Chris Jacobie - Soil Test 2021

[cjac9chris]

HISTORY

2021 will be my first full season caring about and for the lawn. I got interested in lawn care around June of 2020.

I’ve owned this house for 4 years. Until this past year, I hired the cheap mow and blow guys to bag clippings during the summer and pickup leaves in the fall. I irrigated for about 15 minutes (maybe .10" of water) when the yard looked like it might combust if I didn’t. No weed controls were used and I had a pretty big crabgrass infestation this year. Oh and I think the guys I hired might’ve sprayed some nitrogen-only liquid fert a couple times.

This year I put down various fertilizers based on marketing hype + local recommendations, tried my darnedest to irrigate 1" of water per week and mow regularly. I also did a Fall pre-emergent app.

SOIL

I didn’t trust my interpretation of the jar test. I went ahead and had Logan run a physical analysis report (attached.) It’s a “clay loam” in the backyard and a “silty clay loam” in the front.

The percolation test was interesting. In the first hour it drained 8.25”! I checked back about 30-40 minutes later and all the water was gone.

To check for compaction, I pushed a thin, metal marking flag into the ground around the front and back. I could only push it in about 4”.

So it drains super fast but is also possibly compacted? I’m confused.

THE LAWN

The lawn is about 700 sq. ft. in the front and 1200 sq. ft. in the back. It is currently St. Augustine of an unknown variety. There's also a temporary patch of annual ryegrass in the back and a big bare spot in the front.

I’m considering renovating the whole thing with Floratam St. Augustine.

MOWING PRACTICES

With the St. Augustine, I mow at 4” with a rotary mower and mulch the clippings back into the lawn. The annual ryegrass is getting mowed around 3”. Right now I’m mowing the ryegrass once every 5-10 days based on when it needs it and 1/3 rule.

The St. Augustine is currently dormant. During the summer I was mowing 1-2x per week, again based on when it needs it and 1/3 rule. My plan is to mow super often this year to try and keep the crabgrass in check.

IRRIGATION PRACTICES

I have a hose-end rotor sprinkler (Orbit H20-6.)

I base my watering amount on the ET data from Texas ET. The measuring station is about 10 minutes from here so it’s pretty accurate. Plus, I have my own rain gauge to compare their data too.

Right now I’m watering about once a month and in hottest part of the summer it’s 1-2 times per week.

I’m also going to put down a split-app of Hydretain every 6 weeks because we don’t get much rain here. (Only 22 in. last year and most of it out of season.) It also might help with the fast drainage too.

PEST ISSUES

I think I had chinch bug or grub damage in the hottest spot of the backyard last year but I don't know for sure. Could’ve well been a fungal issue as well.

Like I said, I had a big crabgrass infestation last year. I had to manually pull it because, as far as I know, you can’t spray St. Augustine for crabgrass because they’re both wide-bladed grass types. I just put down my pre-emergent (Sunniland’s Dithiopyr 0-0-7) last week as our soil temps crossed the 55* threshold. Hopefully that will help.

APPROACH

I would like the best approach, to address all deficiencies and I would prefer to try and keep things organic if at all possible. I currently have the following products and live in a major city so most things are available.

Organics

• Milo (6-4-0)

Synthetics

• Hi-Yield Iron Plus Soil Acidifier (11-0-0) (Ammonium Sulfate and Iron Oxide according to the label)

• Sunniland Professional Crabgrass Control Pre-Emergent (Dithiopyr + 0-0-7)

And without further ado, here are my lab results from Logan Labs. I had them do ammonium acetate testing since I’m on a lot of limestone. Also, I went ahead and did the physical analysis report since the jar test was a little fuzzy for me. The organic matter percentage differs between the soil report and the physical analysis. I tried to remove as much visible organic matter from the sample as possible but maybe that’s where the discrepancy is coming from?

Big thank you in advance! This forum rocks!!

Chris

TL:DR
This is my first ever soil test and my first full season of not neglecting my lawn. I want the best possible approach and to start trending in the right direction this year. I’ve attached both my soil reports and physical analysis reports from Logan Labs. Thanks!


Soil Test Results


Physical Test Results (Front)


Physical Test Results (Back)

[andy10917]

Please post a link to this posting in the Soil Test Interpretation Queue

[andy10917]

Oh Lord!!! After the Year 2020, we start 2021 with a strongly calcareous soil??

[cjac9chris]

Hahahaha it's South Texas. Good luck!

