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White-tailed deer (Odocoileus virginianus) are economically important to rangeland operations in Texas and Oklahoma. Deer herd health, production and survival rates decline when population size exceeds the available forage. During winter, when rainfall is scarce and temperatures limit plant growth, white-tailed deer nutrition is limited and forage availability decreases drastically. During these times, white-tailed deer winter diets are mainly comprised of browse species because herbaceous production decreases as winter progresses. The objective of this study was to determine the influence of winter progression on nitrogen (N), neutral and acid detergent fiber (NDF and ADF) concentration and in vitro organic matter disappearance (IVOMD; free-range white-tailed deer rumen liquid) of six browse species of moderate to high forage importance in the Cross Timbers. Browse samples were collected during pre-frost, mid-winter, and late winter from four (replications) properties in north-central Texas over 2 years. Years did not affect (P>0.05) results. There was an interaction (P ? 0.05) between browse species and season for all forage values. Nitrogen, a desirable nutrient, decreased (P ? 0.05) as winter progressed while IVOMD also decreased (P ? 0.05) as fiber increased with winter progression in five of the six browse species. Texas oak (Quercus buckleyi) kept some of its leaves and nutritive value through early but not late winter. Live oak (Q. virginiana) kept its leaves throughout winter and maintained a mean 1.33% N with lowest (P ? 0.05) fiber levels and the highest (52.7%; P ? 0.05) IVOMD in late winter. Results confirm that nutritive value of browse, especially N and fiber, decreases in most but not all browse after the first freeze when most woody species shed leaves. It also emphasizes the need for plant biodiversity in habitat that supports adequate year-round white-tailed deer nutrition.