[aroid-l] Alocasia robusta & macrorrhizos Borneo Giant
- Subject: [aroid-l] Alocasia robusta & macrorrhizos Borneo Giant
- From: "Peter Boyce" email@example.com
- Date: Sun, 16 Nov 2003 14:59:41 +0700
I've been having a very interesting email correspondence regarding A. macrorrhizos Borneo Giant vs. A. robusta and it seems that there are different plants circulating under the name 'Borneo Giant'.
For what they're worth here are some observations of A. robusta here in Borneo.
The juvenile stage of A. robusta has a rather smooth leaf with the veins on the undesurface not particularly prominent and it can look VERY different to mature plants (not just the size difference!) It is only when the plant begins to mature (c. 1 m or more tall) that the very pronounced veining on the lower leaf surface becomes prominent.
There are two ways of distinguishing A. robusta even as a young plant. One is that the undersurface of the leaf is coated with easily removed white powdery wax. The other is that cut tissue turns orange immediately on exposure to air.
Mature A. robusta are very easily distinguished from A. macrorrhizos by the way that the inflorescences appear. In A. robusta a large cluster of spathes, up to 40, is grouped in the centre of the plant; A. macrorrhizos produces inflorescences in twos or rarely threes at the base of each leaf. The lower spathe (the tubular part) is white with conspicuous red markings in A. robusta, it is pale green and un-marked in A. macrorrhizos.
Hope this helps some