In article , Rodger Whitlock
writes

Any evidence of ants farming the aphids? Take a hard look at the
trunk and if you see ants scurrying up and down, consider that
sufficient evidence.

Well if I get a chance to stand under the tree with wasps flying about
I'll certainly look! We have a wasp man coming this afternoon if it
doesn't rain, to eliminate two nets on the front of the house.
That may have some effect also.



If ants are involved, then if you can keep them out of the crown
of the tree the aphid problem should decline and fall. Some kind
of barrier around the trunk would be called for. The sticky bands
used for wintermoth control will work, but if you can get Sevin
(carbaryl) and spray a band, say, 18" wide around the trunk and
renew it every two or three weeks, that will suffice.

Ants are loath to cross a band of sevin -- they taste it with
their feet -- and if they do, they die.


Right, I'll go and see if I can buy the stuff, never heard of it till
you said Rodger.

If ants aren't involved, then painting the trunk with Cygon
(again, if you can still get it) might control the aphids.


Unfortunately, effective special-purpose insecticides such as
Sevin and Cygon are nearly impossible to obtain any more. The
greens have completely driven them off the market, and the
pyrethrins that are left simply won't work in the same way.


Are they systemic then? I thought systemic needed to go onto leaves so
that the liquid went onto the surfaces that would absorb the chemicals
and take it into the sap. Does the trunk of a tree absorb stuff?

janet
--
Janet Tweedy
Dalmatian Telegraph
http://www.lancedal.demon.co.uk