At a Glance

Hours: Sunrise to sunset.

Cost: Free.

Tips: No restrooms. Nearest restrooms are at Mount Zion Park, about a mile away at 5130 Brookeville Road. ■ A scope is recommended. ■ Waterproof boots are recommended when it has been raining.

Best Seasons: Spring and fall.

Breeding Bird Atlas Block: Sandy Spring CW

Local MOS Chapter: Montgomery Bird Club

Blue Mash Nature Trail

Nature Trail Parking – 20600 Zion Road, Laytonsville, MD 20833
Mixed-use Trail Parking – 6001 Olney-Laytonsville Road, Laytonsville, MD 20882
(301) 495-4500

The Blue Mash Nature Trail, near Laytonsville in Montgomery County, lies in the buffer area of the  former Oaks Landfill, which closed in 1997. After the landfill closed, the Montgomery County Department of Environmental Protection worked with other agencies and with  members of the local community to plan the public nature trail. The Nature Trail and an adjoining mixed-use trail (for  hikers, bikers, and horseback riders) opened  in 2001. The area open for public use occupies about 245 acres of county-owned land. The natural-surfaced Nature Trail, 1.6 miles long, has proven consistently birdy, with a nice mixture of habitats and a corresponding variety of birds. Additional habitat can be viewed from the 2.75-mile mixed-use trail. The trails follow an arc around the old landfill, which is in a restricted, fenced area not open to the public.

Because of the  diverse habitat, including two ponds, fields, thickets, and both young and mature woods, many different families of birds can be seen, including songbirds, flycatchers, waterfowl, shorebirds, herons, and raptors. Birders usually cover the Nature Trail, a level, circuit-route trail that conveniently begins and ends at a parking lot off Zion Road. To obtain a good view of a large pond and other areas within the restricted landfill area, from the parking lot, walk down the broad dirt road toward the main gate of the landfill.  Shortly before you get to the gate that blocks landfill access, look for a narrow path going to the left.  The path leads to an open area just behind a long chain-link fence through which the pond and other areas can be scoped.

The mixed-use trail starts on the opposite side of the old landfill, on its western edge, and is served by a separate parking area for equestrians, bikers, and other users; this second parking area is located off Route 108/Olney-Laytonsville Road (see trail map at link at left).

The trails at Blue Mash are maintained by the Montgomery County Department of Environmental Protection with assistance from local volunteers.


Over 230 species of birds have been reported on eBird for the Blue Mash Nature Trail (225+ species) and at the separate eBird hotspot for the former Oaks Landfill (164+ species).

Northern Harriers and occasionally Short-eared Owls have been seen hunting over the former landfill from the Blue Mash Nature Trail. In dry years (such as 2007), the landfill pond is attractive to shorebirds, and when well-watered, both ponds host several species of ducks and waders. Grasses on the pond edges have sheltered nesting Wood Ducks and Green Herons. A wet grassy swale through the center of the area has produced American Bittern and frequently, Swamp Sparrow. There are many junipers (Eastern Red Cedar) dotted throughout the Nature Trail area, and a Long-eared Owl was once flushed from one of these.  Many bird houses attract Eastern Bluebird and (particularly) Tree Swallows.

Regularly seen are Green-winged Teal; Bufflehead; Hooded Merganser; Red-shouldered, Red-tailed, and Cooper’s Hawks; Northern Harrier; Barred Owl; both vultures; Greater and Lesser Yellowlegs; Solitary Sandpiper; Spotted Sandpiper; Killdeer; Great Blue Heron; Green Heron; Pileated Woodpecker; and Northern Flicker.

In spring and early summer, White-eyed Vireo, Yellow-billed Cuckoo, Indigo Bunting and both orioles are usually resident, along with more common birds like the three mimids, Eastern Bluebirds, chickadees, titmice, and other small woodland species. Nesting species include Wood Duck; Great Horned Owl; Willow Flycatcher; Yellow-breasted Chat; Ovenbird; Yellow Warbler; Orchard Oriole; Baltimore Oriole; Scarlet Tanager; Indigo Bunting; and  Blue Grosbeak

In migration one might see many eastern warblers and vireos, Broad-winged Hawk, American Bittern, and Wilson’s Snipe. In fall or winter, a good variety of sparrows is possible, including Fox (regular in March and November), White-crowned, White-throated, American Tree, Savannah, and Lincoln’s, in addition to resident Song, Field, and Chipping Sparrows.

In the wooded northern part of the park, Scarlet Tanager, Wood Thrush, and Great Horned Owl usually nest, and Barred Owl is common in the woods on the south side of the Nature Trail area.

Wheelchair Access: 

The trails at Blue Mash are natural surface and are fairly flat and level, but would not be suitable for most wheelchairs because of soft and/or wet conditions.

Pet Policy:

Pets are allowed on leash; pick up after your pet.

Special Features:

Montgomery Parks has an interactive map available at As you zoom in on a county park, detailed features such as trails, parking, picnic areas, trailheads, and restrooms will be displayed.

Local MOS Chapter:

The local chapter of the Maryland Ornithological Society is the Montgomery Bird Club, which offers field trips and meetings with informative programs, all free and open to the public.

The Montgomery Bird Club has published A Birder’s Guide to Montgomery County, Maryland (2008); this comprehensive, detailed book covers 17 major birding sites plus 18 “little treasures” in the county. The book is now out of print but is available as a free downloadable PDF, courtesy of the Montgomery Bird Club.


Unpaved lots off of Zion Road (preferred for Nature Trail) and Route 108 (for mixed-use trail). The Zion Road parking lot will hold about 12 cars, and a few more can park on the gravel entry road.


From I-495/DC Beltway: Take Exit 31 for MD Route 97/Georgia Avenue Northbound. Follow MD Route 97 north for about 10 miles, to the town of Olney. Turn left to go northwest on MD Route 108/Olney Laytonsville Road. After 2.5 miles, turn right to go north on MD Route 582/Zion Road*. The entrance to the parking area for the Blue Mash Nature Trail will be ahead on the left (west) side of the road in about 1.1 miles.

*If you prefer to use the parking area for the mixed-use trail, instead of turning north on Zion Road, stay on Route 108 and go another 1.4 miles. The entrance to the parking area for the Mixed-Use Trail will be on the right (north) side of the road, at Fieldcrest Road. Turn right onto Fieldcrest and then left into the parking area.

Nearby Sites:

Montgomery County: Black Hill Regional Park ■  C&O Canal – Pennyfield, Violette’s & Riley’s Locks ■ Little Bennett Regional Park ■ Lois Y. Green Conservation Park ■ McKee-Beshers Wildlife Management Area (Hughes Hollow)Rock Creek Regional Park – Lake Needwood ■ Rock Creek Regional Park – Meadowside Nature Center & Lake Frank ■ Seneca Creek State Park ■ Triadelphia Reservoir (Brighton Dam)Wheaton Regional Park – Brookside Gardens, Brookside Nature Center, Pine Lake Area


HedgerowsUpland Deciduous Reclaimed Industrial SiteSuburban Neighborhood Hay Meadows, Pasture, Grass FieldOld Fields, Shrubby Meadows Freshwater Pond, Lake, or Reservoir


BeginnersBicycle Trails (Bikes may be prohibited on some trails)Free - No Entry Fee at Any TimeHabitat Restoration ProjectHiking/Walking TrailsNative Plant Garden or Meadow/Pollinator PlantsParkingPets AllowedWater ViewYoung People / Families


County Parks