Discussion in 'Pesticide & Herbicide Application' started by rvsuper, Sep 27, 2002.

  1. rvsuper

    rvsuper Senior Member
    Posts: 930

    How soon do you put down Pre-M for lawns? Do I do it this fall or should I put it down next spring?
  2. tremor

    tremor LawnSite Bronze Member
    Posts: 1,476


    Apply Pre-M about 2 weeks prior to the anticipated date that the tagreted weed is expected to germinate.

    That would obviously vary a lot depending on where you live & the weeds you're interested in controlling.

    Can you list the weeds & your USDA growing zone?

  3. greenman

    greenman LawnSite Addict
    Posts: 1,405

    Actually, both fall and spring. The fall pre-m is to prevemt the cool season weeds from germinating and the spring pre-m application is to prevent the warm-season weeds (crabgrass is one ex.) from germinating. Timing is the key.
  4. Aughfully expensive to treat cool season weeds.

    You could treat 98% of the cool season weeds for under $0.30/M, heck go one better straight 2,4-D $0.18/M

    As apposed to about $1.25/M

    Feb to mid March is a good time for my zone.
  5. Double post.

    They got the "reply w/quote" and the "edit" buttons reversed on this forum.
  6. greenngrow

    greenngrow LawnSite Senior Member
    Posts: 403

    If you have a big problem with chickweed, henbit and other winter annuals. Then a Pre-m down in in the fall will help out. I only do it for new customers that I picked mid year. It helps build customer relations.
  7. greenman

    greenman LawnSite Addict
    Posts: 1,405

    i guess I don't understand your post LGF about treating cool-season weeds. Are u saying not to put down fall pre-m?

    Fall pre-m will keep (most of it, nothing is 100%) henbit,dandelion, some daisies, some ivies, wild onion and garlic (just to name a few) from coming up.All of these aren't really a problem though because they can be treated with postemergent, but why wait u til they germinate? We have a problem here with poa anna, 2,4-D will not control this grass but a pre-m in the fall will prevent most of it from coming up in the early spring. Pre-m applied in early spring will keep most broadleaf weeds from germinating, as well as nutsedge, dallis grass, crabgrass,quackgrass. Two pre-m in the spring can be applied to take care of the grassy weeds. Early spring and late spring.
    If I am in error about this, someone let me know. Though I do have some bit of experience, I am here to learn form the best.
  8. Yes 1 app of pre-em in the Spring only. Demension.

    You are talking about 3 apps of pre-em.........Isn't that excesive? Is that even legal?

    Practicing IPM is not to over do it. 3 apps of pre-em is over doing it. IMO

    Poa anna (sp) is not a problem here, much less I have never seen it.

    Confront, 2,4-D, and other post herbs will do a much better job controling pests, than 3 apps of a pre-em. Don't you still do a post app(s)?

    I have never had a pre-em control Nut Sedge.

    Not to change you progam to much but you are at a $3.75 cost per 1000 sq/ft and I bet you have more applications to do. You still have your fert and post apps to do.

    Weeds are going to germinate, which is the best to to treat and avoid problems?
  9. greenman

    greenman LawnSite Addict
    Posts: 1,405

    Never thought about 3 apps of pre-m being too much. I have never done the 2 in the spring, just heard about in on here. Around here we always do a fall pre-m to control the poa anna and wild onions and garlic. then a spring pre-m is done for the crabgrass and such. Any weeds that do come up are controlled with post-m. Poa anna is a problem here in the bermuda lawns only. I have never seen it in zoysia and st.auggie. alot of the lawns here are bermuda.:(
    As for as the nutsedge, it usually comes up in heavily irrigated areas and beds, and they are fairly hard to control.

    Fall pre-m may not be necessary where cool-season grassses are grown.
  10. tremor

    tremor LawnSite Bronze Member
    Posts: 1,476

    I think Larry (LGF) & I are in a similar situation agronomically. Our cool season Blues & Ryes are NOT very agressive survivors of the summer. Especially this year. Yet they are prolific in the fall.

    The opposite is true to our south, where the turf does well during the warm summer months, then as it cools, weeds take over the slowed down turf.

    Interesting. Up here, guys like Larry & I only rarely consider a fall preemergent. The only times it's done here is for Poa. And even then, most guys are scared that the Pre will interfere with fall seeding.

    I've said for years that I should try it for Poa. But I never do it because sometrhing always needs seeding.

    Hey Larry, maybe we ARE the dummies on this one.
    Pre-M 3.3EC for Poa would be applied at 1.3-1.8 oz. If we split the difference & say 1.5 oz & the stuff sells for $48.00 gallon then at $.57/M a fall Pre-M is cheaper than spraying Threeway for weeds and then having the client cancel because of Poa.

    Perhaps up our way, the shadey lawns could be spring seeded. Then skip the spring Pre. There won't be crabgrass in the shade anyway. The do a fall Pre for the Poa.

    Not much of the perennial Poa actually survived this year. And I haven't seen a lot of it yet this fall.

    For the record. Three Pre-M's per year is like a wet dream for us pesticide sales guys. And not only would Poa disappear, but so would Bent Grass.
    Of course we'd also never be able to seed again.


    How do you guys reestablish turf when needed? Vegitative? Sod?


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