To test for alkalinity: Put a few drops of cider vinegar to the soil. If it fizzes, it is alkaline. Use peat moss to reduce alkalinity.
Source: Reader's Digest 1001 Hints and Tips For Your Garden
By Robyn Fed from Hampton, TN
By testing your soil in your lawn every 3-4 years, you can keep on track if your lawn needs to have nitrogen added or not. Nitrogen is the key nutrient needed for a thick, green lawn.