And I'm delighted with the results.
The dirt absorbed the glue and went darker than I'd hoped it would, so either a rethink or remedial action was called for.
So I thought perhaps sealing the fine dirt would help the absorption issue, so I airbrushed the area along with a freshly applied patch of dirt. I used Tamiya tan and light grey to lighten the base colour and try and get the ground closer to the tones seen in this image of Clovis.
I added a few scrubby plants,
Lots of tall yellow grasses.
Touch up the ballast edges and we're good to go.
Now it's time to build some turnouts!