On Sat, 16 Dec 2006 17:07:15 +1100, jils wrote:

there's a tallish (15ft, maybe less), old Schefflera Amate umbrella tree
in my garden in sydney.

just recently, every growth tip has turned black, and leaves are
dropping. there's no obvious pest infestation, nothing has been put on
the soil, nothing's been done any different to the treatment it's had in
the last 20 years. but it's dying!

can anyone shed any light on the problem?

Lack of water.