I'm currently using wood and leaves from Quercus agrifolia in my substrate mix. The red color comes from very high concentrations of tannins in the wood.
I'm keeping Lucanus mazama and Lucanus elaphus in the mix and they're growing pretty well so far, but it's only about 20% Quercus agrifolia wood and leaves, the rest of the mix is very well-rotten acacia and fermented oak fuel pellets.
When people say evergreens shouldn't be used, they're referring to conifers. Most conifers are evergreens with the exception of a few types such as the dawn redwood. Hardwood trees that are evergreens can be used--evergreen is a designation used for plants that do not lose all of their leaves each year.