Soil analysis - need your help on this one

Discussion in 'Pesticide & Herbicide Application' started by David W, Jul 25, 2007.

  1. David W

    David W LawnSite Senior Member
    Posts: 282

    I just received these results back from A & L Labs in Memephis. I have researched the previous threads on this subject but still would like to have you guys feedback and comments.

    The lawn was just renovated last fall, with new topsoil brought in and graded etc, and seeding with a fescue blend. It looked great coming up and again this spring but is really starting to thin out.

    These results are above me as I am still learning and this is new to me.

    Would appreciate your help.
     

    Attached Files:

  2. muddstopper

    muddstopper LawnSite Silver Member
    Posts: 2,342

    Looking at the nutrient levels, you would think that this lawn has everything it needs. There are a couple of things out of wack. Excessive high zinc levels are tieing up the P, even tho P is listed as high. K levels are excellent but,,, Sodium is higher than K. when Na levels get 1/10th of 1% higher than K, the plants will take up Na instead of K. For this reason, K levels should be pushed up to around 6 or 7 percent saturation levels. Calcium and magnesium are border line and can be pushed up some to help with the Na problem. Sulfur is listed at 100lbs per acre, this can also be pushed up to around 160lbs and will help with the ph raisieng effect of the lime application.

    Just wondering, did the top soil come from a cow pasture? That might explain the high Na levels. Are high zinc levels common in your area, or is it possible that you might have pulled a sample close to galvinized pipe buried in the ground, or used a galvinized piece of pipe to pull the cores?
     
  3. David W

    David W LawnSite Senior Member
    Posts: 282

    Muddstopper, thanks for the breakdown. Your posts have been a great deal of help on this site.

    The topsoil came a outift who sifts topsoil and mixs in some compost. It is the best and richest topsoil we have around that is sifted. Awesome soil to work with, like powder.

    Galvinized piple thery could very legitamte as the samples were pulled close to where a chain link fence was removed last fall during the renovation.

    What do you think the best plan of attack would be in adjusting the ph this fall? The lawn needs o be re-seeded this fall but didn't know if I should hold off on adding ammoniun sulfate or sulfer when we core aerate or go ahead and apply it now.
     
  4. muddstopper

    muddstopper LawnSite Silver Member
    Posts: 2,342

    David, the chain link fence is probably the reason for the zinc. Did you pull more than one core. If the fence is the reason for the zinc levels, once you get away from that specific area, the zinc levels should be a lot lower. I also suspect that the compost that is being mixed with the soil is where the Na is coming from. Good news, if I am right about the salt source, is that the salt will eventually leach away.

    As for the sulfur and the ph, you can start applying it now, I suggest maybe using SOP to raise K levels as well as the sulfur levels and I would also go ahead and broadcast a little lime for the calcium and magnesium. Your ph is 7.4, that isnt all that high for Fescue, not perfect, but grass will grow in that range. I suspect that as the sodium leaches away, that the sulfur in the fertilizer will be all that is needed to get the ph down into the high 6's. Depending on what the base soil is under that topsoil. Test the soil again next year, staying away form the chain link fence area, so you can monitor the na levels. Pull your soil test at the same time each year. Nutrient levels vary according to the time of year and are usually higher in the spring than in the summer because of organic matter breakdown. Taking test at random times doesnt give you a good indication of how well your soil is actually performing. You can test spring, summer or fall, just do it at the same time each time you test.
     
  5. muddstopper

    muddstopper LawnSite Silver Member
    Posts: 2,342

    David, I made a mistake, I went and looked at the test results again and realized I had read the calcium levels wrong. Leave off the lime, even tho it would help lower the Na levels. Use SOP and elemental sulfur instead.
     
  6. rcreech

    rcreech Sponsor
    Male, from OHIO
    Posts: 6,072

    Mudstopper,

    Why recommend adding SOP as a S source when the K levels are already high especailly when SOP won't change pH much at all?

    DavidW,

    Looking at this soil test....the only minor issue is the higher pH. As Mudstopper says you can add elemental S, but if this was mine, I wouldn't do anything at all.

    Macro and Micro's look good.

    As for as the Na and Zn, I wouldn't worry about them too much. Very little you can do about them and neither will be an issue in growing a good lawn. I have never know anyone to get too excited about micros unless they are defecient (which yours is not).

    Best to work with your lab, local extension or University on recommedations as they can get a little crazy on here at times.
     
  7. treemonkey

    treemonkey LawnSite Member
    Posts: 178

    It's easy to miss the "forest for the trees" when doing diagnostics. How many times someone has come up to me and asked "what's that bug, disease, or other thingy over there right in front of your eyes"? How often we pursue an assumption due to "blinders".

    Did you use good seed cultivars?
    Did the area get over-compacted during prep?
    What's the watering history?
    Is there a disease - symptoms tied to hot weather?
    What's the N application history?
    Did you ask the homeowner if they are doing anything to the lawn - maybe holding car shows there every weekend? A goat herd?

