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Chilli thrips in San Antonio ...

Posted by roselee z8 SW Texas (My Page) on
Sat, Oct 6, 12 at 18:43

I've been aware of the existence of chilli thrips for several years, but today, unfortunately, I found evidence of them on several rose bushes in my yard. Chilli thrips are not the same as flower thrips which damage only flowers. These guys damage the foliage and the flowers of not only roses, but scores of other plants. The bad news first:

"Chilli thrips, Scirtothrips dorsalis (Hood), is an important pest of crops in tropical and subtropical regions. An established population of this
pest was first detected in the United States
on landscape roses in Florida in 2005. In
November 2007, chilli thrips were identified
on landscape roses in Houston. Chilli thrips
have also been detected on a number of
ornamental and vegetable plants in retail
stores in Northeast and South Texas.
Host Plants. Chilli thrips have a very broad
host range and may feed on more than 150
plant species in 40 plant families. ..."

The good news is that Chili thrips can't handle freezing weather. So here's hoping for a cold winter!

"It's thought that if you live in a climate where you have 5 or more days per year where the low temp. at night reaches 24.8 degrees Fahrenheit (-4 Celsius) chilli thrips will not be able to permanently establish themselves; otherwise they are on their way."

As you know last winter was very mild giving them a chance to get started after blowing in on the hard winds we've had this summer and last summer.

So what to do? I won't use chemical insecticides. Oils, like Neem oil, are not shown to help, but it is suggested that the damaged foliage be trimmed off, put in a plastic bag, sealed and disposed of. Chilli thrips prefer fresh new growth and I've been soooo good to my roses with organic feeding so they have lots of lush growth and hundred of buds. Rose buds have black streaks, are mishapen and don't open properly. The foliage is wrinkled and crinkly. This is what it looks like. Is anyone else seeing this damage:

Photobucket

Photobucket
I spent the morning trimming off the damaged foliage along with hundreds of damaged buds. Not all the roses are affected. Mostly it's the ones in the center of the yard where the wind would most likely drop them. They may spread to some of the other roses, but for now I'll just concentrate on removing the damaged foliage that I see.

I'll be withdrawing my offer of roses at the plant swap coming up next week.

If the hoped for cold winter doesn't materialize to take care of the chilli thrips I'll start removing the least favorite roses and anything else that might be affected and replacing them with plants that aren't subject to them. That will take some research, but so far I haven't seen ornamental grasses, succulents, bougainvilleas, shrimp plants or phlox on the list.

More information here:

http://www.texasgardener.com/Newsletters/090909/

There are links to photos on this site showing what damage to different plants looks like:

http://www.mrec.ifas.ufl.edu/lso/thripslinks.htm#MANAGEMENT

Stuff happens and we just have to go with the flow and do the best we can.

Here is a link that might be useful: TAMU edu/extension/publication on chilli thrips in Texas ...


Follow-Up Postings:

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RE: Chilli thrips in San Antonio ...

Thanks. I have been wondering what was wrong with most of my roses.


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RE: Chilli thrips in San Antonio ...

Hi Roselee, thank you for this info. I am glad to read this so that I know what to expect in my roses. I went on that TAMU link you posted and had a discussion with my husband. He mentioned if Severn dust or diatomaceous earth would help.

I am so sorry about your roses. My Angel Face is blooming again this week. I hope those pesky thrips would not find my baby and have a party. Do you think it is wise for me not to bring cuttings to the swap event? Let me know and thank you again.


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RE: Chilli thrips in San Antonio ...

Sorry I mean Sevin dust.


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RE: Chilli thrips in San Antonio ...

Me too Kathy. When I saw the flowers were not opening well I thought the flower thrips had come back after having the garden free of them for a few months. There are natural predators that control flower thrips if insecticides are not applied. Unfortunately insect predators only work for chilli thrips in a controlled greenhouse environment.

