did get to the site where Toowoomba now stands - but he saw it from a distant vantage point somewhere near Grantham, long before any white person reached it . He was quite excited to see his newly discovered Araucaria dominating the skyline. It must have looked something like this view at Canungra.

The Boyce Garden (corner of Range and Mackenzie Streets, Toowoomba) is the last tiny remnant of the rainforest he saw, and even its hoop pines were planted in the 20th century. It’s amazing how thoroughly we ex-Europeans have managed to exterminate whole environments, since our ancestors first settled in Australia.


Piers said...

Can the Hoop Pine babies be taken out of the ground and planted elsewhere?

Patricia Gardner said...

Hello Piers.
If you have young tree seedlings, it can be possible to transplant them if it is done with great care.
The risk is that the root interference will give you an inferior plant. I might be weaker, and more likely to fall over years later when it is a big tree.
For success, it is important to transplant the seedlings when they are VERY YOUNG. You will find that even seedlings as small as those in the photo will already have a root three or four times as deep as the plant is tall. This applies to any dry rainforest tree species.
It is very important not to break even the tiniest part of the roots at the tip.
The best approach is to make sure the ground is very well watered before you remove the seedling. To get the water to soak well down may take several days, but it is worth the effort.
Replanting should also be done with plenty of water, so that the tiny hair roots don't dry out because of coming into contact with dry soil. Make sure the hole is deep enough and wide enough for the root tip to point downwards, then fill it carefully. You don't want the root to bend up in J-shape.
Be very gently with firming the soil so that small roots don't break off.
Best of luck!