Stem Borers/Cats - Total War

mattypacks

Well-Known Member
Eastern MA backyard grower. Recently during a tie down session on my OG#18, I noticed one of the branches was pretty soft at one spot. Took a closer look and noticed a tiny hole 3/4 of the way up on one of the main branches. Fuck. Immediately I slit an inch in each direction from the hole, couldn't find the borer inside. Poked holes up and down that branch at intervals with a needle then patched the wound up with grafting tape.
722 OG18.jpgborer1.jpg

Looked up and down the main stalk and noticed 3-4 more holes either just below or on top where the branches intersect to the stalk. Also found a hole right in between the two mains where I topped. Fuck. Needle aint gonna help me with these ones.
borer2.jpgborer6.jpgborer7.jpgborer4.jpg

I was noticing cats hanging out in webs between the leaves of various new tops across most of the plants, so I decided to spray BT earlier this season. I know budworms are an issue for me, so not a problem, was gonna start the sprays early this year anyways. The holes were identified about 4 days after my first application of BT, and appeared to be somewhere between 24-72 hours old. About 50-75% of the holes appeared to be "active" with new frass appearing daily. I doubt the BT had much effect since this is the case.
I had probed all the holes I could with thick fishing line and the tunnels run deep. More than likely from the base of the plant all the way up to the top of the main branches. I would assume with all the info I have, that 3-5 stem borers are active inside.
Only two holes appeared in the top 33% of the plant, which could be exit holes. From the research ive done, the first generation will eat up and down, then either pupate inside or exit and drop down to pupate, hatch and breed and do it all over again.
It makes it all the more difficult that I cant identify which type of borer im dealing with. European corn borer, Eurasian hemp borer, or any of the beetle borers are the suspects. I've had a passion for insects my whole life and have a keen eye for them. Theres no shortage of insects here (I live across the street from 250 acres of woods), but moths stand out in particular since budworms plague my outdoor garden every year, so those are the main guys ill be scouting for.

Not identified as any sort of borer, still dont want any type of moth anywhere near my plants. Last night during a checkup I noticed what appeared to be a click beetle hanging out on top of the hole between the two main branches. I brushed it away not even thinking to capture it to get a second look due to having my mindset totally on moths. Click beetles are everywhere around here, I found another one on my shed after going back to look at the plant a few more times throughout the night that was almost identical to the one I saw on the plant. Unless it was some sort of flathead borer, click beetles cant be the suspect.
borer9.jpg

With moths being in mind (hemp borer + corn borer) I went ahead and ordered yellow sticky traps, wing traps, and pheramone lures for the NY strain of European corn borer. I will be calling one of MA's departments of agriculture tomorrow to see if they have info on the specific types of borers identified in the area which I should have done in advance but I was in a panic trying to stop the hemorrhaging. BT sprays every 3 days. Got parasitic wasp eggs coming in early next week. Diatomaceous earth came in and Ill be applying it to the stalks every night. I also ordered a 1/2 acre dynatrap for general assistance.

Every single day, morning to night, Im out there checking all the plants. So far just the OG is affected and im trying to keep it that way. Culling the plant is NOT an option for me, ill fight this until the end the best I can. Other than the obvious physical and structural damage thats been caused (cankers and splitting of the stalk), there is no wilting, no rot of any kind, and the plant seems generally healthy (so far...). Ill give a good squeeze and bend at damaged points and it still seems solid. I am expecting significantly lower yeilds if she can make it to harvest.
borer10.jpgborer5.jpg

Dealing with the devil here. If anyone has any experience with these guys or have been able to manage them please share your thoughts/knowledge. The damage is already done, and I need to do the best I can to keep it from getting worse.
 

waterproof808

Well-Known Member
Your plant still looks healthy so nothing more you can really do than stick with you plan and hope your plant survives. I've heard from someone else on this site about injecting the bore holes with neem oil and saving the plant. I'd probably try something else besides neem oil, maybe Dipel (BT).
 