[andy10917]

No, I'm not confused by the calcareous soil - but how to explain it to others is really hard. You have so much Calcium running around that even with an Ammonium Acetate test, the results show very large shortages of many other nutrients. But they're not really shortages, and if you just convert the "negative numbers" you'll make things worse -- this is called "chasing the ratios".

Even the TEC (generally a good predictor of soil structure numbers) is severely inflated.

PS: you can't remove the Calcium. Ever.

Here's what really is going on, and what nutrients you should add to your soil:

You have good organic matter levels. Clay (which you have plenty of) and organic matter hold cations well - and almost all of your's is holding Calcium. The "shortages" of Magnesium and Potassium are not real and the raw numbers are OK.

And the Phosphorus numbers are fine (even on the high side).

Even in the micronutrients, most are OK - the only one that is very short is Iron -- and that is very hard to improve in a soil with a pH of around 8.0 (back to the Calcium problem as a cause).

So, here's the only thing you really *CAN* do. The use of Milorganite supplies Iron in a chelated state even at your pH. This chelated Iron aids color because it remains available significantly longer. I'd spend my money on Milrorganite at bag rate monthly. While this all probably sounds like a dead-end to you, it's not -- you can grow a very nice lawn on that soil, but it leaves few options for remediation.

I see you posted a lot of detail about weeds and irrigation, and the resulting challenges. These are not oil issues and not addressed here. I'd recommend posting them in the Warm-Season forum area when everyone comes out of hibernation in about a month.

[cjac9chris]

I've been using Milo exclusively on the annual rye and it's looking amazing. Plus, Milorganite is about the cheapest organic fert I've found per pound of N. So this sounds like a win to me. Sure, it's not as exciting as getting my Boron levels correct but it sure simplifies things and it's easy on the wallet. Thank you for your time!

[andy10917]

Sure, it's not as exciting as getting my Boron levels correct

Your Boron numbers are right where I want them - that happens 2-3X a year -- but on Numero Uno this yer

[MorpheusPA]

"So, here's the only thing you really *CAN* do."

He's so negative. I think he's having PTSD (Post-Trivialis Stress Disorder). I would have phrased it, "Here's the only thing I'd recommend, if you want to."

You can grow an absolutely lovely lawn on a calcium-heavy soil. Grasses don't mind, but may not (as described above very well) attain their best, darkest green colors. The Milorganite will help with that, and St. Aug isn't a terribly picky grass anyway.

You won't be able to grow blueberries very well, but neither can anybody else within fifty miles of you.

[cjac9chris]

Sure, it's not as exciting as getting my Boron levels correct

Your Boron numbers are right where I want them - that happens 2-3X a year -- but on Numero Uno this yer

I'll take it!

You can grow an absolutely lovely lawn on a calcium-heavy soil. Grasses don't mind, but may not (as described above very well) attain their best, darkest green colors. The Milorganite will help with that, and St. Aug isn't a terribly picky grass anyway.

Of course I'm not going to be able to lower that soil pH but I could spray with Ferrous Sulfate Heptahydrate at triple the rate. Maybe that's a post for somewhere else though.

https://turf.unl.edu/turfinfo/6-7-Iron-Chelates.pdf

https://aggie-horticulture.tamu.edu/pla ... /iron.html

[MorpheusPA]

I wouldn't go to triple the rate on St. Aug, it just won't require it. Most grasses really won't, although I might give a very slight nod to elite Kentucky bluegrass where a doubling might come in handy every now and again.

Supplying iron via foliar spray can work, but it's not the most efficient process and really only gives it the needs of a week or two during the active growth season. I've given up doing so except very late in the year when I get a lot of bang for the effort--November, mostly, as growth slows, sunlight weakens (so the created chlorophyll isn't destroyed quite as fast), and the color really stands out against the neighbors' yellowing lawns.

[cjac9chris]

I wouldn't go to triple the rate on St. Aug, it just won't require it. Most grasses really won't, although I might give a very slight nod to elite Kentucky bluegrass where a doubling might come in handy every now and again.

Supplying iron via foliar spray can work, but it's not the most efficient process and really only gives it the needs of a week or two during the active growth season. I've given up doing so except very late in the year when I get a lot of bang for the effort--November, mostly, as growth slows, sunlight weakens (so the created chlorophyll isn't destroyed quite as fast), and the color really stands out against the neighbors' yellowing lawns.