BOlson32's Soil Test 2021

[bolson32]

Hey Gang,

Big thanks for all of the help you've already given me over the past few months. Really glad I found this community, it's been real painful not being able to do much during the summer drought up here in Minnesota, but I got my soil test and I'm ready to rock when the timing is right.

Lawn Size: ~60,000sq ft(1.5ish acres). I generally treat for about 50-52k for weeds/fert as some areas I just don't care about, like the ditch.

Location: Minnesota, East Twin Cities Metro

Soil Type: Managed to dig up my septic compliance inspection from a few years ago with the soil sample down to 65". I'm not sure if this is indicative of the entire property, but I have seen a good amount of topsoil everywhere. That said, the soil is acting much more "clayey" than silty loam right now. I'm not sure if that's due to an imbalance, or just years of compaction or other things. But especially given this drought, it's ROCK hard.

Depth" Soils Encountered
0-10 10YR 4/2 Silt Loam
10-24 10YR 4/3 Silt Loam
29-37 10YR 3/4 Sandy Loam
37-54 10YR 4/4 Medium Sand (Dry)
54-65 10YR 3/6 Loamy Sand With Gravel

Existing Habits: No irrigation, she's too big. I mow weekly at 4", but I've mowed once in the past 8 weeks. Have had zero rain. Fert/Weed plan is in progress

Equipment Available: 85lb Spreader, 25gallon boom sprayer, Sub Compact tractor and mower

Goals: My primary goal is to have a good lawn, with good soil. Right now about half of my lawn is really solid(due to hydroseeding the front half, before we bought the property), and the other half is pretty meh. The soil just feels HARD, like concrete when it's dry, and honestly still pretty hard when it's wet. Honestly, I've got 6-month-old twin boys, and by the time they're running around. I'd just really like a lawn that's nice to walk and play on.

As for how much time I'd like to invest, the perfectionist in me would love to get this thing to 99.9%. That said, given the aforementioned time constraints, I'm going to have to follow the 90:10 rule and work on the heavy hitters that get me 90% of the way there.

[bolson32]

Did a little further reading on Andy's Soil Management II article and wondering...maybe I don't actually have clay-type soil, based on the TEC of 7.77.

I guess I misunderstood that clay usually has the most compaction issues, but perhaps some loams can even have it worse. Either way, I have pretty bad compaction issues, and that's probably the biggest thing I'd like to alleviate. This house was built on an old cornfield. So, hopefully the soil is salvageable.

[andy10917]

OK, first things first - make sure to post a link to this thread into the Soil Test Interpretation Queue.

Now, I have to make a WTH comment. That is completely the opposite of what I was expecting to see. This is going to take a rather long post, and I'll get to it as soon as your turn comes up.

[bolson32]

Haha, oh boy. That doesn't sound good!

And sorry about that, I didn't see the queue so I wasn't sure it was still necessary. But, done!

[andy10917]

Alright, this is pretty tough to figure out - there are many unusual situations here...

The first is that it is pretty unusual to see an acidic soil (pH = 5.9) in the Twin Cities area. In fact, the area is so prone to alkaline soils and even calcareous soils that we recommend Ammonium Acetate testing as a first step to avoid retesting costs. The "AA" on the results page indicated you did that, but the results show that you're nowhere near calcareous levels, almost by definition. When repeating your soil test next year, use the standard test and not the AA test, please.

The septic inspection results seem to confirm the TEC results that you've got a silty loam or sandy loam soil. That brings into question why you feel the soil has a clay base. When I get that indication from owners, I tend to look at the Calcium/Magnesium ratio, as a high Magnesium fraction can make a tight/hard soil impression. Unfortunately, the AA test (by design) suppresses excess Calcium and/or Magnesium. But the pH report seems to indicate that excess Magnesium/Calcium wouldn't be present if the pH is below 7.0. Therefore, I have no explanation for the perceived soil hardness.

So, on to the specifics...

Your test results indicate a soil that is just below the threshold for a Loam soil (those start at TEC = 8). A Sandy Loam is most likely. It is acidic at a pH of 5.9. The OM% at 3.85 indicates that the organic matter is at the higher end of the mediocre range.

