Jump to content

What is this eating my plants?


Batty

Recommended Posts

Got the same damage on my grapes. I got 2 vines. One has no problems while the other was completely finished off by some leaf eating parasite. Found only one small insect with green body and red head. Never more. Sprayed with several (chemical free) sprays (garlic, tabacco, chlli). No woodvinegar though. The sprays didn't help. Curious if someone knowns the culprit. 

 

I never saw any of the damage in progress which might indicate it is done in the dark....

 

Link to comment
Share on other sites

You'll have to use a systemic pesticide I think maybe the one called 'jacket' or similar (Avermectin). Follow the instructions (mask, gloves etc) and you'll be OK. 

If you have a bad conscience about using it don't use anything like a car or a motorbike for a few days, you'll be doing a lot more for the environment. 

Link to comment
Share on other sites

It is most likely a caterpillar (larvae of a moth). Sometimes this type of damage can be caused by a beetle or weevil, adults or larva.  

If you cannot easily spot the responsible critter during the day, go out with a flashlight and look on the underside of the leaves and along the stems in the late night or early morning.  Also, observe if the feeding damage is still under progress or have the caterpillars progressed into pupa stage and are no longer feeding. That's an important issue. Why spray if there is nothing to spray for? Thats the first step in pest management and reducing pesticide use, know the target pest and it's life cycle. 

 

Moths and beetles have complete metamorphosis with four stages, adult, eggs, larva and pupa. The larva stage is the only feeding stage in moths, adult beetles sometimes are the feeders also. Observing which stage and the timing of ocurance is important to know for IPM (integrated pest management).

 

I suspect that the feeding started a few weeks ago and it has probably ceased with the cooler season and stage of development of the insect. Only if the infestation is still under progress should you bother with contact spray or systemic treatment at this time.  If they have stopped feeding, take note of the timing when you first noticed the infestation/damage. Then plan to get ahead of it with a preventive treatment next year, when the same adult moth, beetle or weevil pest may be back to lay eggs which hatch into the larval stage that feed on the plant. 

 

If the infestation is still under progress, you have some choices for treatment, or determining that no treatment is appropriate:

 

1. Do nothing and wait for them to feed out and pupate. It doesn't look like they will devour and kill the entire plant.  The plant will probably re-foliate in February or March as the weather warms up, if irrigated, or when rainy season starts.

2. Mechanical control: if the caterpillars are large and few in number, which is sometimes the case, you can pick them off with your hand, or a gloved hand. Or water spray to knock them off. 

3. Contact spray:  (I advocate for reducing chemical pesticide use, but it's really hard to manage pests without some minimal and responsible use of chemistry. Therefore I'm all for choosing the least toxic control approach, materials and methods of application)

  • Neem products are organic program compatible but are best as a repellant, for early intervention and prevention, not a knock down insecticide for an active infestation. Use this next year when you get ahead of the game. 
  • Pyrethrins (pyrethrum) are natural chrysanthemum flower extract, and potent contact insecticide that biodegrades in 12 - 24 hours. But hard to find in Thailand, and more expensive if you did find it. 
  •  Pyrethroids - (permethrin, cypermethrin, bifenthrin) are synthetic chemistry version of pyrethrum. (Chaindrite products, widely available; Stedfast if you need to tank mix a sprayer, or Crack and Crevice aerosol for a small project ) Relatively low toxicity for mammals but not organic program compatible. Minimal toxicity and environmental contamination if mixed and used responsibly according to instructions.  For a non food plant this is the most practical and economical spray material, and very effective at knock down of an actively feeding pest. And it has some residual effectiveness if you happen to spray during the day and the pest comes out to feed at night; it will ingest the insecticide.
  • Horticultural oil. smothers the pest and affects the respiratory system. Organic program compatible because it biodegrades readily.   
  • Wood vinegar like some have recommended; I just don't use it because I hate the intense smell and acidic chemistry. 

4. Systemic insecticide (like Cooked recommended): applied to the soil for root uptake, and/or sprayed on the foliage for absorption and translocation throughout plant tissues.  Abemectin is not as good as  soil drench, but is whats called a 'translaminar' as a foliar spray; meaning it is absorbed into the leaf and can penetrate through to the other side of the leaf and petiole. It is not fully systemic and mobile in the plant tissues like the neonicotinoids - imidacloprid and dinotefuran. 

 

Maybe more than you wanted to know, but I hope that helps. Don 

 

 

Edited by drtreelove
Link to comment
Share on other sites

22 hours ago, colinneil said:

Please do not use chemicals,organic wood vinegar works.

