Gettysburg National Military Park

Gettysburg National Military Park


Prairies and Grasslands

Grasslands are considered by many as one of the most endangered ecosystems globally. Grasslands were once abundant in the 1800’s when settlers had cleared much land for hayfields and pastures.  Today grasslands face danger from fires, human development, and changes in agriculture technology.

Grasslands are important because they protect large amounts of open space and provide wildlife and nesting habitat for specialized species.  The ecosystem is especially important to birds such as the Bobolink, Savannah sparrow, and the Eastern meadowlark. Grassland birds require large contiguous patches of grassland habitat for successful breeding. Many grassland birds will only nest in this type of open grassland habitat and decline in grasslands causes decline in breeding birds.

Much of Gettysburg NMP is considered grassland habitat. The park was designated one of several Important Bird Areas in Pennsylvania set aside to protect birds and grassland habitat. In efforts to maintain the characteristics of an 1863 landscape much of the main battle action resource areas are being converted from large agricultural fields to smaller contiguous patches of native grasses. The restored field patterns will better reflect historic 1863 conditions and provide valuable grassland habitat.

Nonnative Species

Most non-native species of the park are in the form of plants in which 143 of the 553 plant species are non-native. Non-native invasive plant species can be threats to natural ecosystems and native flora of the park. These species often grow quickly and crowd out native plant species while providing limited habitat worth to park wildlife.

The Gettysburg NMP Natural Resources staff works to control non-native invasive vegetation to restore native vegetative communities.    Plants species that provide the biggest challenge to park staff are multiflora rose, Japanese barberry, Ailanthus, and Mile-a-minute weed. With the help from the Mid-Atlantic Plant Management Team, based out of Shenandoah National Park, efforts are combined to treat these exotic species by chemical methods, mechanical methods, and hand pulling.

There are also several non-native insects in the park that put stresses on the park’s native vegetation. An insect of concern is the Hemlock wooly adelgids, Adelges tsugae, a pest species that negatively impacts the growth of the Eastern Hemlock. “Hemlock wooly adelgids (HWA) is the single greatest threat to Hemlock health and sustainability…” USDA. HWA is believed to be an introduced species from Asia, first documented in the States around 1924. Currently there are no effective natural enemies known to keep the pests in balance. However, park staff annually monitors infestations on both the battleground and the Soldiers’ National Cemetery. When HWA populations are high approved chemical methods are used to protect the trees.


Springtime in the park brings from the ground ephemeral wildflowers that cover the landscape with a mosaic of colors like paint on a canvas. Many of these flowers cover stream banks and woodland areas before the trees spread their leaves and block the sunlight. Virginia bluebells and violets are a few of the many wildflowers to bloom in the spring.

From summer to fall, the field and forest floors will come to life with the many species of aster and goldenrod found in the park. Their relative, the black-eyed susan is one of the most common wildflowers in America and is abundant throughout the park. Visitors can also be treated by the sight of the cardinal flower, a favorite to hummingbirds and distinguishable by its bright scarlet flower.


The variety of habitats within the park ranging from forests to wetlands provides home to 553 species of vascular plants, 410 of which are native. The Pennsylvania Natural Diversity Inventory has also listed 23 of these plants as endangered, threatened, or species of special concern.

In the forested areas of the park, the dominant overstory species documented in woodlots and woodlands are white oak, white ash, and northern red oak. A mixture of black cherry, spicebush and white ash saplings dominates the understory. Beside woody plant species there are an abundant variety of herbaceous plants and wildflowers that occupy both forested and open areas.

Open fields and field edges boast a diverse mixture of vegetation for both the visitor to observe and for wildlife to utilize as either cover or feed. Currently the park is transitioning portions of agricultural lands into warm season grasses to encourage a more diverse plant community for open-upland bird species.

Vegetation management is an important responsibility of the park's natural resource staff. The primary goals of Natural Resource Planning at Gettysburg and Eisenhower are to (1) restore and perpetuate the battlefield as it appeared at the time of the Battle of Gettysburg in July 1863 and to (2) preserve resident fauna and flora that are compatible with the goal of historic accuracy. With these goals, park personnel conduct floral inventories, monitor seedling recruitment, and map vegetative cover types. Vegetation management is also a critical part of the park's landscape rehabilitation plan.

National Park Service staff also work to combat several invasive plant species such as the multifloral rose, Japanese barberry, ailanthus, and mile-a-minute. Six weeks each year, staff with the help of the Mid-Atlantic Plant Management Team treats these exotic species by chemical methods, mechanical methods, hand pulling and sprays.

Trees and Shrubs

Settlers cleared most of the original forest of the Gettysburg area for farming in the 18th and 19th centuries. Today wooded areas are in patches scattered across agricultural land. Penn State University surveyed six woodlots for species composition and community structure.Typical tree species of the forest include oaks, hickory, and poplar, which are common to the Appalachian area. The predominant overstory species of the wooded areas are white oak, white ash, and northern red oak. Common seedlings and saplings include spicebush, black cherry, and white ash. Also the state endangered shrub, the Missouri gooseberry, occurs through the northern section of the park.