permaculture

[jedd <jedd@progsoc.org>]

On Sun, 13 May 2007, paul wheaton wrote:
> A plum tree I recently started caring for has lost about a third of
> its leaves to aphids this year.   Every time I buy ladybugs, they just
> fly away - and this time was no different.  I released them at dusk
> and they were all over the tree when it was dark. In the morning they
> were all gone.   Maybe they ate some aphids at night before they left.

 Some may have stayed, surely?  Worst case they're likely to have
 gone off about as far as they could fly - this bodes well, as by
 definition it's about the same distance as they (or their progeny)
 can fly back in this, or in subsequent, seasons.

 Note that aphids are sometimes protected by ants -- you may need
 a double-pronged attack against aphids in a tree, which is happily
 far easier to orchestrate than aphids in, say, a sage bush near the
 ground.  You get those strips that sit around the trunk, or the
 little half-cylinder ring that you fill with water and that you caulk
 up (so ants can't slip inside it).

 My understanding is that in the absence of ants, aphids can't
 stand up to much of an attack from predator insects.

> I've sprayed the tree twice with alaska fish fertilizer (as a foliar).
>  I think this is a quick step in helping the tree become stronger and
> fight off the aphids naturally.  I've now mulched the tree and started
> planting things that might help the tree in the long run.

 Garlic/chilli sprays may work, but I think a weak soap solution is
 meant to be pretty effective.  Is white oil indicated with aphids?
 I think I used that once or twice but in my climate, when aphids
 are active it's usually too warm to put suntan oil on my trees.

 Jedd.