When foraging optimally, mammalian herbivores should select food items that confer the greatest nutritional benefits (such as crude protein and non-structural carbohydrates) and impose minimal to no costs. Many plants defend themselves from herbivores by producing plant secondary metabolites (PSMs) that defend against herbivores. PSMs, such as tannins, deter herbivores by providing post-ingestive feedback cues that the forager experiences after a plant is consumed, and are therefore difficult for herbivores to avoid altogether. However, some PSMs such as terpenes are also volatile organic compounds (VOCs) that become gaseous at ambient temperatures and can be detected by herbivores via scent prior to ingestion. PSMs that can be detected prior to ingestion prevent herbivores from consuming a plant to begin with, and enable herbivores to avoid incurring costs while foraging. Our objective was to discern if the foraging preferences of white-tailed deer, a near ubiquitous herbivore in North America, were influenced by the nutritional (crude protein and non-structural carbohydrates) or anti-nutritional (tannin and polyphenol) constituents of trees during summer and winter. We also determined if the VOCs that were emitted by trees influenced the forage selection of deer by providing pre-ingestive cues. During summer, we found that deer preferred trees with a high non-structural carbohydrate content. During winter, deer preferred trees with a low crude protein content and a high tannin content. After sniffing trees that emitted a large proportion of monoterpenes and sesquiterpenes, deer were averse to begin foraging. In the few instances when deer foraged trees with high terpene contents, they consumed less than they did from low terpene trees. Our results suggest that VOCs, a long overlooked aspect of foraging ecology, may play a larger role in determining which plant species herbivores will avoid than the nutritional and anti-nutritional constituents of plants.