Three years ago, I purchased what I thought were two October Glory maples from a nearby nursery. (I live in zone 5 - Michigan) They were both about 20 feet tall and had large rootballs when I planted them. I planted them about 20 feet from each other, in the strip of grass between my sidewalk and street. They are planted in full sun, receive water a couple days a week when the sprinklers water the grass, and are extremely healthy and green during the summer.
In doing some closer identification last fall, I realized that one is an October Glory and the other is an Autumn Blaze. "Fine", I thought, because they should both turn red, which was my reason for purchasing October Glories. But I've been through THREE autumns with them now and neither of them turn red. They go from a healthy, full green foliage to yellow/brown and then the leaves fall off the tree by October 1.
The part I find so strange is that they are two different varieties of red maples, but neither ever turns red. If they were the same variety, I could maybe believe that they were both genetic duds that didn't have the capacity to turn red. But I don't buy that since they're two different varieties.
What could possibly be the problem? Is it an age issue? Gender issue (does being male vs. female have any effect on color?) Could it be a location issue (soil too warm between sidewalk and street?) Any insight and/or suggestions would be very appreciated.