J. Del Col wrote:

"wendy7" wrote in message news:v7D1d.38200$9Y5.24489@fed1read02...


I heard that Kelthane works! Especially made for spidermites.
Male & female flowers? I would be happy with either!*G*




Kelthane should --not-- be used indoors.


I second that... Smells terrible too, plus I don't think you can
buy it anymore, anyway. Avid (abimectin) is supposed to be good,
although maybe not indoors. Dormant (horticultural) oil is good too,
and puts a nice shine on your leaves. I'd start with the oil and work my
way up. Speaking of random pesticide information, I stumbled across
this website http://www.plantprod.com/catalogue/1...ecticides.html

You can put a serious dent in your spidermite population by hosing
down the foliage once a week or so (use a lot of water, and concentrate
on the back of the leaves), and getting your humidity up, way up. 80%
is a good target.

Some other options that don't involve pesticides - predatory
insects. Here is the first one I came across with google:
http://www.sgs-hydroponic.com/produc...ls.php?id=1250 (I've done
business with SGS many times, and they are good)
Green Lacewings supposedly eat spidermites, and there are at least half
a dozen species available for mite control. Some have the added
advantage of eating other pests (like mealybugs or aphids).

I'm still learning to cope with the little buggers, since I love
catasetums and cycnoches. I have to pick the ones that the mites like
too... You'd think I'd be smarter than little insects, but no, not me.

Rob

--
Rob's Rules: http://www.msu.edu/~halgren
1) There is always room for one more orchid
2) There is always room for two more orchids
2a. See rule 1
3) When one has insufficient credit to purchase
more orchids, obtain more credit
LittlefrogFarm is open - e-mail me for a list )

J. Del Col wrote:

"wendy7" wrote in message news:v7D1d.38200$9Y5.24489@fed1read02...


I heard that Kelthane works! Especially made for spidermites.
Male & female flowers? I would be happy with either!*G*




Kelthane should --not-- be used indoors.


I second that... Smells terrible too, plus I don't think you can
buy it anymore, anyway. Avid (abimectin) is supposed to be good,
although maybe not indoors. Dormant (horticultural) oil is good too,
and puts a nice shine on your leaves. I'd start with the oil and work my
way up. Speaking of random pesticide information, I stumbled across
this website http://www.plantprod.com/catalogue/1...ecticides.html

You can put a serious dent in your spidermite population by hosing
down the foliage once a week or so (use a lot of water, and concentrate
on the back of the leaves), and getting your humidity up, way up. 80%
is a good target.

Some other options that don't involve pesticides - predatory
insects. Here is the first one I came across with google:
http://www.sgs-hydroponic.com/produc...ls.php?id=1250 (I've done
business with SGS many times, and they are good)
Green Lacewings supposedly eat spidermites, and there are at least half
a dozen species available for mite control. Some have the added
advantage of eating other pests (like mealybugs or aphids).

I'm still learning to cope with the little buggers, since I love
catasetums and cycnoches. I have to pick the ones that the mites like
too... You'd think I'd be smarter than little insects, but no, not me.

Rob

--
Rob's Rules: http://www.msu.edu/~halgren
1) There is always room for one more orchid
2) There is always room for two more orchids
2a. See rule 1
3) When one has insufficient credit to purchase
more orchids, obtain more credit
LittlefrogFarm is open - e-mail me for a list )

Predatory insects are ultimately the control in a stable, healthy
greenhouse. While difficult to eliminate a pest with predatory controls,
it helps keep things in balance. It's not unusual for a problem to become
worse as a function of spraying; if the spray is detrimental to predators
as well as the target species, you can wipe out the predators only to see
the pests return with a vengeance.

Of course, for a small greenhouse, this isn't really a concern-
except perhaps for mites. Mites are nasty, perncicious creatures that can
get out of hand when things get seriously out of whack. In many
greenhouses, there are probably low levels of opportunistic controls-
predators at low levels that feast on spider mites. However, most (if not
all) are susceptible to the pesticides employed in getting rid of mites.

