Yet Another Jar Soil Test Help Thread

I’m attempting to setup a flex daily schedule for St Augustine grass, but not sure how to interpret this jar soil test. I think my soil type is 50% mocha latte and 50% oreo cookie blizzard.

I took samples from my yard down to 6" in 2 zones, prepped them in separate bins (removed debris / sifted) and then filled each jar to 1/3 capacity. Then I added 1 tablespoon of dishwasher to each jar and filled with water leaving 1" at top. I shook for 5 min and then let them sit. The clarity of the water is unchanged after 24hrs. It resembles the bottom layer of muck in a pond and I can’t see any change in light if I put a flashlight directly behind the jar. The soil is all or mostly suspended in water.

USDA soil data says my area is fine sand with 0.08 water capacity at 0-6" (grass) and .11 at 0-40" (trees/shrubs). However, it’s a new development on old farmland south of Tampa FL. They built up the entire phase with trucked in fill dirt from an unknown source and then graded to address flooding. The USDA soil data for the top layer of my yard is unlikely to be accurate.

Wow, that is strange that there is zero separation at all. I’m not a soil expert by any means, but in your hand, that looks VERY silty loam to me. Note that these values pulled from an ag page are inches per foot, Rachio is inches per inch, so divide by 12. Isn’t too far off of what soil survey shows. Even trucked in, chances are it could be similar soil makeup…

Sandy loams, fine sandy loams - 1.25 - 1.75

Very fine sandy loams, loams, silt loams - 1.50 - 2.30

I think you’re right. I did the same test minus the soap and after 2 hours it looks close to 30% sand 70% silt. I’ll give it a day or 2 for clay, but given what’s left it can’t be much. The triangle says it’s “silt loam”.

I guess the original soap I used reacted badly. I appreciate the help.

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