Merit drench for Jap Beetles

Discussion in 'Pesticide & Herbicide Application' started by Lbilawncare, Jan 26, 2008.

  1. Lbilawncare

    Lbilawncare LawnSite Bronze Member
    Messages: 1,120

    Does anyone use Merit as a soil drench japanese beetle "preventative"? If so, is it worth the cost and what rate did you use? I realize the beetles will still munch the leaves a bit, but I'm comparing the effectiveness to spraying after activity has begun. Thanks !
  2. Whitey4

    Whitey4 LawnSite Silver Member
    Messages: 2,448

    Geeze, I hate using the word "drench". Too many home owners did just that and now Merit is restricted here... it showed up in some wells. I don't think any chemical should be used as a "preventative". Using Merit should be based on a grub count in a sq foot of turf.

    Besides that, the larvae that is about to come up through the frost line soon has overwintered. These mature larvae are much harder to kill than newly hatched ones are. If they are Japanese beetles, and not another type, milky spore will wipe them out with a spring app. Using Merit on them might only make the eggs they lay this summer more pesticide resistant. The best time for treatment is after they laid their eggs, and the immature larvae hatch.

    When beetles are in their adult stage and flying, they may not have even come up from the turf you want to treat. Japanese beetles will fly considerable distances for their favorite vegitation. Since the Europen Chaffer and Oriental beetles don't eat in the adult, winged instar, they are likely hatched from closeby. They are only flying to mate and lay eggs.

    While milky spore is expensive, it is very safe compared to using a chemical application in the spring, when rain will leach it much faster through the soil. And Jap. beetles can't develop a resistance to it. It is extremely effective, but only on Japanese beetles, no other type.

    You would still have to treat their favorite vegitation like rose bushes and rasberry plants, and trap baits placed well away from those targets of the beetle work well in reducing the entire area's population. Get the adults before they lay. Problem with the hormone based bags is that they have to be emptied frequently. It's sort of nasty, and many home owners aren't willing to stay on top of it.

    LIBERTYLANDSCAPING LawnSite Bronze Member
    from Indiana
    Messages: 1,283

    Soil drench IS a great way to control jap. beatle, as well as other damage on ornamental (scale, bagworms, etc.) The other upside to it is you don't have the problem with killing off insects that prey on Mites, like you do with a foliar spray.

    Using bags is a "garden center" control mentality that is scoffed at by most land grant universities. They will tell you you may well attract many more beatles onto your properties with these, than would normally be there (as they will fly for many miles) Milky Spore is expensive, hocus pokus crap.
  4. Russ

    Russ LawnSite Senior Member
    Messages: 540

    NEVER EVER USE PHEROMONE TRAPS Unless you are pi$$ed at everyone in the neighborhood. It is well documented that they are not capable of killing the number of beetles they attract.

    Yes we have used soil drenches as well as injections with mixed results on Lindens, Cherry, Plum, Roses (bout 200 high value hybrids) Birch, Bayberry. The trick is to get the product into the leaf before pest emergent and while we didn't see a significant reduction of damage most of the customers were very pleased by the applications. In areas where a foliage spray is not possible we still make ground as well as vascular applications. When a drench or injection is made at the right time combined with a foilage spray just prior to beetle emergence we have had excellent results. We have achieved an 80-90% reduction to Lindens when trees in adjoining properties were devastated. We believe this is because the initial emerged beetles were killed on our plants while at the neighboring properties the beetles released the pheromone that says HAY THEIR IS FOOD AND SEX HERE. As to the rates check here I guess what I'm saying is that drenches and injection can increase plant protection when properly timed however they are (for us) only another tool and are not for us a replacement for the foliage spray.
  5. tremor

    tremor LawnSite Bronze Member
    Messages: 1,476

    Systemic insecticides can also be delivered right into the vascular system via the trunk. If using a Wedgle or dilling holes is of concern (is with me) then you might try PentraBark. Treat only the trunk from the 5' down to the flare. Imidacloprid is still slow. Depending on conditions it can take a while to cause knock down.

    Actually, Imidacloprid is weak on adult scarab beetles under the best of conditions.

    Watch for the new & improved Safari label some time this summer. Combined with PentraBark there is no quicker, easier or more effective way to treat even large specimens without concern for off-target sprays or soil drenches. New Yorkers will predictably be waiting a while longer than everyone else.

    Safari & PentraBark is already approved for Emerald Ash Borers in those states so afflicted.
  6. Russ

    Russ LawnSite Senior Member
    Messages: 540

    Tremor Good to see ya on here

    I have no experience with PentraBark but have heard rumors it will kill grass and can discolor the bark. Any truth to that?
  7. Whitey4

    Whitey4 LawnSite Silver Member
    Messages: 2,448

    First, it is the use of the word drenching I don't like. I know that this treatment has it's place. Secondly, milky spore DOES work! The key thing is that the soil temp has to be at 70 degrees of higher... which is a problem in the midwest perhaps. Back in the late sixties, Long Island had a virtual plague of Japenese beetles. What wiped them out? Virtually every property was treated with mikly spore. In two years, the population had dropped to very tolerable levels. It works, and it's not "hokus pokus". It won't work if the population is small however. The spores need a sufficient food source to be effective.

    I had a friend in Wisconsin... she was growing rasberries on a small farm. The plants were getting completely destoyed. She went through all the ground and foliar treatments there were, but still the damage ruined her crop. She did all her local cooperative suggested. She ended up buying about 25 ferimone traps, and placed them at her back forty... about 500 yards away from her rasberries. It took her two years, but she knocked the local population down by about 90%. No adults to lay eggs, no grubs. I certainly would not suggest the use of traps unless as a last resort, and never on a small property. For her, it was traps or give up on that cash crop.
  8. tremor

    tremor LawnSite Bronze Member
    Messages: 1,476

    Hey Russ,

    I still poke my nose in once in a while. There is significant entertainment value at times that is just irresistible. :rolleyes:

    All surfactants have the potential to burn turf that is under drought stress. However we're not treating turf with this application. A low pressure (hand-can) treatment of the trunk is all that's needed. Slight turf overspray should be avoided (label?) but doesn't pose a significant risk to turf health under the conditions present when these treatments are likely to be made.

    Discoloration of the bark? This rumor is 100% Hogwash started & perpetuated by a company with a stake in a competitive delivery system. We have California Oaks that were trialed with up to 25 bark treatments in a single season with no injury or discoloration (Agrifos + Pentrabark for SOD). Email me for the straight dope if you want it.

    Here in New England Agrifos & Pentrabark are already used widely for Beech Decline & I've never observed any discoloration. I have seen Beeches killed by secondary infections via injection holes so this new technology has significant value to conscientious arborists.

    Silver Maples that are treated with Pentrabark might demonstrate a minor & temporary lightning of bark just after treatment but it's not damaging & goes away pretty quickly. No other tree has demonstrated this.
  9. Whitey4

    Whitey4 LawnSite Silver Member
    Messages: 2,448

    Glad I could entertain you.
  10. tremor

    tremor LawnSite Bronze Member
    Messages: 1,476

    That wasn't a shot at you Whitey. You've been asking good questions & learning which is why this forum was originally concieved. More power to you. Stick around long enough & you'll notice that there is a "roll" like waves on the beach. There are three phases.

    Running away all burned out

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