Mamachile, I think it will be fine to bring rose cuttings to the swap as long as they are not showing symptoms of chilli thrip damage. This is the perfect time of year to propagate roses and maybe we won't have a problem next year if we have enough cold days to knock the chilli thrips back.

Sevin has NOT been shown useful in controlling chilli thrips. I would be very reluctant to use it anyway as it is extremely lethal to bees. It's carried back to the hives on their bodies and it kills the bee larvae and eventually the whole hive. Europe has banned its use. Look up 'Sevin and bees' on the internet to read about it.

If you want to spray an insecticide products containing the active ingredient Spinosad is recommended. It has the lowest toxicity toward beneficial insects and is effective. But there are already reports of chilli thrips becoming resistant to it.

I read one report of a home gardener very carefully applying diatomaceous earth to the tips of the foliage with a brush so as not to kill too many beneficial insects. They felt it had cut down on the damage in their gardens so that might work too although this treatment hasn't been confirmed by research.

It's a mess, but at least it helps to be aware until a sure remedy is found. When there is a problem we just have to garden around it the best we can.

The links in the first message have a lot of information so we know what to watch for.


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RE: Chilli thrips in San Antonio ...

Thank you Roselee, I saw that report about sevin and bees. This is beneficial info.


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RE: Chilli thrips in San Antonio ...

Thank you so much Roselee for the uptodate information about the Chili Thrips. We have it on roses and also on many chili plants. It has also spread to many other plants like Jasmine and Lime seedlings.
Thanks once again.
Chitra


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RE: Chilli thrips in San Antonio ...

Has anyon tried home made insecticide soap?

I also found this:

1 pint spring water
1 teaspoon Tabasco
2 large crushed garlic cloves


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RE: Chilli thrips in San Antonio ...

According to the University of Florida site (below) two brands of insecticidal soaps were not found to be effective. However, it says that products containing spinosad are effective and it has the lowest toxicity of all the insectices listed. So I've been researching spinosad this morning. It's considered 'organic' and approved for use in organic gardens plus being one of the most effective against chilli thrips. It should be sprayed when bees are not active, but does not harm bees after it dries.

These are some brands that contain spinosad:

Borer, Bagworm, Leafminer & Tent
Caterpillar Killer, Ferti-Lome
Bull�s-eye� Bioinsecticide, Gardens Alive

Lawn & Garden Spray Spinosad�
Concentrate, Green Light

There are some other brands offered on Amazon.com. Do a search for 'spinosad' to find them.

I'm going to check and see what Lowes carries.

Here is a link that might be useful: The compounds in bold yellow type have been tested at least once and appear to be effective at significantly reducing the population of this pest.


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RE: Spinosad for Chilli thrips in San Antonio ...

I didn't find anything containing spinosad at Lowes, but a neighborhood independantly owned hardware store had GreenLight Lawn and Garden Spray with Spinosad.

The instructions say: "This product is toxic to bees exposed to treatment for three hours following treatment." Another site confirms it does not harm bees after it dries. I'll spray at dusk.

Also says: "Spinosad does not significantly impact predatory beneficial insects, predatory mites and spiders while controlling target pests." That's good to hear.

The price of the GreenLight product was $16 for 16 ounces. The application rate is four tablespoons per gallon.

Under the 'Home Gardens' section it's recommended to wait 4 to 5 days before reapplication. It also recommends not to use it more than 6 times a season.

So here we go ...


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RE: Chilli thrips in San Antonio ...

I bought spinosad at our local nursery, you are more likely to find it at a nursery with organic products.

Well, I don`t want them! We don`t have enough freezing weather to kill them off. Eeek! It`s always something. We have formosa termites on the island now.

See ya`ll Saturday.
Tally Ho!


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RE: Chilli thrips in San Antonio ...

It may just be me but if I had invested a lot of time andmoney in specialty roses, I would seriously consider digging them up, aggressively trimming them back (both roots and foliage) and put them in the freezer for the required amount of time and then keep them in doors until the weather meet the chill requirements to clear the little buggers. I am not a pesticide person either but I don't give up easy...my turtles are so fat from the spring locusts:)


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RE: Chilli thrips in San Antonio ...

