One day, at bushcare with the Wentworth Falls Lake Bushcare Group, Ross Day called me over to identify a strange plant. It was like nothing we had seen before, five close vertical stems with enormous trifoliolate leaves springing directly from them on long petioles. Those leaves were dark green, only about 25 mm wide, but anything up to 400 mm long. And tough! They were also armed with vicious teeth along the margins.
It was identified by staff at the Herbarium in Sydney as the New Zealand Lancewood, Pseudopanax crassifolius, in the family Araliaceae. (It has a relative in SW Tasmania called Pseudopanax gunnii, and both are related to our Elderberry panax, Polyscias sambucifolia).
The intriguing ecology of this plant involves a straight upright trunk with largely inedible leaves. All this is designed to deter being eaten by the NZ Southern Giant Moa, a flightless bird 3 m high. Of course the Maoris killed the last one hundreds of years ago, but in evolutionary terms the tree hasn’t caught up yet! Even more amazing is that after 15-20 years, when the tree gets to about 5 m, well out of the range of the Giant Moa, it changes abruptly to produce broad succulent leaves in a short canopy, and then flowers more or less normally.
Don’t ask me how it got to Wentworth Falls! We surmise that it was a garden plant that was no longer required, dug up, and thrown in the bush to die. It didn’t, but put down roots in the damp leaf litter and survived. I suspect that it was lying down at the time, and that the present five trunks sprouted like epicormic regrowth from that trunk.
David Coleby, Wentworth Falls Lake Bushcare Group, firstname.lastname@example.org