I always wonder if a person could send their soil samples to another state's Extension service? I'm assuming that a soil test done in Maine, say, using Ohio soil would yield the same results as the same tests done in Ohio.

I downloaded a soil test application from our local extension Co-Op at URI (Universtity of Rhode Island), and was surprised to discover the mailing address is UMass Soil Test Lab in Amherst, MA. There doesn't appear to be any regulations restricting gardeners from other states using their services.

Here is a link that might be useful: UMass Soil Testing

Thankyou! I downloaded and printed the instructions and order form. I'd like to do the testing soon, so I know what to do in spring.

Even though the Ohio State University USDA Cooperative Extension Service does not do soil testing they still should be able to provide you with places that do.

The UW-Madison operates a "Soil and Plant Analysis Lab," see UWLAB.Soils.Wisc.edu/Madison/. Last time I checked prices, it cost $20.00 for a general test, "basic potting mix," for pH, potassium, phosphorous, nitrogen, calcium, & magnesium.