North American Fruit Explorers mailing list at ibiblio

[sherwin dubren <sherwindu@comcast.net>]

We have been spraying our fruit trees for over 20 years, but this year
there is more residue at the bottom of our 2 gallon tank than we can
remember.  Our mixture has usually been wettable powder Imidan and
Captan.  We also add a sticker.  This year we introduced a calcium
liquod, which is reported as compatible with other chemicals.  What
we are seeing is a light brown sludge, about a half cup, at the bottom
of the tank after using up the spray liquid.

My concerns are twofold.  Firstly, that this problem is contributing
to the problem of clogging up the spray nozzle, although we can
usually go through one full tank before it needs a cleaning.

The second concern is what exactly is precipitating out of the
spray solution.  If it is one or more of the chemicals, does that
mean that the full dose of chemicals is not making out the nozzle?

We occasionally alternate our sprays with a general orchard spray
from Bonide, and that doesn't seem to have this problem.  The
chemicals are measured out carefully and hopefully accurately.
We have mostly apple trees, but some peaches, plums, apricots,
and sour cherries.

Any thoughts on this?

                         Sherwin in zone 5