This is one reason mites get out of control under certain
conditions (low humidity, high temperatures): the predators are strained,
and don't do well under these conditions. On the other hand, Isobyl
LaCroix notes in her excellent book on African orchids that she's seen
mites thriving on plants that had moisture condensing on them. I've
corresponded with Isobyl, and I'm convinced what happened was that there
simply weren't any predators. However, their introduction under those
conditions would have made for quite the mite slaughter. Further note that
if the environmental conditions are excellent for mites, they're probably
rotten for the predatory controls. Here in the desert, mites (and
whitefly) are constant concerns. Unfortunately, none of the predatory
controls work well under high heat, high light, and low humidity.

The net upshot is that the correct conditions for growing most
tropical epiphytic orchids (good humidity, good air circulation,
appropriate temperatures) and less stress will naturally control pests-
possibly because of the presence of biological controls that do well under
those conditions. "Spray and pray" tempts fate- not that it isn't
occasionally necessary, but if you DO try to kill everything, keep an eye
out for the backlash and try to understand what is happening when it does
occur. Otherwise, you end up in a spiral of spraying, followed by
improvement, followed by reinfestation.

As an aside, there are some very clever systems for controlling
some insects in some crops with predators. For example, it is possible to
keep pots of wheat that are infested with a certain kind of wheat aphid
that does not attack other species of plant. These infestations are
predated upon by a predator whose name escapes me such that good numbers
of predators are always in the greenhouse. As a result, when a few aphids
show up out of the blue to attack the crop of value, they can do so when
numbers are low, making them less likely to explode in numbers.

The downside, of course, is that you need to have heavily infested
wheat plants in your greenhouse, which don't look that good. It's still
cheaper (and more effective) than buying a box of FedEx'ed predatory
insects whenever you need them.

The e-mail address in the header doesn't work. Sorry.

Cheers,

-AJHicks
Chandler, AZ

Predatory insects are ultimately the control in a stable, healthy
greenhouse. While difficult to eliminate a pest with predatory controls,
it helps keep things in balance. It's not unusual for a problem to become
worse as a function of spraying; if the spray is detrimental to predators
as well as the target species, you can wipe out the predators only to see
the pests return with a vengeance.

Of course, for a small greenhouse, this isn't really a concern-
except perhaps for mites. Mites are nasty, perncicious creatures that can
get out of hand when things get seriously out of whack. In many
greenhouses, there are probably low levels of opportunistic controls-
predators at low levels that feast on spider mites. However, most (if not
all) are susceptible to the pesticides employed in getting rid of mites.

This is one reason mites get out of control under certain
conditions (low humidity, high temperatures): the predators are strained,
and don't do well under these conditions. On the other hand, Isobyl
LaCroix notes in her excellent book on African orchids that she's seen
mites thriving on plants that had moisture condensing on them. I've
corresponded with Isobyl, and I'm convinced what happened was that there
simply weren't any predators. However, their introduction under those
conditions would have made for quite the mite slaughter. Further note that
if the environmental conditions are excellent for mites, they're probably
rotten for the predatory controls. Here in the desert, mites (and
whitefly) are constant concerns. Unfortunately, none of the predatory
controls work well under high heat, high light, and low humidity.

The net upshot is that the correct conditions for growing most
tropical epiphytic orchids (good humidity, good air circulation,
appropriate temperatures) and less stress will naturally control pests-
possibly because of the presence of biological controls that do well under
those conditions. "Spray and pray" tempts fate- not that it isn't
occasionally necessary, but if you DO try to kill everything, keep an eye
out for the backlash and try to understand what is happening when it does
occur. Otherwise, you end up in a spiral of spraying, followed by
improvement, followed by reinfestation.

As an aside, there are some very clever systems for controlling
some insects in some crops with predators. For example, it is possible to
keep pots of wheat that are infested with a certain kind of wheat aphid
that does not attack other species of plant. These infestations are
predated upon by a predator whose name escapes me such that good numbers
of predators are always in the greenhouse. As a result, when a few aphids
show up out of the blue to attack the crop of value, they can do so when
numbers are low, making them less likely to explode in numbers.

The downside, of course, is that you need to have heavily infested
wheat plants in your greenhouse, which don't look that good. It's still
cheaper (and more effective) than buying a box of FedEx'ed predatory
insects whenever you need them.

The e-mail address in the header doesn't work. Sorry.

Cheers,

-AJHicks
Chandler, AZ