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marlin304

Planting trees soil test interpretation

marlin304
9 years ago

Hello, I planted a number of trees this fall before the cold set in. One is a bur oak about 8 feet tall had been grown in a pot . Four are red maples (red rocket X 3, october glory X 1 about 4-5 feet tall in smart pots) Soil test by the bur oak site revealed ph 7.0 Phosphorus (p) 41 and potassium(k) 192
The site by the red maples was ph 6.2 P 15 k 212.
The organic matter was 2% for each site. The ag extension office commented that overall soil looked good for these trees but recommended adding phosphorus at 75lbs per acre. I tested 10 locations on property and phosphorus was low at each site.
What does everyone here think? I am located in western Illinois zone 5b/ 6a border.
Thanks!

Comments (10)

  • marlin304
    Original Author
    9 years ago

    Picture of trees planted.

  • Toronado3800 Zone 6 St Louis
    9 years ago

    Nice trees. How big of a yard do you have and do you have a way of adding this phosphorous? Also are there any sneaky ways of adding it or your organic matter? For example I do not bag my clippings and use my mower to recycle my leaves. Doing so makes it easier on me AND increases my organic matter.

    If this phosphorous project is manageable go for it. I'd just hate to think you are going to get the trees used to 1 kind of soil then keep having to do this for them for the next 100 years.

  • whaas_5a
    9 years ago

    No need to add anything to your soil for any tree ever. Only time it makes sense is for small shrubs, perennials and fruit/vegetable gardening.

    The ag ext recommendations are for agricultural sites.

    Where are the trees from by the way?

  • marlin304
    Original Author
    9 years ago

    Trees are from Sooner Plant Farm. I've ordered a lot of trees from them and they are always in great condition.
    Prior to the test I was worried about the soil ph for the red maples since I know they like slightly acidic soil but 6.1 should be good. I was also worried about chlorosis with the oak due to alkaline ph but ph 7.0 should be ok from what i've read. Would anyone suggest using a fertilizer with higher phosphorus in the spring? It does seem that there recommendation was for ag sites. I haven't read much about these trees having problems from low phosphorous. Usually pH , iron, manganese issues from the little bit of research I did.

  • whaas_5a
    9 years ago

    Is your phosphorous 41 ppm? If so that is actually high.

    Mine is 16 ppm and have 100s of different species growing on my lot so it really doesn't matter.

    You are correct ph is the only item you need to be concerned with when it comes to plant that are sensative, Red Maple being one of them.

    I figured they were from Sooner. Their prices are extraordinary but they usually have nice trees.

    Have fun with your new plants. Keep an eye on the Red Rocket's width. I got a Super Sonic and Red Rocket and both where almost 6' wide after 3 seasons so my plants where incorrectly labeled.

  • marlin304
    Original Author
    9 years ago

    Yes they are not cheap with larger trees especially after you add shipping. The phosphorus was in lbs/acre. After a quick search on google I found that lbs/acre divided by 2 gets you parts per million approximately. So the phosphorous by my bur oak would be around 20 ppm and by the red maple would be 8 ppm. I'll keep an eye on the width.

  • edlincoln
    9 years ago

    What is the soil consistency? Sandy, loamy, or clay?

    You could use Jobs tree Spikes. Or you could use Biotone Root Starter...supposedly it has symbiotic soil bacteria and fungi. Who knows if that actually helps, but it sounds good.

    Right now the most important thing for you to do, though, is to water the trees before the soil freezes.

  • marlin304
    Original Author
    9 years ago

    I guess you'd say my soil is part clay/part loam. I did water them in pretty good buy may do it one more time as the temps are supposed to warm up above freezing next weekend.

  • edlincoln
    9 years ago

    Soil temperature lags behind air temperature...it doesn't freeze until some time after the air temperature goes below freezing...but it takes a while to defrost as well. My soil isn't yet frozen in 6. I would think a clay/loam mix would hold water a while, so you would have to watch for over-watering.

  • wisconsitom
    9 years ago

    I'd recommend only that you begin to mulch in leaves, small twigs, and other small-scale tree debris. All of your readings are well within acceptability for those species. BTW, it's pH, not ph or Ph. Just saying, if you want to look like you know what you're talking about!

    2% organic matter is a bit low. 5% is held as the standard, keeping in mind this is going to fluctuate over time. But just a little higher would be better. If you do happen to note chlorosis on your rubrum maples, soil sulfur is not an unreasonable answer, being easily spread over the soil surface periodically. Your soil will always buffer it back to whatever the pH was initially, but it's not difficult to redo the sulfur. Plus, if you would happen to boost organic matter a bit, that alone might obviate the need for any other pH treatment.

    +oM