Q.Red maple not leafing out in Virginia
I planted a red maple in my backyard 10 years ago and it has never had a problem – it was started as a whip by a local Arbor Day group. I also have 2 Sunset Maples in my front yard. I am concerned because the Sunsets have flowered and now are covered with seeds, but the red maple in the backyard is bare – branches appear to have several inches of bright red growth and buds on the tips. I thought that all maples flowered, produced seed, and leafed out at approximately the same time. I don’t recall this tree being later than the others in past years. Could this just be the difference between Sunset cultivars and a basic red maple or could my tree have suddenly died?

Given that your red maple has signs of growth and buds, it is alive and well. It is just on a different time table than the other trees, which is completely normal. The leaf-out strategies of trees varies widely, both among and within species. The same tree can even leaf out/bud at different times each year. Some trees delay their leafing out during cold springs.
More information on this can be found in the following article (PDF):