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Control of woody invasive species, primarily eastern redcedar (Juniperus virginiana), is a priority land use issue among landowners and managers. While maintaining open habitat for obligate grassland bird species, there is a need to understand how brush management affects birds adapted to early-succession habitats, some of which are declining at statistically significant rates. To assess bird-habitat associations in the context of brush management, study sites were stratified by percent canopy cover of eastern redcedar, (0% canopy cover [open grassland], < 5% canopy cover [encroachment level], and > 5% canopy cover [infestation level]). We used repeated point count sampling to quantify abundance and species composition of breeding bird communities. Data were collected in mixed grass and sand prairie habitats of Barton County Kansas from 2011-2012. Our results indicate that bird diversity within ecological function groups (nest placement and habitat preference) vary across the gradient of eastern redcedar encroachment. A cluster analysis defined three groups of species on the basis of their association with the encroachment gradient. Canonical correspondence analysis revealed that grassland bird species distributions were strongly correlated with percent tree canopy cover and visual obstruction. Sites with redcedar infestation were preferred by lark sparrows (Chondestes grammacus) and Bell's vireos (Vireo bellii), which suggests that the current brush management recommendations might diminish quality habitat availability for these species of concern. Considering the diverse habitat requirements of grassland birds, landowners and managers should assess how conservation practices for one species might affect others.