Question
we have an 8 year old sunset maple tree in our yard and this spring it started to drip sap.  the leaves are covered, as is all the plants underneath the tree.  The first thing I noticed was what I thought were tons of small flys in the tree. they are still there, I guess they are not houseflys but seem to be some kind of smallish bee.  Now I've noticed all the sap all over everything and some of the new branches (twigs) look 'gnarled' and bumpy. This is a pretty tree and a major shade provider for our above ground pool.  Can you please tell me what I need to do?

Answer
These insects are sucking the sap and secreting a substance called honeydew. Honeydew is high in sugar content and sticky and usually a has a sooty mold growing on the honeydew. Control the insects and the sap will go away.
Treat the tree with an insecticide called Bayer Advanced Tree and Scrub Insect Control. This is applied to the soil around the tree and the roots will carry it to the twigs and foliage and when the insects feed they are killed. This product will last for the whole season. Check with your local garden type store for this product. Here is a a web link to this product. http://www.bayeradvanced.com/tree-shrub-care/products/12-month-tree-shrub-insect