Available Water Setting

@Modawg2k Did your mason jar ever settle ? I just realize I think I’ve been getting fooled. When I shine a light behind what I thought was mostly clay, I think it’s completely unsettled water. It probably is Sandy Loam after all, but it’s been maybe 3 weeks and the top section doesn’t settle. I wonder if I should just pull the cap off and let it evaporate?

I have officially gone too deep in…

yea, on that triangle, I agree.mmwhich puts you back to Avondale clay loam, possibly…
Sounds like if you want your awc to be dead on balls accurate, you will have to measure it by hand.

Nonsense,science is fun…

But I think that is clay, just the proportions could be smaller.

I have already run into this. I computed my awc by hand which was a mother bitch and not worth the .01 awc I saved.

I can try to dig up the links I followed…but you need access to some graduated cylinders…it’s probably easier to send your soil off to a lab for $40.

Your top layer should be water. What type of detergent did you use?


@Modawg2k. Cascade Complete dishwasher detergent. It doesn’t say anything about suds free, but I figured that was common. Maybe not? What did you use and how long did it take to settle?

@plainsane. That sounds pretty painful. I may try another mason jar test, or just wing it. Early on I saw my lawn getting watered more frequently than common convention around here, and I wasn’t cycle soaking, which is common. Switching to Clay Loam made that all fall in line. I have a feeling that the right answer for me is somewhere in the middle.

Mine is just normal Finish powder detergent. My picture shows my dirt at like 3 days. Was our Cascade powder or gel?

Powder. I plan to try again this weekend. I’ll see what I can find.

A teaspoon of table salt can be used as the dispersing agent in the Mason jar test instead of dish washing detergent. The clay layer may take days to settle and some of the smallest clay particles may remain in permanent suspension and not settle out at all. I left a jar sitting for three weeks and the clay never completely settled. This test is an estimation, but still provides enough usable information to determine soil textures.

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@sunny. Good to know. I’ll try using salt instead!