markexpress
Active Member
Posted this in Outdoor, no replies. Hopefully you guys can help.
In my area, I have some serious pests that I deal with, the worst one is the beetle borer. See pictures attached. I need some help/advice in dealing with this nemesis.
First of, here a description of the pest and what it does. Starting with second or third week of June, these small worms appear that are looking for a plant host. Once it finds the plant it likes, it will climb the stem - first it will climb all the way up and then back down - to assess the size of the plant and the stem width. If the stem is too small or too hardy it will leave. Otherwise, once the worm determines the height of the plant it will then borrow a hole inside the stem about half-way up, and the worm then proceeds with eating the inside of the stem - ALWAYS going up the plant stem first and then after the stem becomes too thin on the top, it goes down the plant. Once the worm reaches the bottom, it migrates to some part of the stem where it awaits for the plant to grow more and then burrows inside the side branches stems. As a result, the centre of the stem becomes hollow, and some plants can even collapse or die. Typically the worm enters in the middle of the plant. Often more than one worm can enter the same plant during the season. The time frame for the worm's burrowing activity is early-mid June to the end of July. After which time the worm lays eggs inside the stem and transforms first into a fat black grub-like creature, then eventually becoming a small black beetle. Sometime in early August the beetle makes an exit hole and leaves the plant, until the next year. All this information is based from my observations, none of it is made up and nothing is assumed.
So why do these worms/beetles target cannabis plants? Well, I found out why this past summer. Turns out there is a species of native weeds that are endemic to this part of Ontario (don't ask which part), which the beetles typically target. The weed's stem is almost exactly the same, both on appearance and inside. I found the same holes and same results inside. EXCEPT, those weeds are dealing fine with these intruders and the weeds dont collapse or die.
I tried some sprays, powder and pellets to no success against this smart pest. I tried applying stuff to the bottom of the stem, around the stem, and to a certain degree they repel this pest but eventually the beetle worm finds its way up the plant sometimes. On average I end up having 40-60% of my small number of plants infected with this bug. The ONLY thing that had some level of success was using Bonide Annual Tree and Shrub Insect Control (see Amazon link: http://www.amazon.com/Bonide-Annual-Insect-Control-Gallon/dp/B002ITL19A/ ). Its very effective for the roots. At the end of the season I pulled out the plants, and the ones I applied that chemical to had ZERO creatures of any kind in the roots. Just soil. Not even one soil worm. Have not noticed the effect on the smoke (I never smoked a bud in my life, just taking my customer's word for it). The problem is that its a chemical that it taken up by the roots of the plant, and takes at least 1-2 weeks to take effect for the stems and the leaves. Sometimes I noticed the bugs attempted to burrow inside the stem, only to abandon their attempt and leave. Victory. I saw the partial entrance holes, proving that this chemical had some effect. Sometimes the results were not-so-good, and actually did more damage: the worm burrowed its way in, only to die inside the stem a few inches into its climb. The plant's stem then collapses at that point where the bug died - typically half-way or two-thirds of the way up.
So how does this bug affect the plant? Well, munching the centre of the inner stem does not often kill the plant (only about 25% of plants die), but it causes long-term damage. The plants end up being shorter, with smaller buds and take longer time to finish flowering. Last year I had 8 of G13 Pineapple Express plants. Four were infected, two died from half-way up (ended up branching out and getting only half the yield of other plants), while the other two infected plants didn't show signs of problems until in mid September, when I harvested the other plants but these two took an extra two weeks to flower and the buds were a bit smaller - but smoke-wise it was just as good.
Anyways, if anyone can recommend me anything I would really appreciate it. This will be my last year doing a guerilla grow, from which point I will either retire from growing or get a license.
PICTURES of the beetle borer worm I took after dissecting the stem of an infected plant.
In my area, I have some serious pests that I deal with, the worst one is the beetle borer. See pictures attached. I need some help/advice in dealing with this nemesis.
