The use and potential consequence of alien plant parts in the construction of open-cup leaf nests by Nearctic-breeding forest songbirds has not been investigated. We dissected 19 leaf nests constructed by Veeries (Catharus fuscescens) over two breeding seasons in a temperate broadleaf forest infested with alien plants. Our objectives were: (1) confirm the architectural approach used by Veeries to construct nests, (2) determine if Veeries used alien plant parts in nest construction, (3) determine if nest success was related to the use of alien material, (4) determine the use of alien plants relative to native plants, and (5) test for an association of alien plant mass with the progression of the nesting season. Our results showed that Veeries constructed three separate nest layers: (1) a platform for support, (2) an inner cup, and (3) nest lining. Veeries incorporated parts from six alien plant species in their nests representing 22% of the 27 species used. All nests contained alien plant parts but use differed among the three layers. In particular the use of stems of Alliaria petiolata and Rosa multiflora, two alien species, appeared to provide important structural support in the nest's outer layers. Although our sample size was small, we found no relationship between the use of alien plant parts and nest failure suggesting use of alien plant material does not have negative effects on productivity. We caution that sudden large-scale restoration efforts, which remove the alien forest plant species used in nest construction prior to the recovery of comparable native species, may result in the temporary reduction of materials available to birds for nest construction.