Furniture, Wood and Cabinetry Finishing - Knotty pine walls with light marks.

Recently purchased a log home with all knotty pine walls. Not sure if previous owners were smokers, or light patches are due to them using the fireplace (smoke), but............

I have light patches (square) wherever framed pictures were removed (their pictures, not ours).

I need some ideas on darkening up these areas to match the rest of the walls.

I'm thinking this would be easier then lighting all the walls to match the squares (there are a lot more walls than lightened squares).

Any ideas would be appreciated.

Pine yellows and darkens with exposure to light. The squares are probably where pictures and such were mounted. Exposing the light portions to light will enable them to darken after a while. In order to make the darkness or color uniform in the short run would involve stripping and refinishing the wood in its entireity.

Hope this helps.