gardener wrote:

I have a large ash tree (in the UK) - it appears to have started to
drop sticky deposits that look just like granular sugar. Problem is
it's all over the patio, and gets picked up on shoes etc, as well as
making the furniture sticky.

It's never done this before - does anyone know what causes it, and /or
how long it lasts for???

Several years ago, southern California was infested with an ash
whitefly. Not only did they drip their sweet excretions on the
ground under the trees, but the droplets were picked up by the wind
as they fell. Those airborne droplets would blow right through
window screens and leave a sticky mess on floors and furniture.

Besides making a mess, the ash whitefly was defoliating large
trees, weakening them and making them susceptible to other insect
damage. Finally, a parasitic wasp that feeds on the whitefly was
found. These were released throughout southern California. Less
than two years later, the problem was resolved.

Since the ash whitefly also causes serious damage to various food
crops, you might check with local agricultural agencies to see if
it is a problem in your area.

--

David E. Ross
http://www.rossde.com/

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