Bumping this up in case anyone hasn't seen it.


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RE: Chilli thrips in San Antonio ...

The people at the Natural Gardener did not seem to be to upset about it. She just said to treat it like thrips. I have not had experience at it so I have not a clue. I do not know what they do...she was distracted away after telling me that they have been in the Austin area for 5 years.


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RE: Chilli thrips in San Antonio ...

Well, I hope the Natural Gardener person is right but I'm not so sure they can be easily 'treated'. I'm surprised she said to 'treat' like ordinary thrips, flower thrips for instance, because that requires an insecticide. The organic gardeners are advised not to spray for flower thrips and a predatory thrips will show up and other beneficial insects which will keep them in check if not thoroughly eliminate them. That has been my experience. Unless she meant by 'treat' to not do anything. From what I read on the internet this doesn't work with chilli thrips as there are not sufficient beneficial insects to control them. Another thought is that Austin gets a little colder most winters than San Antonio so maybe they don't get much of a foothold there.

Yesterday, I saw some damaged leaves on the coral vine such as I've never seen before. They had the brownish streaky patches just like some of the photos on the link below.

I took several sheets of white paper, made a slight funnel with them, held them under a leaf and tapped it. Along with some teeny dust size black dots of what I think was frass I saw one tiny yellow dot moving. It was less than the size of period at the end of this sentence. I focused on it using a 10X jewelers loop and the tiny insect, 1/10 the size of a flower thrips came into view. It was unmistakable a chilli thrips, had the little lines on it and everything. And then it flew away in front my of very eyes (to use an old expression).

I then took the paper to an opened rose that had the brown streaks, tapped it, out dropped two little spiders which quickly ran off the paper. Were they eating the chilli thrips? I don't know. But remaining on the paper were four tiny yellow dots that were moving. Putting the loop on them I could see they were the immature forms of chilli thrips; no wings.

There is also suspicious looking damage to the leaves of the Texas smoke tree. To treat the tree would take a lot of insecticide. To treat the coral vine in the top of the trees would be impossible without using a large amount of a powerful systemic insectacide.

Of course the leaves on both these plants will be dropping in a month or two. Hopefully, a cold winter will cut back on the chilli thrips numbers. Otherwise, we'll just have to learn to live with the damage. Maybe we'll just get used to seeing it.

Here is a link that might be useful: When the page appears scroll up for photos of chilli thrips and the damage they do ....


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RE: Chilli thrips in San Antonio ...

Maybe the natural gardener lady's sense of calm came because she, herself, has not actually had to deal with them yet. On the other hand we have gotten used to many pest that seemed horrendous at the outset (fireants). Don't get me wrong. I am not minimizing your pain or the risk to gardening as we know it. I am praying for a predator to realize these are tasty tidbits and praying for more knowledge and flexibility. I am praying for a cold winter.

I was living in Hawaii when whiteflies first made their appearance. IT was an ugly thing. Their population exploded exponentially. Their were so many whiteflies that our ceilings were coated in them. They were absolutely everywhere. They smothered a lot of leaves in sheltered areas. We had significant ocean breeze. It was disgusting.It took about 6 months and then they had a population implosion and it attained a balance. One never saw them. Bugs and ghechos had learned to eat them. I don't know what happened. I hope something like this happens or they find some natural enemy or some natural enemy them.


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RE: Chilli thrips in San Antonio ...

Mara, I totally agree with what you said. Environmental threats do tend to come into balance, and/or we just learn to live with them. Life goes on; maybe not exactly the same as it was, but it goes on.

Many years ago I read a three volume set of books on the history of the world. At the end the author was interviewed. He was asked what would be his summation of history after all the study he'd done. His answer, "Life goes on."

That's the only thing I remember from reading those three big books. That was the Knowledge I'd gained. The rest was just information. Knowledge is far more important.

Happy gardening!


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RE: Chilli thrips in San Antonio ... ...