I boil up a brew of crushed garlic and chopped up chilies ... strain it through a cloth to get out the bits.. get a spray bottle from a 20Bt shop.. spray it on.. usually works for things that like to eat leaves..

Link to comment
Share on other sites

3 hours ago, Laza 45 said:

I boil up a brew of crushed garlic and chopped up chilies ... strain it through a cloth to get out the bits.. get a spray bottle from a 20Bt shop.. spray it on.. usually works for things that like to eat leaves..

Probably works for almost everything that breathes!

Link to comment
Share on other sites

3 hours ago, Laza 45 said:

I boil up a brew of crushed garlic and chopped up chilies ... strain it through a cloth to get out the bits.. get a spray bottle from a 20Bt shop.. spray it on.. usually works for things that like to eat leaves..

For ants, I use cloves but not sure100%  it would work for that, it would be interesting to try, a handful of cloves boiling in half a litre and then spray its terrible for ants so maybe it would worth the trying? I learn that for ants only a few months ago, right now I have no problem like that in the garden otherwise I would have tried. 

Link to comment
Share on other sites

3 hours ago, Laza 45 said:

I boil up a brew of crushed garlic and chopped up chilies ... strain it through a cloth to get out the bits.. get a spray bottle from a 20Bt shop.. spray it on.. usually works for things that like to eat leaves..

This and other home concoctions and commercial products, including clove oil, rosemary oil, etc could be a good repellent if you get the timing right for stage of life cycle for the pest. It will only have a residual effectiveness for about a week or two, so repeated spaying is needed.  And of course the spray bottle applicator is only good for very small plant or plants, not a tree or crop. 

 

When using this or especially wood vinegar, protect your eyes. The harsh concentrated substances may be hazardous for the applicator if not so much for the environment. 

Edited by drtreelove
Link to comment
Share on other sites

14 minutes ago, Tchooptip said:

For ants, I use cloves but not sure100%  it would work for that, it would be interesting to try, a handful of cloves boiling in half a litre and then spray its terrible for ants so maybe it would worth the trying? I learn that for ants only a few months ago, right now I have no problem like that in the garden otherwise I would have tried. 

Can you be a bit more specific?

I have ants trying to colonize my coffee trees.

How should I proceed exactly with cloves? 

Dry cloves? What quantity? Mix with boiled water or boil them together? Spray where and when, I mean spray all over the trees or specifically at the ants, and at anytime or better in the evening?

Anything useful is much appreciated...

 

Link to comment
Share on other sites

38 minutes ago, Brunolem said:

Can you be a bit more specific?

I have ants trying to colonize my coffee trees.

How should I proceed exactly with cloves? 

Dry cloves? What quantity? Mix with boiled water or boil them together? Spray where and when, I mean spray all over the trees or specifically at the ants, and at anytime or better in the evening?

Anything useful is much appreciated...

 

I do not remember how did I find it ...but I had many cloves I bought at Macro, I boiled let's say half a cup of cloves  in half a litre at least ten minutes in slowest bowling possible, then sprayed the liquid with a little spray bottle I had already, (after it was cold of course LOL)  incredible, at the same second every ants died, so much so I could hardly believe it,  now I have always a spay ready, by the way  very very few is needed, the only drawback if I dare say, it is logically a brown liquid so cannot use it everywhere inside house, but efficacity guarantee 100% :thumbsup: 

Let me know of the results if you'll have a try at it.

Link to comment
Share on other sites

3 minutes ago, Tchooptip said:

I do not remember how did I find it ...but I had many cloves I bought at Macro, I boiled let's say half a cup of cloves  in half a litre at least ten minutes in slowest bowling possible, then sprayed the liquid with a little spray bottle I had already, (after it was cold of course LOL)  incredible, at the same second every ants died, so much so I could hardly believe it,  now I have always a spay ready, by the way  very very few is needed, the only drawback if I dare say, it is logically a brown liquid so cannot use it everywhere inside house, but efficacity guarantee 100% :thumbsup: 

Let me know of the results if you'll have a try at it.

It would be only for external use.

I will try to find the cloves first...

Thanks for the tip...

 

Link to comment
Share on other sites

1 hour ago, drtreelove said:

This and other home concoctions and commercial products, including clove oil, rosemary oil, etc could be a good repellent if you get the timing right for stage of life cycle for the pest. It will only have a residual effectiveness for about a week or two, so repeated spaying is needed.  And of course the spray bottle applicator is only good for very small plant or plants, not a tree or crop. 

