Its about 20 years old, and has been (until now) producing bountiful supplies of manderine.
Nothing has been applied to the tree to suggest a cause for this.

Could anyone provide some suggestions as to why it is?




http://img228.imageshack.us/i/p1060727b.jpg

Welcome to The Citrus Growers Forum, we are pleased to have you as a member. You will find several members on this forum from New Zealand. Looking at the picture, your tree looks to have a bad insect infestation. The black growth on the leaves is called Sooty Mold. Sooty Mold is a mold that grows on the excrement from various insects, such as aphids, white fly, scale, mealy bug and etc. Your tree needs to be sprayed, and sprayed rather quickly. - Millet (780-)

Millet is correct in that sooty mold is a sign of insects feeding, but I am sure Millet would agree that the insects may be long gone at this point. I would determine if the insects are still present before spraying.


Ned