crabgrass issue

Darryl G

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You may be getting a false reading due to electrical properties of the application you did. I highly doubt it's a true reading. BTW I was a chemist and then an environmental scientist/hydrogeologist for 15 years combined and have run all sorts of laboratory and field instruments. I've learned to never ever make decisions without confirmation of any analytical parameters.

We used to take the pH of soil samples by adding them to a measured volume of water and using a pH meter to analyze the liquid. That was the ASTM method.

Bottom line, I have serious doubts that is the pH of your soil. As far as your shallow well goes, if you're in an area with a lot of limestone it could be alkaline for sure but not that high I don't think. Your water quality certainly could be having an adverse effect on your lawn though if it's high in dissolved minerals and salts. Stains are usually from dissolved iron (red/tan/brown) and manganese (grey/black/dark brown). So you may want to have your water tested too. Look around for reduced price testing through your local health department or state regulatory agency or other program. Maybe even the agricultural extension. You can also buy colorometric strips for many tests too, just like use for testing pool water.
 

corvairbob

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I doubt if the crabgrass pre-emergent is changing the pH of the soil, at least not that much.

It takes huge amounts of lime to change the pH from 9 to 7 and most of the ingredients of a bag of fertilizer/herbicides are inert.

thanks something is changing it. tomorrow i will test the sprinkler water just to see. out tap water tests with this tester at 7 and i asked the city and they said they try to keep it at 7. we get our water from lake michigan so it is relatively soft water. no one on our city water uses any treatments. and we do not get water stains in the washer or toilets so using our water to calibrate this is good not the best but good.

so if my well water test with this tester to be around 7 then i have to say for now the crabgrass preventer is causing the change for the moment. also tomorrow i will test the neighbors yard where my sprinklers water there yard and if they have lower ph then that about nails it down to the preventer as it is melting into the soil. thanks
 

corvairbob

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You may be getting a false reading due to electrical properties of the application you did. I highly doubt it's a true reading. BTW I was a chemist and then an environmental scientist/hydrogeologist for 15 years combined and have run all sorts of laboratory and field instruments. I've learned to never ever make decisions without confirmation of any analytical parameters.

We used to take the pH of soil samples by adding them to a measured volume of water and using a pH meter to analyze the liquid. That was the ASTM method.

Bottom line, I have serious doubts that is the pH of your soil. As far as your shallow well goes, if you're in an area with a lot of limestone it could be alkaline for sure but not that high I don't think. Your water quality certainly could be having an adverse effect on your lawn though if it's high in dissolved minerals and salts. Stains are usually from dissolved iron (red/tan/brown) and manganese (grey/black/dark brown). So you may want to have your water tested too. Look around for reduced price testing through your local health department or state regulatory agency or other program. Maybe even the agricultural extension. You can also buy colorometric strips for many tests too, just like use for testing pool water.

thanks i tend to agree with false readings due to the preventer now dissolving and not in the ret of the close area i did not apply it. i have about a spoon full left in the bag so i will put that in some water and see what happens. if it turns out about the same then i have the reason. and i will post that test.
 

corvairbob

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thanks i tend to agree with false readings due to the preventer now dissolving and not in the ret of the close area i did not apply it. i have about a spoon full left in the bag so i will put that in some water and see what happens. if it turns out about the same then i have the reason. and i will post that test.

ok put a few pellets of the crabgrass preventer in a bowl and water and as the pellets dissolved the meter show going to 6 and lower so now i have to measure the well water tomorrow i will get a sample as today it is like 30 deg out and i'm not freeing to get the sample. but then i will know if the well is turning the ground sweet. thanks
 

Darryl G

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It takes huge amounts of lime to change the pH from 9 to 7 and most of the ingredients of a bag of fertilizer/herbicides are inert.
No amount of lime would change the pH from 9 to 7...wrong direction. Lime raises pH.
 

cpurvis

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No amount of lime would change the pH from 9 to 7...wrong direction. Lime raises pH.

If you could take lime OUT of the soil it would....and you'd have to take out a lot.
 
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