Piñon—juniper (Pinus spp.—Juniperus spp.) woodlands are common throughout western North America, yet relatively little is known about the habitat use and requirements for many members of its avian community. During summer 2005–2007, we assessed avian nesting substrates within piñon (Pinus edulis)— juniper (Juniperus osteosperma) woodlands in northwestern New Mexico. Of all nests in live trees, 86% were in junipers. The selection of juniper as a nest tree was significantly higher than expected from the region's piñon—juniper ratio (1:1.06) for the community as a whole, for both open cup and cavity nesting species, and for 8 species (of which 6 are piñon—juniper obligate or semiñobligate species). Nest survival, however, was not higher in juniper than in piñon for the nesting community as a whole or for chipping sparrows (Spizella passerina), the single species that was well represented nesting in piñon. The high use of juniper as a nesting substrate differs from previous studies, which have suggested that a presence of piñon is among the most important habitat features for many piñon—juniper species. Because of their importance to nesting birds, managers should avoid preferential thinning of junipers within piñon—juniper woodlands.