See green

Well-Known Member
Good luck man. Im also in the norheast south of you. I too had an attack of stem borer this year. It was a first for me. Not fun at all, they only attacked 2 of my plants but both were the same strain. I discovered it early so I was able to cut the stems and get the worms out. They were about a quarter inch long, whitish body with black heads. This was about 3 weeks ago. I haven't seen anymore new holes or frass. I am hopeful that was it for this season. This is supposed to be the easy part of the grow for us lol..Im just gonna blame it on 2020 ..man what a shitty year!!
 

mattypacks

Well-Known Member
Your plant still looks healthy so nothing more you can really do than stick with you plan and hope your plant survives. I've heard from someone else on this site about injecting the bore holes with neem oil and saving the plant. I'd probably try something else besides neem oil, maybe Dipel (BT).
I was definitely considering filling a dropper with BT, inserting and injecting directly into the holes. Since they already made their way all the way up and down I figure it might be tricky to get it to be as effective as if I did it when they first got in. Missed that window :wall:. It seems like the holes are becoming less active, so maybe this generation is getting close to being done.. Either way, my thought process is if their gonna be chewing out of the plant and the stalks are treated with BT it should still have an effect? I know there is a delay between ingestion and mortality, im just not sure how it would go if they eat the BT on their way out, cease feeding, and then pupate. Maybe the adult moth will die off?

Good luck man. Im also in the norheast south of you. I too had an attack of stem borer this year. It was a first for me. Not fun at all, they only attacked 2 of my plants but both were the same strain. I discovered it early so I was able to cut the stems and get the worms out. They were about a quarter inch long, whitish body with black heads. This was about 3 weeks ago. I haven't seen anymore new holes or frass. I am hopeful that was it for this season. This is supposed to be the easy part of the grow for us lol..Im just gonna blame it on 2020 ..man what a shitty year!!
Yeah man, this is some freak-show shit. It was like hell having to consider chopping branches even just to identify the species. Only the main stalk, and 2 main top branches have active holes, and if I were to cut just one that would be a third of the plant gone right there. Shes a big girl. I weighed in what I may lose towards to end of the season to chopping branches and concluded that ill just wait to see what happens since I eat shit with either option regardless.
Man I wish I could blame 2020, but last year I had one shitty plant that ended up getting hit by borers. It was wayyy later in the season though, like September all the way till chop. I only noticed one maybe two branches that ended up finishing fine but had rotted knuckles where it met the stalk. I was able to kill one of them when harvested. The stuff ive read says both that they'll stop late July to pupate overwinter, and that more generations will show up throughout the season making it harder for me to figure it all out. That might be the source of what im dealing with now though as that soil was composted near by (stalks and stems bagged up and thrown out). But then again, I had no problems prior to last year to begin with, only one plant is affected which was in the middle of a row of 3, and they showed up so much later in the season.
 

thumper60

Well-Known Member
Eastern MA backyard grower. Recently during a tie down session on my OG#18, I noticed one of the branches was pretty soft at one spot. Took a closer look and noticed a tiny hole 3/4 of the way up on one of the main branches. Fuck. Immediately I slit an inch in each direction from the hole, couldn't find the borer inside. Poked holes up and down that branch at intervals with a needle then patched the wound up with grafting tape.
View attachment 4635589View attachment 4635576

Looked up and down the main stalk and noticed 3-4 more holes either just below or on top where the branches intersect to the stalk. Also found a hole right in between the two mains where I topped. Fuck. Needle aint gonna help me with these ones.
View attachment 4635577View attachment 4635582View attachment 4635583View attachment 4635580

