The reason I asked about treating railroad ties is that I have an old retaining wall made of railroad ties. I recently signed a contract with a landscaper to extend the existing wall with new railroad ties. The landscaper assured me that new railroad ties would be used. It turns out that he now says he can't get new railroad ties. The ones he can get don't look as good as the ones on our 30+ year old wall. I'm looking for something that will enrich the color of the railroad ties he is using.