 

When using this or especially wood vinegar, protect your eyes. The harsh concentrated substances may be hazardous for the applicator if not so much for the environment. 

I haven't heard of wood vinegar before... what is it ans where do you get it? Thanks...

Link to comment
Share on other sites

18 hours ago, drtreelove said:

Maybe more than you wanted to know, but I hope that helps.

Don, off topic but you appear to be a chemicals man. I need the name of a pre-emergent herbicide before planting rice and corn. Am I right in assuming a pre-emergent is the same as a systemic herbicide as I need one to control grasses.

Link to comment
Share on other sites

4 hours ago, GreasyFingers said:

Don, off topic but you appear to be a chemicals man. I need the name of a pre-emergent herbicide before planting rice and corn. Am I right in assuming a pre-emergent is the same as a systemic herbicide as I need one to control grasses.

Pre-emergent and systemic herbicide is not the same.  A pre-emergent herbicide is spread/sprayed on bare ground and prevents broadleaf weed and grass seeds from sprouting, a post-emergent is contact or systemic that is sprayed on green foliage to kill weeds that are already in a green growth phase.

 

A pre-emergent would prevent seeds of any kind from sprouting, including your crop. But may be appropriate for preventive weed control in a field where the crop was already in vegetative stage. But I don't know what pre-emergents are available here, and what would be appropriate for use without harm for the field crop. 

 

I recommend that you post this question, or that a moderator move this to the Farming in Thailand Forum, (not organic subforum). And we can continue the discussion there with benefit of actual rice and corn grower input; which I am not. 

Link to comment
Share on other sites

Boil tobacco,garlic and pepper -strain and use as required

Add neem oil if especially bad

For ants mix diatomaceous earth ( available at most swimming pool dealers  ) with sugar and water and leave in container where the ants have easy access. They take it back to the nest and kill the colony

Link to comment
Share on other sites

Caterpillars usually start at the edge of a leaf and work their way in, Roundish holes more usually small beetles or weevils, but could be snails. You need to search carefully for potential culprits. If their is any new growth which is undamaged, check it every day, and if damaged, start hunting. As also said, see if it only happens at night.

Link to comment
Share on other sites

29 minutes ago, rickudon said:

Caterpillars usually start at the edge of a leaf and work their way in, 

some do some don't. that's why you have to identify the pest in order to take appropriate action, or not. 

 

https://www.google.co.th/search?q=caterpillar+plant+damage&dcr=0&tbm=isch&source=iu&ictx=1&fir=I20um_4vnits8M%3A%2CmL7Mo9j2rPshEM%2C_&usg=__oHG2GUVRIldtTUBTByF7cSpDCx4%3D&sa=X&ved=0ahUKEwiirsCqkN_YAhXMy7wKHSvMA6EQ9QEILDAA#imgrc=I20um_4vnits8M:

Link to comment
Share on other sites

If determined to be caterpillars actively feeding, then there is another excellent non-chemical control option:  biological control with Bt (Bacillus thuringiensis). But the caterpillars have to injest it. and they have to be in the early instars (stage of development) to be effective. Timing is everything. 

Link to comment
Share on other sites

On 1/16/2018 at 1:26 PM, Brunolem said:

Can you be a bit more specific?

I have ants trying to colonize my coffee trees.

How should I proceed exactly with cloves? 

Dry cloves? What quantity? Mix with boiled water or boil them together? Spray where and when, I mean spray all over the trees or specifically at the ants, and at anytime or better in the evening?

Anything useful is much appreciated...

 

If you have ants in your coffee trees, then they are most likely there to farm a sucking insect that produces sweet honeydew. Target control for the sucking insect, then the ants will come under control. Or control the ants and the sucking insect will be more readily attacked by their natural enemies if the ants aren't there to defend their "cows". 

 

Identify the insect pest and the type of ant activity.  When you say colonize, do  you mean they are nesting in the coffee plants, or do you see a trail of ants up and down the stem?  Or are they large red weaver ants forming nests. If so, they are a nuisance and bite like hell, but they are important pest predators. 

 

For IPM, and reducing the use of pesticides, chemical or botanicals both which can disrupt the ecosystem, it's always very important to know exactly what pest you are dealing with, it's feeding habits and its life cycle. 