I was noticing cats hanging out in webs between the leaves of various new tops across most of the plants, so I decided to spray BT earlier this season. I know budworms are an issue for me, so not a problem, was gonna start the sprays early this year anyways. The holes were identified about 4 days after my first application of BT, and appeared to be somewhere between 24-72 hours old. About 50-75% of the holes appeared to be "active" with new frass appearing daily. I doubt the BT had much effect since this is the case.
I had probed all the holes I could with thick fishing line and the tunnels run deep. More than likely from the base of the plant all the way up to the top of the main branches. I would assume with all the info I have, that 3-5 stem borers are active inside.
Only two holes appeared in the top 33% of the plant, which could be exit holes. From the research ive done, the first generation will eat up and down, then either pupate inside or exit and drop down to pupate, hatch and breed and do it all over again.
It makes it all the more difficult that I cant identify which type of borer im dealing with. European corn borer, Eurasian hemp borer, or any of the beetle borers are the suspects. I've had a passion for insects my whole life and have a keen eye for them. Theres no shortage of insects here (I live across the street from 250 acres of woods), but moths stand out in particular since budworms plague my outdoor garden every year, so those are the main guys ill be scouting for.

Not identified as any sort of borer, still dont want any type of moth anywhere near my plants. Last night during a checkup I noticed what appeared to be a click beetle hanging out on top of the hole between the two main branches. I brushed it away not even thinking to capture it to get a second look due to having my mindset totally on moths. Click beetles are everywhere around here, I found another one on my shed after going back to look at the plant a few more times throughout the night that was almost identical to the one I saw on the plant. Unless it was some sort of flathead borer, click beetles cant be the suspect.
View attachment 4635585

With moths being in mind (hemp borer + corn borer) I went ahead and ordered yellow sticky traps, wing traps, and pheramone lures for the NY strain of European corn borer. I will be calling one of MA's departments of agriculture tomorrow to see if they have info on the specific types of borers identified in the area which I should have done in advance but I was in a panic trying to stop the hemorrhaging. BT sprays every 3 days. Got parasitic wasp eggs coming in early next week. Diatomaceous earth came in and Ill be applying it to the stalks every night. I also ordered a 1/2 acre dynatrap for general assistance.

Every single day, morning to night, Im out there checking all the plants. So far just the OG is affected and im trying to keep it that way. Culling the plant is NOT an option for me, ill fight this until the end the best I can. Other than the obvious physical and structural damage thats been caused (cankers and splitting of the stalk), there is no wilting, no rot of any kind, and the plant seems generally healthy (so far...). Ill give a good squeeze and bend at damaged points and it still seems solid. I am expecting significantly lower yeilds if she can make it to harvest.
View attachment 4635586View attachment 4635581

Dealing with the devil here. If anyone has any experience with these guys or have been able to manage them please share your thoughts/knowledge. The damage is already done, and I need to do the best I can to keep it from getting worse.
Take this as a learning time. If it was one i would say cut the stem 1 inch below the hole,See as you got plenty i would slice the stem with a razer starting at the hole they always go up. try to find the worm if you cant find the worm cut the stem off to save the plant dont wait it will not get better been there done it!
 

potroastV2

Well-Known Member
I am battling cutworms this year too, and they are wiping out my plants. I've never had this problem in San Diego before, and it is really distressing.

I've increased my BT spraying to every 3-4 days, and spread DE on the surface of the medium, yet the problems continue. It sucks.



:mrgreen:
 

mattypacks

Well-Known Member
Take this as a learning time. If it was one i would say cut the stem 1 inch below the hole,See as you got plenty i would slice the stem with a razer starting at the hole they always go up. try to find the worm if you cant find the worm cut the stem off to save the plant dont wait it will not get better been there done it!
Just went and cut in two spots on one of the branches. I fed the fishing line up and down the hole to see how far it went so I knew where to cut. I made a two inch incision about 5-6 inches above and below the hole. No worm, and it really didnt look like much in terms of damage on the inside, especially the top cut, which appeared to look how its supposed to. Ill continue to try this on branches with holes that have more frass coming out as time goes on. I want to save chopping entire branches for a last resort. I also hear that frass sends a signal to other borers that "this is my spot!", and might try to harvest and spread around to other plants. But im seeing such a tiny amount of it that it might not be enough to even work.

I am battling cutworms this year too, and they are wiping out my plants. I've never had this problem in San Diego before, and it is really distressing.

I've increased my BT spraying to every 3-4 days, and spread DE on the surface of the medium, yet the problems continue. It sucks.