More information. Noticed the leaves on Henry Duelberg salvias in the front yard are all looking pale, very similar to spider mite damage, but close inspection with the loop showed no webbing. Of course, I can usually see the webs w/o magnification.

Shook the leaves over the white paper and sure enough the little yellow specks were running around. And I do mean little. Looked with the loop and bingo -- positive ID for chilli thrips. There were also a few even faster moving pale spiders just a little bigger than the chilli thrips. Wonder if they were eating them? Hope so. Guess I'll cut back the salvias level with the ground and spray some spinosad around. Sigh ... not going down without a little fight anyway. Maybe not the big guns, but little organic guns for as long as it works.


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RE: Chilli thrips in San Antonio ...

Bummer. Salvia does not succumb to much. Can you get a picture of the salvia leaves? I would be interested in what they look like.


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RE: Chilli thrips in San Antonio ...

Mara, here's a photo of Henry Duelberg leaves. From a distance they look pale, like spider mite damage, but they had no webs and no spider mites. I haven't had spider mites on any thing since I quit spraying insecticides several years ago.


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RE: Chilli thrips in San Antonio ,,, ...

Here's the chilli thrips damaged leaves of Coral vine:


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RE: Chilli thrips in San Antonio ...

HMMMM.I have a lot of salvias. I will keep my eye out for the. AND I am down wind of san antonio on a nice brisk south wind....Thankyou.


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RE: Chilli thrips in San Antonio ...

I noticed the leaves on my Smoketree (Cotinus) look similar to the coral vine leaves. I thought they were dropping due to the weather, now not so sure.


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RE: Chilli thrips in San Antonio ...

Yikes, I might have some on my salvias.


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RE: Chilli thrips in San Antonio ...

Shirley, as was mentioned before the leaves on my smoke tree look suspicious too. I thought it might be due to drought and heat damaged old leaves, but now I'm not so sure. I haven't done the white paper tap test on those leaves though so still don't know for certain.

Mara, I seem to remember mealy cup sage leaves in years past looking something like the leaves I photographed today. I thought at the time one of it's problems was mildew, but maybe the leaves were damaged by some other small sucking insect and yours may be too.

Incidentally, when I first noticed the brown spots on the coral vine leaves I thought it was due to the vine getting dry because I'd seen them wilting. Then I went and looked at another coral vine by the back fence which wilts more than this one and it's leaves looked fine. That's when I got out the white paper and 10 power loop. You might be able to see chilli thrips with a 5 power magnifying glass, but with 10 power they come in really clear.

Interestingly another plant that is susceptable to hosting chilli thrips is blue plumbago. I have a lot of those and they all look great.

Hoping these cool temps at least will slow the little rascals down. Hey, we got 3 inches of rain today :-)


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RE: Chilli thrips in San Antonio ...

My Lady in Red Salvia has looked just like your Henry Duelburg all summer, I just keep cutting them back. I thought it was spider mites, but saw very few webs. I just shook a salvia plant over white paper and used a magnifying glass. One insect flew before I could see it but the other one looked a lot like Scirtothrips dorsalis. I'm no scientist so can't positively ID it. I'm in Tarrant County.


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RE: Chilli thrips in San Antonio ...

Pam, thanks for the report. Hopefully it isn't chilli thrips or if it is they won't get a foothold since you have colder winters. I have a few more plants I'm going to check.


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RE: Chilli thrips in San Antonio ...

bump. just wondering what you are seeing this year. something is eating my rose buds. not sure which thrip, going to get the spinosad today and talk to my nursery folks. i have SO many ladybugs i don't want to hurt them. and won't!


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RE: Chilli thrips in San Antonio ...

Ilovemyroses, I'm not seeing any damage so far this year. That's probably because chilli thrips are most active in hot weather. They are very tiny, about one 10th of the size of flower thrips so you wouldn't see 'eating' damage to rose buds, but the brown streaks on rose buds (see photo in first post above) are very distinctive.

