Spider mites?

Trouble shoot problems you are having with your cactus.
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catlady
Posts: 35
Joined: Fri May 23, 2014 7:05 pm
Location: San Joaquin County, California

Spider mites?

Post by catlady »

I'm posting a lot this weekend, sorry!

I was just checking over my plants and saw a couple of small rusty spots around the spines at the top of my Rebutia krainziana, as well as around some new pups that are just springing up down toward the base. It looks like it might be the early signs of spider mites - no webby-looking fluff, but it does look like the rusty spots I saw when I had an infestation on some rosemary a few years back, as well as the photos under red spider mites in the Pests & Diseases tab above, though not yet as extensive - and considering I've had bug problems with the two other plants I got at the same nursery (a little local one with a tiny cactus section where I will not be shopping again), I wouldn't be surprised. However, I don't have a magnifying glass to really be sure it's a mite problem.

I've sprayed it with a pesticide I had on hand that also treats for mites ( http://www.amazon.com/Schultz-1041-Hous ... roduct_top" onclick="window.open(this.href);return false; ) just in case, and I've separated it from my other plants and put it in a spot where it won't get any direct sunlight for now. I checked all the cacti in that windowsill, and there are no signs of a problem on any of the others.

1. Should I spray everything else with a 1:4 rubbing alcohol and water solution, just in case? Or use the pesticide? If I do the alcohol mist, do I need to move everything out of that windowsill to avoid direct sunlight, and for how long? The pesticide says a couple of weeks, but I imagine alcohol would need less time because of evaporation, right?

2. If it is mites, I'll need to treat the R. krainziana multiple times, right? How frequently and for how long should I treat it? And should I continue treating with the pesticide, or should I switch to the rubbing alcohol/water solution?

3. Is there anything else I need to know or do to keep the mites from spreading/coming back?

Thank you in advance for any advice.

EDIT: Actually, I remembered I'd taken a couple macro photos a few weeks ago when it flowered, and then about a week later when the first two pups got big enough to look like pups (it has three now), so I looked back. No orange when it was flowering on June 30, but a few teeny, tiny orange spots around the pups on July 6, so it's been going about two or three weeks. I'm thinking I should treat the two cacti next to it, and maybe the whole windowsill (eight plants), just in case - or is that wrong? (And should I move the plants and wash down the sill itself, too?)
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Steve Johnson
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Joined: Thu Nov 03, 2011 4:44 am
Location: Los Angeles, CA (Zone 10b)

Re: Spider mites?

Post by Steve Johnson »

catlady wrote:I was just checking over my plants and saw a couple of small rusty spots around the spines at the top of my Rebutia krainziana, as well as around some new pups that are just springing up down toward the base. It looks like it might be the early signs of spider mites - no webby-looking fluff, but it does look like the rusty spots I saw when I had an infestation on some rosemary a few years back, as well as the photos under red spider mites in the Pests & Diseases tab above, though not yet as extensive - and considering I've had bug problems with the two other plants I got at the same nursery (a little local one with a tiny cactus section where I will not be shopping again), I wouldn't be surprised. However, I don't have a magnifying glass to really be sure it's a mite problem.

I've sprayed it with a pesticide I had on hand that also treats for mites ( http://www.amazon.com/Schultz-1041-Hous ... roduct_top" onclick="window.open(this.href);return false; ) just in case, and I've separated it from my other plants and put it in a spot where it won't get any direct sunlight for now. I checked all the cacti in that windowsill, and there are no signs of a problem on any of the others.

1. Should I spray everything else with a 1:4 rubbing alcohol and water solution, just in case? Or use the pesticide? If I do the alcohol mist, do I need to move everything out of that windowsill to avoid direct sunlight, and for how long? The pesticide says a couple of weeks, but I imagine alcohol would need less time because of evaporation, right?

2. If it is mites, I'll need to treat the R. krainziana multiple times, right? How frequently and for how long should I treat it? And should I continue treating with the pesticide, or should I switch to the rubbing alcohol/water solution?

3. Is there anything else I need to know or do to keep the mites from spreading/coming back?

Thank you in advance for any advice.

EDIT: Actually, I remembered I'd taken a couple macro photos a few weeks ago when it flowered, and then about a week later when the first two pups got big enough to look like pups (it has three now), so I looked back. No orange when it was flowering on June 30, but a few teeny, tiny orange spots around the pups on July 6, so it's been going about two or three weeks. I'm thinking I should treat the two cacti next to it, and maybe the whole windowsill (eight plants), just in case - or is that wrong? (And should I move the plants and wash down the sill itself, too?)
Ah, you came to the right place! Could be red spider mites or flat mites, although I think San Joaquin is probably too dry to see flat mite problems. Go with TetraSan -- safe and highly effective as a miticide/ovicide on all plants, not just cacti. You can get it here:

http://www.ebay.com/sch/i.html?_from=R4 ... n&_sacat=0" onclick="window.open(this.href);return false;

Spray everything once, so you won't have to worry about spraying with alcohol all the time. If you're dealing with a heavy infestation, you may need to spray the TetraSan again a month or two after the initial application. Also, TetraSan doesn't have any pest resistance problems, so using it as a preventative is a great idea. I spray all my cacti in early spring and maybe again in mid-summer. Flat mites used to vex the he11 out of me, so if it weren't for TetraSan, I'd still be chasing after problem cacti with IPA spray. By the way -- yes, spray your plants away from direct sunlight.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
catlady
Posts: 35
Joined: Fri May 23, 2014 7:05 pm
Location: San Joaquin County, California

Re: Spider mites?

Post by catlady »

I looked up some of the threads with flat mites, and I could actually see that being the problem. We've had abnormally humid weather up here (70% today) for maybe a month now, and I don't have air conditioning aside from a window unit I only run when it tops 100 (which it hasn't), so indoors is pretty humid, too. And with no webbing, I wasn't sure if it was really spider mites.