:mrgreen:
Sorry to hear that dude. Mother nature is vicious and favors no man. We do our best with what we have and thats all that matters I suppose. Its likely that anything we could use to eradicate any of these guys effectively would hand in hand wipe out the plants too. I guess looking to the future, figuring out the pests habits and life cycle could be valuable information. If they're overwintering in the soil (like many others I love no-till and renewable gardening practices), I certainly dont want this to become an annual thing. I will be doing the same thing with the frequent BT spraying and DE applications, If you end up getting a leg up on your situation id love to hear what helped. I know manual hunting and removal is one of the best ways to deal with cats/worms, but when they're invisible (kinda) that goes out the window..
 

Corso312

Well-Known Member
Eastern MA backyard grower. Recently during a tie down session on my OG#18, I noticed one of the branches was pretty soft at one spot. Took a closer look and noticed a tiny hole 3/4 of the way up on one of the main branches. Fuck. Immediately I slit an inch in each direction from the hole, couldn't find the borer inside. Poked holes up and down that branch at intervals with a needle then patched the wound up with grafting tape.
View attachment 4635589View attachment 4635576

Looked up and down the main stalk and noticed 3-4 more holes either just below or on top where the branches intersect to the stalk. Also found a hole right in between the two mains where I topped. Fuck. Needle aint gonna help me with these ones.
View attachment 4635577View attachment 4635582View attachment 4635583View attachment 4635580

I was noticing cats hanging out in webs between the leaves of various new tops across most of the plants, so I decided to spray BT earlier this season. I know budworms are an issue for me, so not a problem, was gonna start the sprays early this year anyways. The holes were identified about 4 days after my first application of BT, and appeared to be somewhere between 24-72 hours old. About 50-75% of the holes appeared to be "active" with new frass appearing daily. I doubt the BT had much effect since this is the case.
I had probed all the holes I could with thick fishing line and the tunnels run deep. More than likely from the base of the plant all the way up to the top of the main branches. I would assume with all the info I have, that 3-5 stem borers are active inside.
Only two holes appeared in the top 33% of the plant, which could be exit holes. From the research ive done, the first generation will eat up and down, then either pupate inside or exit and drop down to pupate, hatch and breed and do it all over again.
It makes it all the more difficult that I cant identify which type of borer im dealing with. European corn borer, Eurasian hemp borer, or any of the beetle borers are the suspects. I've had a passion for insects my whole life and have a keen eye for them. Theres no shortage of insects here (I live across the street from 250 acres of woods), but moths stand out in particular since budworms plague my outdoor garden every year, so those are the main guys ill be scouting for.

Not identified as any sort of borer, still dont want any type of moth anywhere near my plants. Last night during a checkup I noticed what appeared to be a click beetle hanging out on top of the hole between the two main branches. I brushed it away not even thinking to capture it to get a second look due to having my mindset totally on moths. Click beetles are everywhere around here, I found another one on my shed after going back to look at the plant a few more times throughout the night that was almost identical to the one I saw on the plant. Unless it was some sort of flathead borer, click beetles cant be the suspect.
View attachment 4635585

With moths being in mind (hemp borer + corn borer) I went ahead and ordered yellow sticky traps, wing traps, and pheramone lures for the NY strain of European corn borer. I will be calling one of MA's departments of agriculture tomorrow to see if they have info on the specific types of borers identified in the area which I should have done in advance but I was in a panic trying to stop the hemorrhaging. BT sprays every 3 days. Got parasitic wasp eggs coming in early next week. Diatomaceous earth came in and Ill be applying it to the stalks every night. I also ordered a 1/2 acre dynatrap for general assistance.

Every single day, morning to night, Im out there checking all the plants. So far just the OG is affected and im trying to keep it that way. Culling the plant is NOT an option for me, ill fight this until the end the best I can. Other than the obvious physical and structural damage thats been caused (cankers and splitting of the stalk), there is no wilting, no rot of any kind, and the plant seems generally healthy (so far...). Ill give a good squeeze and bend at damaged points and it still seems solid. I am expecting significantly lower yeilds if she can make it to harvest.
View attachment 4635586View attachment 4635581

Dealing with the devil here. If anyone has any experience with these guys or have been able to manage them please share your thoughts/knowledge. The damage is already done, and I need to do the best I can to keep it from getting worse.

