Diazanon
mjc (ASMJC@ASUACAD.BITNET)
Wed, 19 Dec 90 11:40:39 MST
Over the summer I had a very bad scale problem on my Sarracenias. Some
of the scale spread out onto Drosera (binata, intermedia) and Utricularia
species.
I finally decided to resort to chemical warfare. By suggestion from
Gordon Snelling, I mixed up some Diazanon. It is mixed in water and
applied as a spray. I gave my Sarracenias about 7 applications over
about two weeks. It has been roughly a month since the last treatment.
The results are very good. The scale dried up and flaked off. I have
seen no new scale on those plants that recieved the full treatment.
(Some plants which got only a casual spraying or two are still suspect).
Importantly, I saw no toxic effects on any of the plants! (Barry, that
Drosophyllum which you though twas effected was not. It is still alive
and well.) I did not treat the utric sp because it is so much easier to
rip out some underground stolons and regrow the thing; discarding (or
experimenting outdoors) with the infected portions. All the infected
plants were going dormant at the time, and this may have sped the
scale's dissapearence. It is yet to be seen what will come back from
eggs or reinfection once growth resumes, but I am happy enuf with
Diazanon to try it again if that happens.
Diazanon appears to be a contact poison only; not a systemic If you
don't hit the bugs they will probably live. I am also toying with an
other way to remove scale from those troublesome Sarracenia rhizomes.
If the plant is submerged in water for a week (preferably longer) this
usually kills scale, and would probalby bother mealybugs too. Attempts
at submerging entire plants had some bad effects (rotting of leaves), it
looks like it is best to leave a few leaves sticking out of water.
Someone wrote that S. psittacenia is best overwintered submerged (as in
habitat) and this one probably would take full submergence. It looks
like a good way to deal with those rhizomes, and it doesn't rrequire
insecticides either.
MJC