Q: The concrete steps at my house are moldy and kind of green on the risers, except where I applied a concrete sealer. I did it badly, so you can see areas that look like drips. How can I safely clean ...

Q: I have planted lots of seeds in trays this spring, ready for potting on and planting out as the temperatures warm. However, I've noticed green mold forming on the soil in a number of the trays.

Add Yahoo as a preferred source to see more of our stories on Google. Question: Green mold has started to grow on the trunks of several different trees in my yard. Some of the trees have dead branches ...