Link to comment
Share on other sites

13 hours ago, drtreelove said:

If you have ants in your coffee trees, then they are most likely there to farm a sucking insect that produces sweet honeydew. Target control for the sucking insect, then the ants will come under control. Or control the ants and the sucking insect will be more readily attacked by their natural enemies if the ants aren't there to defend their "cows". 

 

Identify the insect pest and the type of ant activity.  When you say colonize, do  you mean they are nesting in the coffee plants, or do you see a trail of ants up and down the stem?  Or are they large red weaver ants forming nests. If so, they are a nuisance and bite like hell, but they are important pest predators. 

 

 

Yes, the ants are farming!

I don't know what exactly, but it forms a sort a white sticky "cocoon", generally at the intersection between a leaf and its branch.

If I let it develop, then the whole area turns black, as the pests feed on the coffee cherries.

 

I follow that closely now and remove all the white "cocoons" simply by spraying water directly at them.

 

It works, but the ants keep on trying again...

 

Link to comment
Share on other sites

On 1/18/2018 at 10:28 AM, Brunolem said:

Yes, the ants are farming!

I don't know what exactly, but it forms a sort a white sticky "cocoon", generally at the intersection between a leaf and its branch.

If I let it develop, then the whole area turns black, as the pests feed on the coffee cherries.

 

I follow that closely now and remove all the white "cocoons" simply by spraying water directly at them.

 

It works, but the ants keep on trying again...

 

Good on you friend, you have diagnosed the issue and found the appropriate control.

 

The white masses are almost certainly "mealy bugs", a sucking insect related to 'scale; insect pests, common on coffee plants. You have found a good, IPM/organic program friendly method of mechanical control, to wash off the mealy bug masses and the "sooty mold" that grows on their 'honeydew' excretions.  Contact sprays are ineffective because this pest protects itself with the white waxy coating. Systemic insecticides are not appropriate because it is a food product plant. 

BTW, The sooty mold is not pathogenic, but when heavy on the leaf surfaces it can block sunlight and therefore suppress photosynthesis. 

The ants will continue to trail up and harvest any remaining honeydew deposits, even when the mealy bugs are gone. The ants are not harmful to the plants, except only when they protect the pests from natural predators. Be patient and concentrate on the mealy bug control and eventually the ant trails will cease.

 

But if you choose to control the ants, another mechanical control would be to paint the base of the woody stems with a 'tanglefoot'' commercial product, or make your own if you can find a recipe. Chemical control would stop the ants same day; spraying the stems with a pyrethroid  is cheap and easy and relatively low toxicity and minimal environmental exposure.  Avoid soil drenching and foliar canopy spraying, therefore the chemistry is limited to maybe six vertical inches of the woody stem on the bark surface. A pyrethroid will not penetrate and go systemic and translocate into the coffee beans.  For a small number of plants, Chaindrite Crack and Crevice Spray (under 100 baht, available almost everywhere, I just bought some at my tiny mooban mini shop) has a.i.'s (active ingredients) of alphacypermethrin and bifenthrin, which will give you about a month of residual activity, more than enough to get control with one application. 

 

My advise is to walk  your coffee plants and any other plantings at least weekly if not daily, and inspect for early onset of pest activity. If you get ahead of an infestation you will limit damage and be able to use least toxic methods and materials for control.

When we had a 10 rai farm/orchards in Mae Jo, Chiang Mai, I made it a daily ritual for a morning IPM inspection walk through, coffee cup in hand, with dog and cat following for fence breach inspections, poacher and rodent control.

 

And you can even go further and learn what pest and disease issues are common on the plants you grow in your locale. If you can anticipate potential infestations and infections and employ preventive measures, you will limit plant damage and loss, and you will be able to minimize or even eliminate the use of harsh chemistry.  

Link to comment
Share on other sites

2 hours ago, drtreelove said:

Good on you friend, you have diagnosed the issue and found the appropriate control.

 

The white masses are almost certainly "mealy bugs", a sucking insect related to 'scale; insect pests, common on coffee plants. You have found a good, IPM/organic program friendly method of mechanical control, to wash off the mealy bug masses and the "sooty mold" that grows on their 'honeydew' excretions.  Contact sprays are ineffective because this pest protects itself with the white waxy coating. Systemic insecticides are not appropriate because it is a food product plant. 

BTW, The sooty mold is not pathogenic, but when heavy on the leaf surfaces it can block sunlight and therefore suppress photosynthesis. 

