On 01/09/2011 16:28, Jeff Layman wrote:
Anyone know if the eggs of these can remain dormant for many months? I
understand that the adults can overwinter, but what about the eggs?

I reckon they can too. It is surprisingly difficult to be rid of them if
you have anything that can act as a serious host. Growing something
sacrificial as an indicator plant and maintain eternal vigilance is the
only way. In a greenhouse you can try the predator mite and in a warm
summer (not this one) it will do some good but indoors it doesn't work.

I have a plant (Brighamia insignis) which is kept in a bay window with
several other plants. Every year, at this time, it gets a heavy
infestation of RSM. None of the other plants are affected. A spray of
thiamethoxam and abamectin seems to kill off the mites (although not
before they've done a lot of damage). I repeat the spraying after 2 or 3
weeks to kill off any which have hatched from the eggs already laid at
the time of the first spraying.

If they still do them Phostrogen did a plant pin that worked OK as an
anti red spider mite treatment on a fire and forget basis for most of a
season.

This year I thought I saw a bit of a web a few weeks ago, but it didn't
seem to spread. At no other time of the year, or in previous years, have
I seen RSM on these or any other plants, and the window has not been
opened, so where are they coming from?

Eggs in tiny nooks and crannies. You have to hit them every two weeks
for ages to get every last one. I suspect they have staggered maturity
or something. Certainly the eggs will survive sprays and smokes.

Regards,
Martin Brown