You can see the very common flower thrips running around in a rose bloom. They cause browning on the edges of the rose petal..

As for the leaves other sucking insects can cause the wrinkling of the leaves with dead spots as well as chilli thrips. The only sure diagnosis would be seeing chilli thrips which requires 10 power magnification. I use a jeweler's loupe to see them.

Chilli thrips are relatively so new to Texas that I doubt many nursery people know much about them.

I hope you don't have them. Although there have been reports of them in the Dallas area there's a very good chance that they are not as wide spread as they are in warm winter climate cities such as San Antonio, where I live.


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RE: Chilli thrips in San Antonio ...

We had a bad case of Chilli Thrips last year also. Not only in my yard, but all over town! I got so used to what it looked like, that I could spot it on roses while driving by in other neighborhoods. I had to cut absolutely everything back and trash the prunings a few times. It went on all summer and into fall, but finally quit. I haven't seen any of that this year so far, but the regular thrips have arrived en masse. We didn't get down into the 20s at all, unfortunately. I think we only got down to freezing in my area once.


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RE: Chilli thrips in San Antonio ...

Brittie,I haven't noticed any damage here either. Maybe it's too early and not hot enough yet or maybe a big infestation like last year isn't going to happen.

The Houston Rose Society is devoting a page to chilli thrips so we might be able to keep up with any developing news about chilli thrips there.

Here is a link that might be useful: Houston Rose Society Chilli Thrips Page...


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RE: Chilli thrips in San Antonio ...

Or maybe we'll have to enjoy our gardens in spring and early summer and cut things back in later summer when it seems the chilli thrips are most active. That would save on water anyway.


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RE: Chilli thrips in San Antonio ...

Ive been fighting thrips on my blueberry bushes for 3 years now in South Houston. They reck shop on new growth late in the fall season and thats the growth that produces your flower buds for spring fruit. Ive been using spinosad for 3 years and try not to spray untill after harvest. They seem to peek in Aug and Sept in my area. Ive done alittle research on them and kaolin clay (surround) is suppost to be pretty effective on thrips plus it helps plants deal with heat which is a bonus in my area. I ordered some surround this spring and will start using it after harvest this year. Hopefully I wont have to spray spinosad anymore. I did notice after spraying spinosad it would knock them back for a couple weeks then seemed like they came back even stronger. It does kill beneficials as well. Dont believe every thing you read on those labels. The lady bugs and lace wings were no where to be found after spraying for months! Dont use it unless you have too. I believe it does more harm than good. A healthy population of lace wings and lady bugs I think can possibably keep there numbers in check but Im afraid they are here to stay. The only plants I dont see alot of damage on here from thrips are rabbiteye blueberries, okra and tomatoes. They do hit the rabbiteyes but not very much at all. Bellpepper, black berry, strawberry, Southern High Bush Blueberry all get attacked in a bad way.


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RE: Chilli thrips in San Antonio ...

Blueboy, it looks and sounds like chilli thrips could be on par with one of the Biblical plagues of Egypt! Even worse than threatening our home gardens is what they can do to the farms that grow our food. Plus more and more insecticides will be used indiscriminately to try to eliminate them which, as you say, will kill off more beneficial insects such as the very insects that might help control the chilli thrips as well as our wild bees and honey bees that pollinate our food crops, not to speak of what harm the chemicals might cause humans. I wonder how they deal with them in Sounthern Asia where they come from? There are probably beneficial insects that keep them in check, but it might take a good while to build up sufficient numbers to control them here and that isn't going to happen if we keep spraying insecticides. Talk about a vicious circle! Hopefully something benign like spraying kaolin clay, sold as "Surround", will prove to be a successful control. Be sure and keep us posted on how it works for you this coming year.


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RE: Chilli thrips in San Antonio ...

I just ran across the excellent article on chilli thrips linked below. However, I can't see how using the insecticides mentioned under the heading of 'Chemical Control' would not harm its natural enemies as well.

Here is a link that might be useful: University of Florida Article on Chilli thrips ....


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