Broad mites (I think), anyone ever dealt with these?

[Orchid-fever]

I have had a pest decimating my collection of orchids. I tried repotting because I thought it may have been a bad batch of coconut husk chips. I have sprayed acephate and malation, azadiractin, and now Talstar (bifenthrin…a synthetic pyrethroid) multiple times over the last 9 months and still my leaves brown from the bottom and die. Also the color of the leaves is lighter than it should be. I have dealt with other pests and never had a problem. The broad mites are only seen under 40 x magnifications. They are transparent clear to brown and look like a white dotting on the underside of the leaves. There seems to be some leaf cell collapse in brachys. I am at my wits end. Any suggestions? I’ll post photos soon. HELP!

 

[luvsorchids]

When you say multiple times spraying, were you doing it on a regular, consistent basis? Most pests require spraying about once a week for a minimum of 4 weeks. Did the pests go away and then come back when you sprayed?

Susan

 

[Orchid-fever]

Most sprayings were 2 to 4 weeks apart, however acephate was used often and is systemic so it should have been absorbed into the tissue of the plant. I have been spraying more often as of late but still not more than biweekly.

 

[Ross]

If you're convinced that the problem is Broad mites, check out these web pages. http://www.entomology.umn.edu/cues/inter/inmine/Mitesb.html
http://entomology.ifas.ufl.edu/creatures/orn/broad_mite.htm

 

[SlipperKing]

Do you have conformation of these mites? You know for sure they are there? Because what you first discribed sounds very familar to what I experience a number of years ago. It wasn't an infestation at all but a nutritional issue. Excessive loss of older leaves, yellow/pale green in color and root tip burn. Sunken brown areas in all genera. I had moved about a mile down the road but to a neighboring town. To my shock, I discovered the town I moved from was on surface water and the town I moved to was on well water! I started collecting rain water and everything went back to "normal"

 

[SlipperKing]

According to Ross's references there are only two miticides, Avid and Quali-Pro that work aganist broad mites.

 

[Orchid-fever]

I have thought about the possibility that my water is to blame. I have checked the PPM and it is about 50 ppm out of the hose. It is municipal city water & I do let the chlorine evaporate before I use it. That being said the problem only presented itself since we moved to our current house 2 years ago. (Only .5 mile from where my orchids grew like weeds.) I have not had the Broad mites confirmed by an agricultural extension or anything but I have use 40-100x microscopes and can see them clearly. Small...very small translucent clear to brown mites with the "dotted" egg sacks. Maybe they are some kind of dust mite but I really believe them to be Broad Mites. I am thinking about resorting to AVID but I have a 9 month old son and my orchids grow in a room attached to the main house.... not really the best situation chemical around a baby.

 

[Ross]

How many plants do you have? The U of M website has this non toxic solution: "Cultural control: Broad mites are very sensitive to heat. Lowering infested plants into water held at 43 to 49°C for 15 minutes will destroy broad mites without damaging the plants." For americans, that's 110 to 120F.

 

[likespaphs]

...Most pests require spraying about once a week for a minimum of 4 weeks.....

um, this isn't quite correct.
the label is federal law and should state after how long it may be reapplied. it may be listed in the area dealing with resistance management or possibly under the general info section. pesticide resistance will happen, but one tries to delay this by rotating pesticides.

if you are rotating pesticides, then it is at the discretion of the person applying the pesticides to determine when to apply the next pesticide in the rotation after assessing if the plants seem strong enough, etc.


edit: i didn't mean to say you're wrong, though, as some pesticides require treatment once a week for several weeks. others applied that frequently will result in damage or death of the plant. four times in a row is a lot without rotating, though......

 

[NYEric]

Lowering infested plants into water held at 43 to 49°C for 15 minutes will destroy broad mites without damaging the plants." For americans, that's 110 to 120F.

After blanching, chill and serve w/ hollandaise! :evil:

 

[Jim Toomey]

Read up on Neem oil.
Several companies package it.

Neem oil can be used as a suffocant (spelling?)... it clogs up their breathing pores.
They suffocate to death.

They do not build up resistance to suffocating.

Reapply in 5-7 days to kill of the latest hatchlings.

In many cultures they drink Neem oil and apply Neem oil to their skin.
Read: harmless, and may even be good for you!
No need for the rubber gloves or respirators.

Bill Thoms of Bulbo fame uses it with great results.

Must be applied/sprayed when plants are cool.

It must be used when cool, so maybe one evening after the little one goes to bed.

You need to use about 1/2 to 1 teaspoon of Ivory liquid dish soap per gallon of warm water,
to help emulsify the mixture.
It should be a yellow milky color when mixed right. Keep it mixed up as you use (just shake the container once in awhile).

As with any chemical and when you spray an unfamiliar product, only spray a few test subjects first and see how they react. Test a range of different species/hybrids.

Then if everything is fine, then you will have confidence that it will not damage anything.

Again, apply when everything is cool and will be staying cool. Evening is best.

Did I mention to only spray when cool?

Good luck and kill those *******!
Jim T

 

[goldenrose]

:sob: Whoa ........
brachys are sensitive to Neem, I don't recommend it!

 

[NYEric]

I wonder why?

 

[goldenrose]

Can't tell you why but I bet someone on this forum can!
This is my experience, is it just coincidence? or ......
I purchased 3 thailand niveums from Paphiness 2 years ago. This was the first year they bloomed & all had at least one horn on the pouch. I have a Clairette (Sierra Bell x concolor) from OL that I purchased a couple of years ago in bud. When it bloomed out, no horns. This year it had a horn. My leucochilum from Tom K. had a small horn too, it hasn't in the past. I mentioned this to Tom K., what am I doing with my culture that might cause it? The first thing he asked was if I used Neem oil. I use it occassionally, maybe twice this year. Koopowitz's book 'Tropical Slipper Orchids' page 362-3 gives cultural hints to succeed with brachys & one of them is "Do not use oil-based phytochemicals on brachys, oil often induces severe dieback & rot in the leaves. Always test new chemicals on an experimental plant & examine it for a week to 10 days before making wholesale applications of the new agent. Paph.bellatulum seems to be more sensitive than the other species."
Decathlon & Enstar II were the only other chemicals used, so I can eliminate all chemicals on the brachys or eliminate one at a time & see what happens. Seeing they only bloom once a year, I'm going to try to eliminate all chemicals. Tom did say he uses the Bayer product that Hausermann's sells & has had no problems.

 

[Jim Toomey]

Interesting...
At slipper symposium, we were talking about pesticides during a round table style Q & A.

Now this is anecdotal with no scientific research, but they were all experienced growers:

Several members mentioned (2-3 people in a crowd of 60) that they had used the Bayer 3 in 1 product (the one with out the fertilizer added), they said that when they used the 3-1 (and that was the only one they used) many of their flowers were deformed the next blooming. They stopped using it and the problem resolved itself the following year/blooming.

There are many factors that could cause extra tissue and other deformities, it could be a coincidence that they all tried it and had problems. But those people wont be using it again...

I have used Safari (an excellent systemic) with very good effect and no deformities (so far).

As far as the Neem oil goes, yes plant can burn if sprayed on warm plants or if the sprayed plants heat up...

The major caveat is spray when is cool and will stay cool until it dries.

But like you said about the brachys, if in doubt, do not use it and always, always test first!

A soapy water spray just by itself, will also help rid your plants of mites as well.
Best of luck!