meat thermometer or http://www.greencastonline.com/tools/SoilTempMaps.aspx

Out of curiosity, what are you going to do when you find out the soil temp?

Seems to me there's a website that is uncanny accurate.

It seems accurate, thanks for the tip!

I was really just curious, for now, how it relates to the actual air temp but now that I know it's that easy I'll use that to time my fertilizer apps & get a better idea of when I should expect the bermuda to green up. I can also see myself using it to estimate crabgrass germination start & stop times for the year. In drier years, I imagine the soil would heat faster & they would pop earlier, but I have no basis for that wild guess.