The legislative authorization of some United States national historical parks (NHP) includes maintaining an agricultural landscape as a management objective. This management objective can prove difficult to accomplish in some NHP given increasing white-tailed deer (Odocoileus virginianus) densities. Our goal was to quantify the impact of white-tailed deer foraging on agricultural landscapes in forested NHPs in Maryland, USA. We monitored 12 and 13 corn (Zea mays) fields at 3 NHP during the 2003 and 2004, respectively. Each field had 3 5 × 5-m fenced and unfenced plots along the edge and a similar set within the interior of the field. Within each plot we examined the number of stalks with corn, corn ear quality, and field weight prior to harvest. Fenced plots had higher weights of corn, more stalks with corn ears, and higher quality corn than unfenced plots. Estimates of silage yield based on crop weights indicate deer reduced silage yield in individual fields by 5–43% during the study period. Crop loss differed between years and fields, with plots in the Chesapeake and Ohio Canal NHP sustaining the highest crop weight loss (28%). Eventual crop loss was correlated with proportion of corn plants browsed within 2 weeks of emergence. Some variability in loss between fields was due to landscape metrics, as fields surrounded by more forest experienced the highest loss. Our results indicate the NHP agriculture fields we studied receive significant deer damage to corn crops and may not be able to maintain mandated management without regulating deer numbers.