I will order the TetraSan and give all my plants a once-over. By spray them away from direct sunlight, do you mean that once it's sprayed, I can return them to the window, or should I keep them out of the sun for a couple of days? And does that also apply to the cactus I sprayed earlier today, or does that need to stay out of the sun for longer? And should I go with the alcohol mixture until the TetraSan arrives? Thank you so much for the advice! And sorry for all the questions — aside from my M. fraileana coming with some resident hungry caterpillars, I haven't had any pests other than the mites and powdery mildew combo that did in my poor, ill-fated rosemary and I'm not really sure how to deal with them.
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Steve Johnson
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Location: Los Angeles, CA (Zone 10b)

Re: Spider mites?

Post by Steve Johnson »

catlady wrote:I looked up some of the threads with flat mites, and I could actually see that being the problem. We've had abnormally humid weather up here (70% today) for maybe a month now, and I don't have air conditioning aside from a window unit I only run when it tops 100 (which it hasn't), so indoors is pretty humid, too. And with no webbing, I wasn't sure if it was really spider mites.

I will order the TetraSan and give all my plants a once-over. By spray them away from direct sunlight, do you mean that once it's sprayed, I can return them to the window, or should I keep them out of the sun for a couple of days? And does that also apply to the cactus I sprayed earlier today, or does that need to stay out of the sun for longer? And should I go with the alcohol mixture until the TetraSan arrives? Thank you so much for the advice! And sorry for all the questions — aside from my M. fraileana coming with some resident hungry caterpillars, I haven't had any pests other than the mites and powdery mildew combo that did in my poor, ill-fated rosemary and I'm not really sure how to deal with them.
Always happy to help! You'll be diluting the TetraSan granules in water, so once the water is dried off after you spray, the plants can go right back out. By the way -- 1/4-1/2 tsp. per gallon. Alcohol spray before you get the TetraSan should be fine.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
catlady
Posts: 35
Joined: Fri May 23, 2014 7:05 pm
Location: San Joaquin County, California

Re: Spider mites?

Post by catlady »

Thank you so much! And thanks for being patient with all of my questions. Luckily I don't think they've spread and they haven't done much damage yet on the R. krainziana (the white spines made the orange stand out really clearly once they got to the visible areas), but I am grateful there's something out there that can hopefully prevent any more problems like this.
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RichR
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Location: Austin, TX / Zone 8b
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Re: Spider mites?

Post by RichR »

How safe and how effective is TetraSan compared to imidacloprid? Imidacloprid is now being cited as a possible contributor to Colony Collapse Disorder (honey bees). I have had mite problems off and on for a couple of years now and I don't know what to treat them with. Are Neem Oil and other "organic" treatments a waste of time?
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jp29
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Location: Tucson, Arizona

Re: Spider mites?

Post by jp29 »

Here are two good reference resources:

http://www.gardeningknowhow.com/plant-p ... -mites.htm" onclick="window.open(this.href);return false;

http://www.wikihow.com/Get-Rid-of-Red-S ... rganically" onclick="window.open(this.href);return false;
James
My cactus cultivation pages:
https://jp29.org/cactuscult.htm Image
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Steve Johnson
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Re: Spider mites?

Post by Steve Johnson »

RichR wrote:How safe and how effective is TetraSan compared to imidacloprid? Imidacloprid is now being cited as a possible contributor to Colony Collapse Disorder (honey bees). I have had mite problems off and on for a couple of years now and I don't know what to treat them with. Are Neem Oil and other "organic" treatments a waste of time?
Neonicotinoids such as Imidacloprid have been blamed for CCD because they scramble the bees' brains. Imidacloprid is useless on pest mites, but TetraSan is highly effective. And since the product contains zero neonicotinoid, it won't bother honey bees or any of the other beneficial insects we'd like to have in our gardens. By the way, orchid growers have been using TetraSan for years. If it weren't for A. Dean Stock's willingness to share his crossover experience growing orchids and cacti, I doubt that any of us would've even known about TetraSan.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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jp29
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Re: Spider mites?

Post by jp29 »

For further reading relating to miticides - Avid, Floramite, Tetrasan, Pylon, Vendex - go to:

http://hyg.ipm.illinois.edu/pastpest/200417g.html" onclick="window.open(this.href);return false;
James
My cactus cultivation pages:
https://jp29.org/cactuscult.htm Image
iann
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Re: Spider mites?

Post by iann »

Identify the mite before spraying anything. Then try a poison labelled for that type of mite first. If it isn't on the label then it may or may not be effective. Tetrasan is only labelled for Spider mites, specifically not for flat mites. If at first you don't succeed, try something else because resistance is widespread. If at first you succeed, try something else next time because resistance is rapid. If labelled products don't work, you can try products that don't list your pest. Very often they simply haven't been tested against it.

Avid (Abamectin) is usually the first port of call for flat mites because it is easy to obtain, quick-acting on a wide range of mites, and long-lasting. Also bear in mind that Tetrasan does not kill adult mites and so will be very slow to have an effect on the relatively long-lived flat mites. For the same reason it is not recommended as the first attack on established outbreaks. Sanmite and Forbid/Judo are also labelled for flat mites, don't know if you can obtain them. Apparently also Mavrik, has a very wide toxicity in including insects.

Don't assume that any poison is safe for bees or other beneficials. Don't spray on blooming plants. As it happens, Tetrasan has relatively low toxicity to bees, but you didn't know that and relatively low toxicity doesn't mean they can go swimming in it.
--ian
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RichR
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Re: Spider mites?

Post by RichR »

Thanks for all the input. I supposed I need to figure out what kind of mites I have.
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