Boards of eastern white pine, eastern white spruce, and red pine were impregnated with an ammoniacal zinc salt-latex system and exposed outdoors along with untreated western red cedar boards. Their performance was evaluated at different stages of weathering for general appearance and for discolorations arising from fungal, extractive, and iron nail stains. The performance of the treated boards improved. Outdoor performance of less durable species such as pines can be upgraded to be comparable with that of cedars. -- AATA