Uneven absorption can cause stained wood furniture or trim to look blotchy. To correct varied tone on hardwoods, such as maple or oak, restain lighter areas while still damp. Rub out dark spots with a rag dipped in mineral spirits. The trick with a soft-wood like pine, which has an open cell structure that can soak up too much stain, is to brush on a clear conditioner first, to partially block some of the wood pores. Once applied, you can often stain within 15 minutes.