DocV Soil Test 2020

[DocV]

Thank you in advance for the help you can provide. I am a relatively new member and have read most of the articles (especially the soil series, great read), many posts and the amount of knowledge is outstanding. This is probably way more info than you need but I thought giving you as full a picture as possible would help in your analysis and recommendations. In April 2020 I had a soil test conducted by the University of TN Extension Office (included for whatever that is worth). Logan appears to be far superior in testing.

Logan Labs Report (samples taken at 4" depth)


UT Report (6" depth combining front/back lawns)


Front Lawn


Back Lawn


LOCATION: Brentwood, TN

AGE OF LAWN: 16 years old, established in 2004

SOIL COMPOSITION: 32% Sand/64% Silt/4% Clay with silt loam texture

GRASS: roughly 16,000 sq.ft. of mostly Turf Type Tall Fescue with 20-30% Bermudagrass. Mowed every 7 days at 4 inch height. The back and front lawns receive full sun most of the day. Minimal thatch (you can see the soil when parting the grass). Aerated yearly.

IRRIGATION: now 0.5" water, 2x/week via automated irrigation system. Previously under watered for years but roots are 4-6 inches deep.

ISSUES: Minimal weeds but invasive Bermudagrass from my neighbor's lawn. The color is lacking that deeper green but I suspect that is from low Fe.

HISTORY: For the previous 3 years I have had a lawncare company fertilize and weed control the lawn. The lawn looked ok but was lacking something and they would not treat for the invasive Bermudagrass. I decided this year to take that over so I could treat the lawn to suppress the Bermudagrass using the treatment regimen recommended by the University of Tennessee for controlling Bermudagrass in TTTF. The thought is to stress the Bermudagrass in late Spring as just comes out of dormancy, don't stress the TTTF in the heat of summer and stress the Bermudagrass as it goes into winter (herbicides are Fusilade II or Pylex in combination with triclopyr). I have 2 dogs.

TREATMENTS THIS YEAR:
March - Lesco 19-0-7 with Dimension (0.5 lb. N/1000 sqft)
April - Lesco 19-0-7 with Dimension (0.5 lb. N/1000 sqft, BioAdvanced Complete Insect Killer for grub control
May 5 - Fusilade II + triclopyr
May 23 - BLKH+3% fulvic acid and BLSC
May 29 - Fusilade II + triclopyr
June 12 - BLKH+3% fulvic and BLSC

EQUIPMENT: Echo RB60 spreader, FlowZone 4 gallon Tornado backpack sprayer with Teejet tips for foliar and soil application, soil probe

FUTURE TREATMENT PLAN:
July-November - app each month of BLKH+3% fulvic and BLSC
July - BioAdvanced Complete Insect Control
August - Pylex + triclopyr
Sept - Pylex + triclopyr and 1 lb. N/1000 sqft (product yet to be determined)
Oct - Pylex only and TTTF overseed (possibly try rhizomatous TTTF), fertilize with 1 lb. N/1000 sqft
Nov - 1 lb. N/1000 sqft (product yet to be determined)

GOALS: I would like a healthy green lawn. I am looking for the best approaches for optimizing the soil and the lawn because I believe good soil makes great grass. I have moderate experience applying fertilizers and herbicides. Thanks for all your help.

[andy10917]

Doc:

Very thorough profile of your scenario - thanks!!

While a first soil test outlining the differences in soils front-to-back can point out issues, your's doesn't show many differences and I think a single (mixed) test in the future is good enough.

Structurally, you've got a Loam soil there with a bit more silt than normal, but there are no issues (I'd take it!!). The OM% numbers hover just to either side of the "Excellent" 5% number. This is what I like to see.

In the cations, there is a bit of an excess of Calcium. There is little you can do about most excesses, but adjust your practices to accommodate reality. Your scenario is showing a somewhat high pH due to the Calcium surplus. Oh well, we look for ways to deal with it - it's not a showstopper. However, I would NOT adjust the Magnesium shortage (small) because the reward/risk isn't there - we don't want to push the pH higher. We'll deal with the Potassium. Get and apply Sulfate of Potassium ("SOP", 0-0-50) at 2 lbs/K to both lawns monthly.

Phosphorus is fine (actually at luxury levels).

Iron is very good, but not available at your pH level. If color is one of your concerns, then look into foliar FAS applications or using Milorganite as your Nitrogen source (monthly at bag rate). If you're not crazy about Milorganite searches, then use your own Nitrogen source selection and do the FAS foliar route.

In the micro's, Boron and Zinc are short - do you want to address them this year?

Overall, this is a workable soil that you should look at as requiring an alternate approach, but there are no barriers to success. Adapt and work with what you have, and things will come around...

[DocV]

Hi Andy,

Wow, thanks for the quick response and on a holiday nonetheless. It's good to see that the soil is workable. I do believe in using what you have. I was concerned that my Ca levels were so high I would need to order the ammonium acetate test. I do wish to address the B and Zn deficiency.

Have a Happy 4th!

[andy10917]

Get Twenty Mule Team laundry soap (for Boron) from the grocery store, and Zinc Sulfate from EBAY/Amazon. Apply at 3 tablespoons/K each as outlined in the Micronutrient Application Guide, every 60 days.

[DocV]

Hi Andy,

I assume I can spray on the K, B and Zn at the same rates you outlined?

Additionally is there a good source for the level of micros in the soil needed for turf grasses? The only sources I have been able to find are from 1998 from the University of Washington (https://archive.lib.msu.edu/tic/holen/a ... 89sep3.pdf) and this article from a turfgrass magazine https://www.google.com/url?sa=t&rct=j&q ... KOMDbTn3yh.

What are good sources for understanding given your level of a macro or micro in the soil (assuming a deficiency), the amount of you should add or perhaps you could point me to a good agronomy book for turfgrasses.

[andy10917]

I assume I can spray on the K, B and Zn at the same rates you outlined?

No. The quantities of nutrient that can be applied using a foliar application are a small fraction of what can be applied directly to the soil. All nutrients listed are for quantities using a spreader.

What are good sources for understanding given your level of a macro or micro in the soil (assuming a deficiency), the amount of you should add or perhaps you could point me to a good agronomy book for turfgrasses.

I don't know of any that would be appropriate for residential lawns. Most are written for golf courses, agriculture and/or sports fields. Those aren't anywhere close to the soils of residential land.

I don't publish a list of what all of my spreadsheets use for target rates, because many of my rates are ratios of one nutrient to another, and not hard and fast reference numbers. They take into account both the synergistic and antagonistic reactions identified in Mulder's Chart.

Using rates that are designed for surface applications to do foliar or tilled soil is a major mistake in my opinion.

[DocV]

Hopefully I am not being a pest with all my questions. I am a microbiologist/molecular biologist by training and have decided to focus my interests in turf agronomy so this is all fascinating to me.

I assumed the rates of application would not be the same given the differences in the efficiency of foliar vs. root uptake, but I thought I would ask since I am relatively new to turfgrass biology.

Thanks for the reference to Mulder's Chart. It is very helpful in understanding the interplay between nutrients. I have been looking at the ratios of other macro utilization to N utilization and stumbled upon the PACE Turf Climate Appraisal spreadsheet (https://www.paceturf.org/journal/climate) and MLSN.

[DocV]

Hi Andy,

Just saw the 2016 discussion on these topics. Thanks for all your help.

[DocV]

Andy,

Should I try to lower the pH slightly by applying elemental S?

[andy10917]

Doc:

If it worked, I would have told you about it. It doesn't work, causes a Yoyo effect, and is a fool's errand.