Maryland's Natural Areas

Scenic view of Allens Fresh Natural Area, photo by Kerry WixtedAllens Fresh, Charles County

Printable Version of Allens Fresh Natural Area

The expansive marshes of Allens Fresh lure paddlers upstream in pursuit of a bald eagle or osprey soaring overhead, a heron stalking the shoreline for prey, or perhaps the rise of a yellow perch or a glimpse of a northern river otter sliding down a marsh bank. Visitors witness the diminishing influence of tide and salinity as they proceed upstream. Brackish tidal marshes of cordgrass transition to fresh tidal marshes of wild rice, rice cutgrass and pickerelweed. The receding tide exposes sandy mudflats that provide habitat for the globally rare Long's bittercress (Cardamine longii, State listed as Endangered) and the rare wetland flower, spongy lophotocarpus (Sagittaria calycina). Beyond the marshes, tidal shrublands and forests of willow oak, green ash, and swamp rose yield to nontidal forests of cherrybark oak, red maple, blackgum and sweetgum.

The marshes and swamp forests of Allens Fresh help to maintain the water quality of the Potomac River and ultimately the Chesapeake Bay by absorbing nutrients and chemicals and trapping sediments that run off from roads, farm fields, and subdivisions. Even so, the sandy, tidal mudflats and rare plants are threatened by excessive runoff. Allens Fresh comprises more than 250 acres owned by the State and managed by the Maryland Park Service.

Photo Collage - Yellow Perch (USDA/Wikimedia Commons; Scarlet Tanager (Photo by Yukin Xing)


Rarity Refuge

Long's bittercress is a small plant of the mustard family named after Bayard Long, a Pennsylvania botanist who discovered it in the early 1900s. Its flowers have no petals, but produce tiny versions of the slender capsules that are typical of this plant family. Fewer than 100 populations of this plant are known to exist worldwide, and Allens Fresh harbors one of only two populations on Maryland's Western Shore.

Triumphant Return

Left: Bald Eagles nesting (Wikimedia Commons); Right: Osprey Hovering (NASA/Wikimedia Commons)

Bald eagles and ospreys are now abundant in Allens Fresh and along the shoreline of Charles County, but this wasn’t always the case. The widespread use of DDT and organochlorine pesticides in the mid-1900s led to a severe decline in the numbers of bald eagles and ospreys in the United States. These chemicals became concentrated through the food chain, absorbed by aquatic plants and fish, the birds' preferred food, and caused the birds to produce weak egg shells that broke in the nest or did not hatch. The bald eagle was federally listed as Endangered in 1967. 

With the ban on DDT in 1972, populations of eagles and ospreys began to recover. In 1995, the bald eagle was federally downlisted to Threatened, and in 2007 it was delisted. Maryland delisted the bald eagle from state regulation in 2010. Between 1997 and 2004, biologists documented a 10-fold population increase in bald eagles in Maryland. By the late 1990s over 3,500 pairs of osprey were thriving in the Chesapeake Bay watershed. Bald eagles and ospreys are now great examples of conservation success stories. As our nation’s symbol, the bald eagle continues to be protected under the U.S. Bald and Golden Eagle Protection Act, and both the bald eagle and the osprey are protected under the Migratory Bird Treaty Act.

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Map of Allens Fresh, Links to larger map 

MD DNR Map of Allens Fresh Natural Area

Special Note: Allens Fresh Natural Area is used seasonally by hunters.           



From Waldorf: Take US 301 (Crain Highway) south past Waldorf to La Plata. Continue south about 9 miles to MD 234 (Budds Creek Road). Turn left (east) and proceed about a mile to the canoe/kayak access areas on the north side of the road on either side of the Budds Creek Road bridge. Park in one of the access areas; keep alert to oncoming traffic.

Driving Directions links to Google Map
Aerial View - Links to Google Earth


Driving directions and aerial views open with Google Maps. For the aerial view button, if an aerial view does not open by default, click on the Satellite icon in the upper right corner and Google Maps will switch to an aerial view of the Natural Area.

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Scenic view of Allens Fresh Natural Area, photo by Kerry Wixted

Photo Collage:

The slow-moving, tidal waters at Allens Fresh, combined with ample vegetation, provide food and shelter for yellow perch. Photo by: USDA/Wikimedia Commons.

Left: Look for the handsome scarlet tanager within the forest interior. Despite their bold coloring, the birds are often undetected due to their secretive nature. Photo by: Yukun Xing.

The rare Long's bittercress grows only in tidal estuaries. Pollution, erosion and invasive species are its greatest threats. Photo by: Kerry Wixted

Photo Collage:

Left: Bald eagles prefer to build their massive stick nests in large trees along rivers and coastlines where they have easy access to aquatic prey. Some nests have been known to weigh as much as a ton. Photo by: Wikimedia Commons.

Right: Ospreys feed almost exclusively on fish and will plunge up to three feet underwater to capture their slippery prey. They will readily use man-made platforms to construct their bulky stick nests. Photo by: NASA/Wikimedia Commons.