Northern Guys - what are you using for your late fall app?

Discussion in 'Fertilizer Application' started by DA Quality Lawn & YS, Sep 18, 2012.

  1. lazyike

    lazyike LawnSite Senior Member
    Posts: 257


    Yes but we are doing that app on irrigated lawns... On our dry lawns we are putting it down at a rate of .45# per 1000. With urea we have more of an issue with heat and not so much dry conditions, With the cooler days and longer nights we are seeing no burning. Urea will be used up by the lawns in 3 to 4 weeks giving the roots the nitrogen they need to "bulk up" before the ground freezes.
     
  2. Smallaxe

    Smallaxe LawnSite Fanatic
    Posts: 10,080

    See, that is where the traditional wisdom is a lie... I don't see any fertilizer breaking down into useable form and bulking up the plant in the next 3-4 weeks of this dry ground... it goes against everything we know and have experienced in the fert industry over the past 50 years...
     
  3. Smallaxe

    Smallaxe LawnSite Fanatic
    Posts: 10,080

    Does this mean that it makes sense to apply N in the winter, because most of it may stabilize in the frozen turf??? But we don't want a fresh supply of N as soon as the plants break dormancy in the Spring...
    That is one of the issues of cool-season grasses having the ability to put down roots w/out the waste of topgrowth energy... anhydrous ammonia is fine for corn, but not for turf... :)
     
  4. Skipster

    Skipster LawnSite Bronze Member
    Posts: 1,074

    Hang on there, Tex!! You're missing the boat on the N issue. Do we want a supply of N as soon as plants break dormancy? YES!!!

    You say you're railing against "conventional wisdom," but you're using such "wisdom" in thinking that N is necessarily antagonistic to root growth. Nothing could be further from the truth! N is needed by all plant tissues. High N applications don't even harm root growth (so long as sufficient moisture is present). I think people get this idea from N driving top growth more than it would drive root growth. But, applying more N won't slow roots down -- they'll grow at the same pace. It's just that you'll haveto mow more while its happening.

    The tilth that you keep talking about is more of a soil physical property thing and is important in allowing aeration and water infiltration and drainage in the soil, which promote the biological processes of the N cycle. Humus has a lot of CE sites and holds water well, but is mostly brrken down (definition of humus) and doesn't contribute much chemical fertility.

    Again, having available N in the soil at dormancy break will not "burn out" roots or carbohydrate reserves. Remember the 16 essential plant nutrients. N is one of them. N is a critical component of the chlorophyll molecule. If we don't have much of it in the spring, we can't produce the carbohydrates needed to replace those lost due to winter respiration.

    If you trying to best set up a turfgrass plant for success as it comes out of dormancy, why would you withhold a nutrient it needs for survival?
     
  5. lazyike

    lazyike LawnSite Senior Member
    Posts: 257

    I will grantee you that come spring these lawns will be the first to "green up" and come out of dormancy, I also have noticed that in these lawns they handle the winter better than the next. Dry or not there is still microbial activity in the lawns and the grass will uptake the nitrogen, results will not be seen this fall because there is not enough moisture to have that just fertilized look, but you can bet that the result will be seen in the spring.
     
  6. DA Quality Lawn & YS

    DA Quality Lawn & YS LawnSite Fanatic
    Posts: 8,873

    Ike - your logic sounds good but the urea has to get rained in at some point right?
    Right now we have no rain in the 10 day forecast, who knows we may ride out a bunch of fall with no rain whatsoever. Won't urea volatize over time if it doesn't get rained in?
     
  7. mikesturf

    mikesturf LawnSite Senior Member
    Posts: 793


    When you use Milorganite, are you basically applying this solely for the benefits of an early spring green up and absolutely no late fall green up? I'm under the impression that Milorganite is slower release and needs higher soil temps than what is found during a late fall "winterizer" application.
     
  8. Smallaxe

    Smallaxe LawnSite Fanatic
    Posts: 10,080

    Here is a CentroWisco site that has a couple of cautionary remarks about early Spring N apps... I'll find some more...

    http://outagamie.uwex.edu/files/2010/05/Lawn-Care-Tips-2.pdf

    ... Never fertilize in April through early May; you will be fertilizing the weeds that are starting to sprout instead of the lawn

    ... Returning grass clippings to the turf does not contribute to thatch. Early spring fertilization (April & May), fertilizing four times a year, over watering and pesticide use contributes to thatch. Core aeration in the months of May or September (when the turf is actively growing) reduces thatch build-up. Excess thatch cultures several turf diseases.
     
  9. Smallaxe

    Smallaxe LawnSite Fanatic
    Posts: 10,080

    Keep in mind that this area is a couple months ahead of CentroWisco, so the definitions of Winter and Early Spring are @ different months... enjoy...

    http://turfdisease.osu.edu/turf-disease-updates/benefits-late-fall-fertilization

    "... root and shoot activity and plant respiration rates increase during the late winter and early spring, plant carbohydrate content generally decreases. This decline may be quite significant when the turf receives an early season (February-April) nitrogen application, as compared to grass that has not been fertilized since the previous fall. The rapid decline occurs because carbohydrates are needed to support the increased shoot growth resulting from nitrogen applications made early in the season. Conversely, the more slowly-growing, late-season-fertilized turfgrass plants may possess a larger carbohydrate pool during the spring period. As will be discussed later, the process of spring root production can benefit from this greater concentration of carbohydrates from a late-season application. ...

    ...The true advantage that late-season fertilization provides to turfgrass root growth is realized during the following spring. It has been shown that the root growth of turf fertilized during the late-winter/early spring declines soon after nitrogen application (3 & 5). Conversely, turf fertilized using the late- season concept becomes green early and rapidly, without the need for an early spring nitrogen application, and root growth continues at a maximum rate. It appears that the excessive shoot growth encouraged by early spring nitrogen applications utilizes carbohydrates that may otherwise be used for growing roots ..."


    It would actually be informative to read that entire section about root growth, as I only highlighted the relevant point...
     
  10. Smallaxe

    Smallaxe LawnSite Fanatic
    Posts: 10,080

    Dry or not, the grass will still uptake the N... and that is a good thing,,, even if it is true???

    I agree that it will be green in the Spring, because there may be some moisture added to the soil over the next 5 months and the ET is way down... but that doesn't prove that N added now does anything for the turf now...

    In fact, my August applications are still sitting on the ground to a large extent,,, and I would be considered a 'ripoff' by charging clients for another .75 lbs of N...
    You think that the seriousness of this drought situation doesn't apply to you...

    You would do well to read this entire article so that you can make sense of what you are seeing as a result of your barren land applications... :)

    http://turfdisease.osu.edu/turf-disease-updates/benefits-late-fall-fertilization
     

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