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I planted the Bur in March and have been excited to see it leaf out. I have noticed that a good number of the leaves aren't the typical dark green that I've seen, and am attributing this to stress. That being said, the leaves are a mixture of light green to yellow/bronze. The veins themselves are still green and the leaves don't appear to be wilting so far. I've also read that this could be a sign of over or under watering the tree. I've attached a photo to better highlight what I am seeing. Any help you could offer to get this tree in good shape would be appreciated.

Answer from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/19/17) -

The leaves look perfect for this time of year. Many plant leaves have some red in them as they emerge, but before they mature. The chlorophyll that will absorb sunlight and use that energy (along with CO2 and water) to make food through photosynthesis is not fully mature at first, and the sun would bleach the chlorophyll without some protection. The red pigment is there to absorb that light and protect the chlorophyll until it can absorb light on its own and use the energy. Some trees retain the red pigment and are more-or-less red all summer, while with others it fades and the leaves end up pure green. Your bur oak will be the latter. In a cool, prolonged spring like we are having this year, the red may hang around longer since the development of the chlorophyll is delayed.