    Muddstopper, sounds like you need to submit a "sticky" on proper sampling techniques for everyone.
     
  8. muddstopper

    muddstopper LawnSite Silver Member
    Posts: 2,342

    Tree, I think I have a link somewhere that goes into pretty good detail about taking a soil sample, I will look it up and maybe the powers that be can stick it at the top.

    Recreech, My only reason for suggesting addition K is because of the Na levels. Most plants dont distinguse between Na and K when it come to nutrient uptake and will take up which ever is in the most abundance. His Na levels are higher than his K levels. I suggested Sop because it also contains sulfur. In his case he could also use Kmag or Sulpomag and raise his magnesium and K saturation levels and reduce the Na saturation levels at the same time, and probably also reduce his ph some. (not talking big changes here)

    Recreech, before we get into another long discussion, there are usually two trains of thought when it comes to fertilizer use. One group believes in supplying the minimum fertilizer amount to just meet the needs of the plant that is growing at that particular time. Farmers growing crops look at the cost of the fertilizers verses the amount of crops they can harvest and decide if the extra cost is worth the extra fertilizer. The other group believes in building the nutrient levels in the soil and letting the soil feed the plant. I subscribe to the latter and I believe you subscribe to the former and that is where our disagreements on fertilization begins. I am not saying you are wrong or right, there are very many people that believe as you do and many testing companies that provide fertilizer recommendations based on those beliefs. There are also many companies and individuals that believe as I do and their fertility approach is going to be somewhat different that what you are accustomed to seeing. There is also lots of research that supports each method. To me, turf is a high value crop, but it is usually limited in the acreage it covers so the extra cost of feeding and balanceing the soil isnt that great. I can also see where someone that is growing hundreds of acres of corn or other cash crops might not see the need to build the nutrient levels in their soil. Some times the extra production of the crop doesnt support the cost of the fertilizers, and sometimes it takes several years before the extra nutrients pay off. In this situation, just applying the minimum amounts to produce a crop makes the most economical sense. At any rate, I will try to answer your questions the best I can so maybe you can understand the reasons behind my suggestions, lets just try to keep the conversation civil.
     
  9. rcreech

    rcreech Sponsor
    Male, from OHIO
    Posts: 6,072

    Mudstopper,

    I agree! I do apologize for last time...but it was frustrating (as I am sure it is with you also) when I read something and it doesn't agree at all with the way I was taught at the University level.

    You are a good man! BTW....that was a pretty good catch on the Zn and the fence. Moral of the story...Results are only as good as the samples you pull.

    I might also add that when pulling soil samples pull the grass and thatch layer out of the sample.

    Anyway...I do agree with you one a few things but as you say..we both have our ways.

    As far as fert and farming we actually have to manage fertilizer much more and apply much, much more then the turf industry. When "taking off" a crop you remove large amounts of fertilizer (especially P and K) due to the crop removal. Annually I apply about 150# of 18-46-0 and 250# of 0-0-60. This is what we call a buildup, which we are actully putting on more then the crop needs to get it into the "maintenance level". Anything over the maintenance level is treated more as a "piggy bank" and then if we have a bad year (like this one) we don't have to put on as much the next year.
    On a lawn typically very little added fert is needed, unless the clippings are being removed. I have not pulled a lot of soil samples from lawns...but almost all of the ones I have seen never need hardly any fert and pH is always high.

    So I guess I don't get too excited about pulling soil samples from existing lawns. Now, if trying to diagnose a lawn issue that is one of the first things I would do.
    I just apply a good SCU with Fe that contains lower levels of P and K. Works great on the 240 lawns I maintain!
     
  10. muddstopper

    muddstopper LawnSite Silver Member
    Posts: 2,342

    Recreech, I am sure you take samples at least every couple of years for your crops, do you ever set down and compare some of the older test results to some of the later samples you have on hand? ( I'm betting you do).This would be a very good indicator on how well you are manageing your nutrient levels. I dont know how much corn you remove from your fields each year, but building your nutrient levels as you describe is one way to insure that there is adequant nutrients in reserve for when the plant can use it the most. It can be hard to time correctly fertilizer applications , especially when the corn starts getting head high, so followup applications can sometimes be impossible, or at least not cost effective to attemp. It is also easy to see where you would apply much more ferts in a crop removal situation, the crops are nutrients bound up in the plant form and removal of the crops takes the nutrients with it. Where as on lawns, once you get the nutrient levels correct, all it should take is a minimal amount of fert to replace the ones lost from the natural leaching processes.

    I will make one suggestion about your Dap applications, and its based on a Tennessee Valley Authority (TVA) study that was done in the late 1950. It was found that at higher ph ranges that MAP for phosphate will stay available a little longer than the DAP. That same study also concluded that other P sources, ie., rock phosphate, 0/46/0, and 0/20/0, would tie up in as little as 8 weeks in the best of conditions and as fast as 4 weeks in bad growing conditions, yet the DAP and MAP would continue to be available the entire growing season. Just something for you to think about since you already have high Ph ranges.
     

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