I've been dealing with them for years.. I've always called them corn borers. If I catch em quick I rip the branch off before they get to the main stem. To be honest I've never had any luck slowing them down or stopping em. I just grow more plants outdoors and anticipate losing a few of them to borers. I've tried planting late and that didn't work. Good luck.. It's a real kick in the nuts when mid flower. Beautiful plants start drooping overnight and die off a few days later.
 

codster25

Well-Known Member
This is a first for me too, haven’t seen actual holes before. Has anyone had experience with this that resolved itself? I sprayed some doctor doom spray.
image.jpg
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mattypacks

Well-Known Member
I've been dealing with them for years.. I've always called them corn borers. If I catch em quick I rip the branch off before they get to the main stem. To be honest I've never had any luck slowing them down or stopping em. I just grow more plants outdoors and anticipate losing a few of them to borers. I've tried planting late and that didn't work. Good luck.. It's a real kick in the nuts when mid flower. Beautiful plants start drooping overnight and die off a few days later.
In my case, I think they started at the base and went up up up. I would totally pull a branch if it was isolated. Ill keep my eye out for isolated attacks on the other plants. I always like to factor in losses based off of past seasons, pretty much all of it comes from some sort of caterpillar. Im really interested in seeing the impact of the parasitic wasps I introduce and hope they not only stop the borers from increasing but also help with the budworms in flower.

You're right, kick in the nuts is an understatement, one of the worst feelings ever knowing although they look healthy now that one day soon that wont be the case.. Ill do my best to support the main branches and treat at the first sign of fungal infection, man if she makes it to September itll be a shit show. I might experiment with grafting and amputations if it comes down to it cuz why not! Thats the fun in it (even though this is not a fun situation whatsoever lol), not just succeeding but failing, trying new things, learning from your mistakes etc
 

mattypacks

Well-Known Member
This is a first for me too, haven’t seen actual holes before. Do you think this will decimate the crop?
View attachment 4635929
View attachment 4635930
Hard to say man, especially if holes arent present. Those canker looking areas do look very similar to what im seeing, but theres a wide range of blemishes that can appear on cannabis or any plant for that matter, with a wider range of reasons why they show up. Keep an eye out for holes, black spots on stems/stalks, wilting or dying off, splitting, and try to think ahead if the cankering gets worse. The major sign in my case wasnt just the holes but the presence of "frass", itll look like a mini pile of sawdust, most of the time thats how you know where the holes are. I dont think it would be impossible for them to enter from the soil and leave no obvious signs from the outside.
 

mattypacks

Well-Known Member

These are two nice articles with a lot of info about the European Corn Borer specifically.
A specific point of interest is where the use of Beauveria Bassiana is mentioned.
"Beauveria bassiana is an entomopathogenic fungi that causes white muscadine disease in a range of insects including whiteflies, aphids, thrips, grasshoppers and certain types of beetles. It differs from Nosema locustae in that it does not need to be ingested by the host; B. bassiana spores simply need to come in contact with a host. Once the host insect is infected, the fungus rapidly grows inside of the insect, feeding on the nutrients present in the host's body and producing toxins in the process. When the host dies, the B. bassiana covers the carcass in a layer of white mold that produces more infective spores. "

I wonder if injecting this into borer holes would work without causing further issues. Ive never even heard of this stuff. Its pretty expensive (https://www.arbico-organics.com/product/5119/caterpillar-control-deciduous-fruit-trees). I may consider giving it a try if things dont calm down in the near future.
 