The ants will continue to trail up and harvest any remaining honeydew deposits, even when the mealy bugs are gone. The ants are not harmful to the plants, except only when they protect the pests from natural predators. Be patient and concentrate on the mealy bug control and eventually the ant trails will cease.

 

But if you choose to control the ants, another mechanical control would be to paint the base of the woody stems with a 'tanglefoot'' commercial product, or make your own if you can find a recipe. Chemical control would stop the ants same day; spraying the stems with a pyrethroid  is cheap and easy and relatively low toxicity and minimal environmental exposure.  Avoid soil drenching and foliar canopy spraying, therefore the chemistry is limited to maybe six vertical inches of the woody stem on the bark surface. A pyrethroid will not penetrate and go systemic and translocate into the coffee beans.  For a small number of plants, Chaindrite Crack and Crevice Spray (under 100 baht, available almost everywhere, I just bought some at my tiny mooban mini shop) has a.i.'s (active ingredients) of alphacypermethrin and bifenthrin, which will give you about a month of residual activity, more than enough to get control with one application. 

 

My advise is to walk  your coffee plants and any other plantings at least weekly if not daily, and inspect for early onset of pest activity. If you get ahead of an infestation you will limit damage and be able to use least toxic methods and materials for control.

When we had a 10 rai farm/orchards in Mae Jo, Chiang Mai, I made it a daily ritual for a morning IPM inspection walk through, coffee cup in hand, with dog and cat following for fence breach inspections, poacher and rodent control.

 

And you can even go further and learn what pest and disease issues are common on the plants you grow in your locale. If you can anticipate potential infestations and infections and employ preventive measures, you will limit plant damage and loss, and you will be able to minimize or even eliminate the use of harsh chemistry.  

Well, thank you very much for all this information.

 

The ants...I know all too well...they are everywhere, all kinds of them, the worst in term of pain inflicted being the smallest one...big red ants are a joke compared to them.

 

My coffee trees are shaded by mango trees, which the red ants love so much for nesting, and in other parts protected from the sun by a net.

 

Ants always find a way to go around obstacles...one of their favorite stunts is to let themselves fall from the mango trees down to the coffee trees or to the net, or to me when I go on the offensive.

 

As you explain, I go for a close inspection of each coffee tree at least once a week, so ants don't really have time to do much damage.

 

I don't use any chemicals on anything I grow, the world and notably Isaan being poisoned enough like that.

 

I am also in the process of growing bananas, the good little ones which are hard to find around here and pretty expensive...so far no major pest attacks on these trees, which are not really trees...

Edited by Brunolem
Link to comment
Share on other sites

On 1/20/2018 at 12:49 PM, Brunolem said:

Well, thank you very much for all this information.

 

The ants...I know all too well...they are everywhere, all kinds of them, the worst in term of pain inflicted being the smallest one...big red ants are a joke compared to them.

 

My coffee trees are shaded by mango trees, which the red ants love so much for nesting, and in other parts protected from the sun by a net.

 

Ants always find a way to go around obstacles...one of their favorite stunts is to let themselves fall from the mango trees down to the coffee trees or to the net, or to me when I go on the offensive.

 

As you explain, I go for a close inspection of each coffee tree at least once a week, so ants don't really have time to do much damage.

 

I don't use any chemicals on anything I grow, the world and notably Isaan being poisoned enough like that.

 

I am also in the process of growing bananas, the good little ones which are hard to find around here and pretty expensive...so far no major pest attacks on these trees, which are not really trees...

I had my feet swarmed by the little red ankle biters the other day, so I can relate to what you say.  It's been awhile since I had any of the kamikaze dive bombers from the mango trees on me, thank God. Most ants are not directly harmful to plants, just a nuisance; and they have their place in the ecosystem. 

 

BTW, everything in our physical universe has a chemical basis, even air and water. It is my pet peeve when people make blanket statements condemning  chemicals or pesticides, without even considering which chemicals they are talking about.  That's why I have made an effort to learn the difference in harsh chemistry that is environmentally contaminating,  and useful natural, biological substances that are less toxic and disruptive.  Biopesticides are the new frontier.  And to employ practices like  IPM that start with monitoring and knowing exactly what you are dealing with before you decide to implement controls. 

 

We can take it a step further and learn as much as possible about the plants under our care and their requirement for management. We can also build the soil fertility and manage water, which are the first lines of plant health care and preventive treatment. This is the way to minimize need for chemical or botanical substances in pest and disease management. "High Nutrient Density" soil minerals and biological activity building and balancing is the state of the art.  

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.







×
×
  • Create New...