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Merit and watering in

Discussion in 'Pesticide & Herbicide Application' started by turfsolutions, May 20, 2005.

  1. turfsolutions

    turfsolutions LawnSite Senior Member
    Messages: 854

    I applied Merit to most of my grub control customers 7-14 days ago. At the time the weather was calling for a chance of thunderstorms for 3-4 nights. Well we did not get any rain. Here in southeast Pa. it has been cool, but dry. Today finally we are getting a good soaking.

    Oh crystal ball, will my Merit work if it had not been watered in for as many as 1-2 weeks after application? Keep in mind the average temps have been 70 high 50 low. What do you guys think and is anyone in my boat?
  2. lawnservice

    lawnservice LawnSite Senior Member
    Messages: 589

    we apply merit from mid june thru july, typically the hottest, dryest time of season. I know for sure many folks do not water it in even though our instructions say too and we have not had any failure with the product.
    our merit apps are on a 21-3-8 50%ppscu fert
  3. Runner

    Runner LawnSite Fanatic
    Messages: 13,497

    It will be fine. A little early,... but it'll be alright.
  4. marko

    marko LawnSite Senior Member
    Messages: 963

    I agree, too early of an application. I shoot for getting it down by July 4th. I have been told that it is important to get it watered in within 24 hors after application due to degradation by the sun. I also discharged the clippings for a month when I was bagging to keep the chemical in the turf area.
  5. tocs93

    tocs93 LawnSite Member
    Messages: 37

    Use Mach 2 next year and you won't have to worry about it being watered in so soon after application.
  6. turfsolutions

    turfsolutions LawnSite Senior Member
    Messages: 854

    As far as too early, for this area, better to be too early than too late. I have been applying Merit for 10 years at this time with little to no failure. It might be to early for other parts of the country, but grubs were pretty bad here last fall and most anticipate it being worse this year. I have already seen 1 instance of grub damage on a new lawn this year. Very early for grub damage.

    As for Mach, I know some people that had a lot of grub damage after using it last year. I'll stick with what has worked for me.

    Thanks for the replies, I will rest easier now.
  7. marko

    marko LawnSite Senior Member
    Messages: 963

    Spring grub damage is common and 99% of the time not a problem as they do little eating, preparing to emerge from the ground around June. After the eggs hatch in late July/Aug this is where the big feeding starts as they are preparing to move down into the soil to overwinter. If you apply in July, water in, the pesticide is in the soil and into the roots and available to them as they move up to the root zone and start feeding. You are not going to control grubs in the spring with Merit when they are this large. Applying towards the beginning of May gives you 2 less months coverage when you need it, later in the year. Plus with the product sitting for 2 weeks w/ no water, there is a big question of the degradation that might have taken place. Best bet is July 4th, dont catch clippings for a month, and water in within 24 hours. Here is a Quote from Bayers website:
    Lawn Applications to Control White Grubs
    Conventional insecticides rarely give good control of these lawn pests. Grubs are soil inhabitants that live and feed in areas where pesticides have trouble reaching. For this reason it is best to use Merit insecticides for white grubs. Merit Granular has two characteristics that help achieve control of such pests: super long residual and systemic action. Merit Insecticides are available in granular formulation as well as wettable powder concentrate formulation: Merit .5G Insecticide Granules and Merit 75% Concentrate.

    Season long control is a great advantage when fighting this lawn pest but the product can possibly break down under severe conditions such as water and extreme temperatures. In most cases the summer/fall application of Merit systemic insecticide will do the trick. If you live in an area where infestations are stubborn or difficult to control or if extremes in rainfall or temperatures might affect the insecticide, an extra application in late spring could be quite beneficial.

    Merit contains an active ingredient that can give season long control of white grubs with a single application. You should apply Merit insecticides no sooner than mid July and no later than early August. Check with your local extension office to see if this time table is different in your area.
    Merit is a systemic insecticide, which means that the material is taken up by the root system of the plant. As pests feed on the plant, they are ingesting your insecticide. Using a product with systemic action means that you do not have to depend on the targeted pest to come into contact with applied products. This action also aids in the long residual of the product because insecticides that are inside the plant and its roots cannot be harmed as much by the sun or other elements.
  8. turfsolutions

    turfsolutions LawnSite Senior Member
    Messages: 854

    Provided by Rutgers University out of southern New Jersey:

    Chemical control – preventive: With preventive control,
    an insecticide with a long residual in the soil is applied as
    insurance, before a possible grub population develops.
    Insecticides used for preventive grub treatments are the
    neonicotinoid imidacloprid (Merit®, Advanced Lawn
    Season-Long Grub Control) and the molt-accelerating
    compound halofenozide (MACH 2®, GrubEX). Due to
    their long residual, imidacloprid and halofenozide can be
    applied as early as May and June, respectively. If applied
    that early, various other insect pests may also be controlled
    (billbugs, annual bluegrass weevil, greenbugs;

    Last year was our wettest year in the last 50 years. I applied Merit at the end of May with no failure come fall when the grubs were feasting. In this area, late May early June is the time to apply.
  9. marko

    marko LawnSite Senior Member
    Messages: 963

    Provided by the manufacturer:

    Plus the 24 hour watering in was delayed. Good luck.
  10. turfsurfer

    turfsurfer LawnSite Senior Member
    Messages: 364

    Some experts, notably Dr Dave Shetlar from OSU propose a mid may application of Merit here in Ohio to control not only grubs but also Chinch bug and billbug using the multiple target principle. Possible because of the long residuals provided by these newer products compared to the older grub controls.

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