Most of Crowders Mountain is a mature climax forest of hardwoods Chestnut Oak forest. Areas once disturbed by fire and logging are now being restored by the processes of succession. Shrubby growth, followed by pines, is now being replaced by hardwoods such as red maple, American beech and several varieties of oak.
Beautiful blossoms may be encountered along park trails. Flowering dogwood is plentiful and spring-blooming mountain laurel is abundant throughout the park, particularly on Crowders and Pinnacle trails. Rhododendron also grows at high elevations.
Ferns, from the delicate to the hardy, are common in the park. Ferns that are more than six feet tall grow on the north ridge of Crowders Mountain. Bracken fern grows in sunny spots and cinnamon, netted chain and southern lady ferns grow along the streams and in the moist soil of bogs.
The ridge-top Piedmont Monadnock forest is unusual as many species, especially Virginia pine, are dwarfs growing only 3 to 6 feet in height. A few specimens of the blighted American chestnut still persist on the ridge. The park's forests are home to an abundant and diverse animal population, though many species are evidenced only by an occasional footprint. Crayfish, minnows and a variety of frogs make their homes in clear, cold streams. Creek mud and boggy soil often show signs of muskrat, raccoon and Virginia opossum. Dusky and two-lined salamanders are often found under rotted logs, leaves and rocks in moist areas. Wetland habitats also house many species of turtles, such as mud, snapping and spiny softshell turtles.
Upland areas and mountain ridges support a variety of animals including chipmunk, eastern cottontail, and red and gray foxes. The tunnels of eastern moles, formed when the small burrowers search for food below ground, are often seen in the soft earth along hiking trails. Among resident amphibians and reptiles are Fowler's and American toads, slimy salamanders, eastern box turtles and several species of snakes. Though most of the snakes found in the park are harmless and rarely encountered, the copperhead and timber rattlesnake are venomous and hikers should be alert.
Birds are abundant in all seasons, especially in spring when migrating aviates add to the resident population and the otherwise quiet mountain air is filled with the melodies of songbirds. More than 160 species of birds, including waterfowl, wading birds, hawks, owls and woodpeckers have been recorded in the park. While some birds visit the park only for a season, others make the park their permanent home. Among them are black and turkey vultures that roost on isolated rock outcrops near the mountain peaks and fly into the surrounding countryside in search of food.