Grass is yellow where stumps were ground
Q: We purchased our home last July and had several trees cut down. The stumps and roots were ground and then we laid fresh bermuda sod. Overall the grass is doing great for it’s first season but I have a few areas where the trees used to be that look totally different from the surrounding areas. The grass is thinner and has more of a yellowish color than the deeper green around it.
A: An excellent question with a simple answer. The chips and stump grindings that were inevitably left in the soil are food for fungi and bacteria that are naturally present. In order to digest wood chips these microorganisms require nitrogen. They are very efficient at finding and using any nitrogen they can get their hands on.
Your bermuda grass also needs nitrogen to grow. But the soil microorganisms are so efficient, they rob nitrogen from the grass. This makes the grass slightly yellow.
The solution is simple, scatter a pound of 10-10-10 per every 100 square feet of affected grass. Do it now in mid July and again in late August. If the grass seems yellow next May, repeat the application alongside your regular fertilization.