In the cations, Calcium and Potassium are short. In the anions, Phosphorus is also very short. When both Phosphorus and Potassium are short, we turn to balanced fertilizers like 10-10-10, 19-19-19, etc to minimize costs and efforts. But with 60K of lawn, applying 10 lbs/K of 10-10-10 monthly is going to cost real money. More on that later.

The Iron number is somewhat low, and that can affect color. Down the road, we'll address that as we will for the micronutrients - I'd like to see a standard test instead of the AA test first, and your limits on time and cost say we can't address everything at the same time.

I'd recommend picking a subsection of the 60K lawns, and concentrate on that for now. See how it goes and reacts. Maybe just the Front Yard at first? You can also experiment with the BLSC soil conditioner in an area and see if it loosens up the soil, and move on from there, depending on results.

Locate a balanced fertilizer and post the NPK for application rates. Do as often as budget and costs permit, up to once per month except July and August.

Retest with the standard Test next year, and we'll work with those more-appropriate numbers and plan with you to extend the subsection applications and add to the other areas if things permit.

[bolson32]

Yea, I was as surprised as you! I uploaded a few pictures of some hard pan where the the grass has died. One of them had been driven over a handful of times while I built my garage last summer, and it's been REALLY dry. But the rest of the lawn "feels" similar. If that makes any sense.

The other picture is the underside of some sod I ripped up after it rained. You can see that that section seems to have much better tilth. And I guess the eye test seems to almost confirm sandy loam.

I think some BLSC/BLKH could potentially help a ton. I'll try and find a local, suitable fertilizer tomorrow and post it for app rates. Fleet farm might be the go-to with Superior of I can catch it on sale for $7.99 a bag for 25lbs.

[bolson32]

[ken-n-nancy]

That soil just looks excruciatingly dry to me.

[bolson32]

That soil just looks excruciatingly dry to me.

It absolutely is, we're in a full-on drought up here. That said, even when it rains, it doesn't loosen up at all. You could step right in those after an inch of rain and barely leave shoe prints. I can't imagine that's "normal" even for sandy loam right? I know there isn't any grass currently growing there, which doesn't help. The the tilth of the soil, at least near the surface is pretty poor.

@Andy,

What would the application rate be on something like this?

https://www.spikesfeed.com/award-19-19- ... 0-lbs.html

[andy10917]

About 5 lbs/K, applied monthly as specified above (not applied July 1 - August 15).

[bolson32]

Cool, I think I'll stick to mostly full apps. I found a feedmill that has 50lb bags of 19-19-19 for $20. If I cut my tree rows out I can get by with 50k sq ft. That means $100+tax per application.

When you say monthly, how long are you thinking? Indefinitely? Or more like Aug, Sept, Oct, Nov and retest next spring?

[andy10917]

When you say monthly, how long are you thinking? Indefinitely? Or more like Aug, Sept, Oct, Nov and retest next spring?

Yup, mid-August until the grass stops growing.

[bolson32]

Since we've finally gotten some rain. This is what I'm talking about when I say the ground is hard and compacted. We've gotten 1.5" of rain in the past 36 hours, almost 2.5" since Thursday. Would you consider this normal for a sandy loam? Obviously this is a bare spot,, but It's pretty similar where the grass is as well.

https://photos.app.goo.gl/STyYqrTArej5wYKt7

[MorpheusPA]

You can come in now. COME IN, I SAID.

Yes, that's a solid soil. With the rain you got, that's...really solid. Can you push a screwdriver into it? Your Ca:Mg ratio isn't THAT whacked, so...have you tried soil conditioner? That can help loosen up a soil, as can application of organic material in that specific spot as a top dress.

[bolson32]

I have not tried the soil conditioner, I think that's my next step though. Frankly I was thinking of just hitting it with the KH and SC a few times over the next year.

Since I've got so much area, a dial and spray isn't really that feasible. Can I spray it with my boom sprayer as long as I time it around some rain?

As for an organic app, would you have a specific one that might help better than the rest? And a rate?