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codster25

Well-Known Member

These are two nice articles with a lot of info about the European Corn Borer specifically.
A specific point of interest is where the use of Beauveria Bassiana is mentioned.
"Beauveria bassiana is an entomopathogenic fungi that causes white muscadine disease in a range of insects including whiteflies, aphids, thrips, grasshoppers and certain types of beetles. It differs from Nosema locustae in that it does not need to be ingested by the host; B. bassiana spores simply need to come in contact with a host. Once the host insect is infected, the fungus rapidly grows inside of the insect, feeding on the nutrients present in the host's body and producing toxins in the process. When the host dies, the B. bassiana covers the carcass in a layer of white mold that produces more infective spores. "

I wonder if injecting this into borer holes would work without causing further issues. Ive never even heard of this stuff. Its pretty expensive (https://www.arbico-organics.com/product/5119/caterpillar-control-deciduous-fruit-trees). I may consider giving it a try if things dont calm down in the near future.
Yeah very interesting read. Thank you for the feedback. I wish us luck man. Sprayed with pyrethrin just out of desperation.
 

thumper60

Well-Known Member
Just went and cut in two spots on one of the branches. I fed the fishing line up and down the hole to see how far it went so I knew where to cut. I made a two inch incision about 5-6 inches above and below the hole. No worm, and it really didnt look like much in terms of damage on the inside, especially the top cut, which appeared to look how its supposed to. Ill continue to try this on branches with holes that have more frass coming out as time goes on. I want to save chopping entire branches for a last resort. I also hear that frass sends a signal to other borers that "this is my spot!", and might try to harvest and spread around to other plants. But im seeing such a tiny amount of it that it might not be enough to even work.



Sorry to hear that dude. Mother nature is vicious and favors no man. We do our best with what we have and thats all that matters I suppose. Its likely that anything we could use to eradicate any of these guys effectively would hand in hand wipe out the plants too. I guess looking to the future, figuring out the pests habits and life cycle could be valuable information. If they're overwintering in the soil (like many others I love no-till and renewable gardening practices), I certainly dont want this to become an annual thing. I will be doing the same thing with the frequent BT spraying and DE applications, If you end up getting a leg up on your situation id love to hear what helped. I know manual hunting and removal is one of the best ways to deal with cats/worms, but when they're invisible (kinda) that goes out the window..
If you start at the hole slice upward you can follow the trail they dont go up the center of the stem they eat the meat between the outer skin an the hollow center.
 

thumper60

Well-Known Member
I was definitely considering filling a dropper with BT, inserting and injecting directly into the holes. Since they already made their way all the way up and down I figure it might be tricky to get it to be as effective as if I did it when they first got in. Missed that window :wall:. It seems like the holes are becoming less active, so maybe this generation is getting close to being done.. Either way, my thought process is if their gonna be chewing out of the plant and the stalks are treated with BT it should still have an effect? I know there is a delay between ingestion and mortality, im just not sure how it would go if they eat the BT on their way out, cease feeding, and then pupate. Maybe the adult moth will die off?



Yeah man, this is some freak-show shit. It was like hell having to consider chopping branches even just to identify the species. Only the main stalk, and 2 main top branches have active holes, and if I were to cut just one that would be a third of the plant gone right there. Shes a big girl. I weighed in what I may lose towards to end of the season to chopping branches and concluded that ill just wait to see what happens since I eat shit with either option regardless.
Man I wish I could blame 2020, but last year I had one shitty plant that ended up getting hit by borers. It was wayyy later in the season though, like September all the way till chop. I only noticed one maybe two branches that ended up finishing fine but had rotted knuckles where it met the stalk. I was able to kill one of them when harvested. The stuff ive read says both that they'll stop late July to pupate overwinter, and that more generations will show up throughout the season making it harder for me to figure it all out. That might be the source of what im dealing with now though as that soil was composted near by (stalks and stems bagged up and thrown out). But then again, I had no problems prior to last year to begin with, only one plant is affected which was in the middle of a row of 3, and they showed up so much later in the season.
They dont come from a moth an they dont chew they way out, The bore straight up until stem is to small cat is to big. then they burrow down thur the main stem into the ground where they wait for next spring to hatch into a flying borer looks a lot like a bee. Google squash borer thats what you are dealing with. The damage is done once in the stock. If you see wilting on those branchs cut them off save yourself the pain later. I would cut now still got a couple weeks to heal an veg more.
 
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