Q: We have mushrooms growing in our lawn. They look like those sold at the store. Can they be eaten? Where did they come from?

A: In medieval times people believed mushrooms sprang up in rings where fairies danced at night. The ancient Romans thought they appeared from earth after lightning struck. The Artecs of Mexico credited them with magical powers.

Some may be eaten. But specialists sound a word of caution about the gathering of wild mushrooms, however. Many poisonous species grow side by side with edible specimens, and there is no simple test to distinguish one from the other.

By far the best policy is not to eat them. Individuals react very differently to the toxic chemicals produced by mushrooms.

One person may eat a certain mushroom with no ill effects while another may have severe nausea and intestinal distress. rally under certain conditions. Many types are important to the environment because they aid in decomposition of organic debris such as leaves, grass and trees. Without them, this debris would accumulate and cause serious problems.

Q: Last fall we had to prune a limb from our white dogwood tree. The limb was approximately two inches in diameter. After pruning we applied a wound dressing to the cut. The sap did not seep through last fall. This spring the sap dripped continually from the end of the limb. We reapplied the wound dressing. It did not stop the sap. Can you suggest anything that will help?

A: The dogwood, like grape vines and certain maples, is a heavy bleeder. The bleeding does little or no harm: it is mostly water. It starts after the tree breaks dormancy in the spring and continues until the tree is well covered with foliage and growth slows down somewhat. If there is plenty of water available in the soil, bleeding will be heavier than when the soil is deficient in moisture.

Application of a wound dressing will not stop bleeding. In fact, the wound dressing will not adhere if applied to the wood when it is wet.

If your tree is weakened, the best thing you can do for it is water it thoroughly during prolonged dry weather, and fertilize it in late November or early December when it becomes dormant.