First of, here a description of the pest and what it does. Starting with second or third week of June, these small worms appear that are looking for a plant host. Once it finds the plant it likes, it will climb the stem - first it will climb all the way up and then back down - to assess the size of the plant and the stem width. If the stem is too small or too hardy it will leave. Otherwise, once the worm determines the height of the plant it will then borrow a hole inside the stem about half-way up, and the worm then proceeds with eating the inside of the stem - ALWAYS going up the plant stem first and then after the stem becomes too thin on the top, it goes down the plant. Once the worm reaches the bottom, it migrates to some part of the stem where it awaits for the plant to grow more and then burrows inside the side branches stems. As a result, the centre of the stem becomes hollow, and some plants can even collapse or die. Typically the worm enters in the middle of the plant. Often more than one worm can enter the same plant during the season. The time frame for the worm's burrowing activity is early-mid June to the end of July. After which time the worm lays eggs inside the stem and transforms first into a fat black grub-like creature, then eventually becoming a small black beetle. Sometime in early August the beetle makes an exit hole and leaves the plant, until the next year. All this information is based from my observations, none of it is made up and nothing is assumed.
So why do these worms/beetles target cannabis plants? Well, I found out why this past summer. Turns out there is a species of native weeds that are endemic to this part of Ontario (don't ask which part), which the beetles typically target. The weed's stem is almost exactly the same, both on appearance and inside. I found the same holes and same results inside. EXCEPT, those weeds are dealing fine with these intruders and the weeds dont collapse or die.
I tried some sprays, powder and pellets to no success against this smart pest. I tried applying stuff to the bottom of the stem, around the stem, and to a certain degree they repel this pest but eventually the beetle worm finds its way up the plant sometimes. On average I end up having 40-60% of my small number of plants infected with this bug. The ONLY thing that had some level of success was using Bonide Annual Tree and Shrub Insect Control (see Amazon link: http://www.amazon.com/Bonide-Annual-Insect-Control-Gallon/dp/B002ITL19A/ ). Its very effective for the roots. At the end of the season I pulled out the plants, and the ones I applied that chemical to had ZERO creatures of any kind in the roots. Just soil. Not even one soil worm. Have not noticed the effect on the smoke (I never smoked a bud in my life, just taking my customer's word for it). The problem is that its a chemical that it taken up by the roots of the plant, and takes at least 1-2 weeks to take effect for the stems and the leaves. Sometimes I noticed the bugs attempted to burrow inside the stem, only to abandon their attempt and leave. Victory. I saw the partial entrance holes, proving that this chemical had some effect. Sometimes the results were not-so-good, and actually did more damage: the worm burrowed its way in, only to die inside the stem a few inches into its climb. The plant's stem then collapses at that point where the bug died - typically half-way or two-thirds of the way up.
So how does this bug affect the plant? Well, munching the centre of the inner stem does not often kill the plant (only about 25% of plants die), but it causes long-term damage. The plants end up being shorter, with smaller buds and take longer time to finish flowering. Last year I had 8 of G13 Pineapple Express plants. Four were infected, two died from half-way up (ended up branching out and getting only half the yield of other plants), while the other two infected plants didn't show signs of problems until in mid September, when I harvested the other plants but these two took an extra two weeks to flower and the buds were a bit smaller - but smoke-wise it was just as good.
Anyways, if anyone can recommend me anything I would really appreciate it. This will be my last year doing a guerilla grow, from which point I will either retire from growing or get a license.
PICTURES of the beetle borer worm I took after dissecting the stem of an infected plant.
See above. I believe that once the worm in comfortable inside the plant, its almost impossible to get it out without causing heavy damage to the plant. As I said earlier, these worms climb up first (always!), so injecting BTi will not help (it will drip down), and my attempts to inject liquids into stems last year were futile in results. Worm must be removed from the plant within the first 2-4 hours after it entered the hole (using a thin long grass or wire), by entering a thin long durable object inside and gently pressing it until it reaches the end. Then remove it, repeat if necessary after a 2 minute wait. If the worm has not been in the hole for more than 2-4 hours, it climbs out. The longer it spends inside, the less likely it will come out.
