Above is a field sketch. Below is a small watercolor done
with this as an inspiration.
I don't necessarily use local color in my pastels and oils, but they are evident in my field studies--it is the fastest way for me to get the light right. Even my studio watercolor paintings like the one above is more representative of local color. (Yes, there is a lot of pink in the grasses.)
A note on fall greens. In the little study below I used some sap green which is a mixture of Quinacridone gold (PO49) and Pthalo green(PG7). I do use Quin gold but I'm a little leary of having powerful pthalo green on my palette. Even in the fall you need some green and the sap green is very useful. Last year I started to use Daniel Smith's Serpentine green. It is lovely and I seem to be going through a lot of it. It is expensive but I'm not sorry I bought a tube.