New Jersey Butterfly Sites

Flatbrookville (Delaware Water Gap NRA)

by Tom Halliwell

County: Sussex.

Municipality: Walpack Township.

Directions: Take Route 80 to Exit 12 (Hope-Blairstown). At end of ramp take Route 521 N for several miles to Blairstown. Turn left onto Route 94 S. Go a very short distance to the traffic light and turn right. Be careful here: Take the 90-degree right; DO NOT FOLLOW ROUTE 521 WHICH MAKES A BACKSLANTING RIGHT. Go past the church, up the hill, and turn right at the top onto Route 602 (Millbrook Road). In a short distance bear left (which is still Route 602-Millbrook Road). Follow this for a number of miles, up and over the Kittatinny Ridge. When you have descended the back side of the Ridge you will come to Millbrook Village, a restored late-19th-century village. In Millbrook Village turn right (north) on Millbrook-Flatbrookville Road, which is a portion of Old Mine Road. Travel for 2–3 miles up and down the mountain until you come to a T just after crossing the Flat Brook. Turn left and in about a mile park in the large pulloff on the left just where Old Mine Road makes a 180-degree bend to the right. Be sure not to block the gate.

From the north take Route 206 to the right turn onto Struble Road (DeLorme 18: J-12). This is a few tenths of a mile north of the turnoff to Stokes Forest HQ or about a mile south of the turnoff leading to Layton (Route 560). Take this road for 5–6 miles to the T with CR 615 in Walpack Village. Along the way you will have passed Tillman Ravine, Walpack Cemetery, and crossed the iron bridge over the Flat Brook. Turn left onto CR 615 (aka Walpack-Flatbrookville Road) at the T and stay on it for 8–9 miles until you reach the 180-degree turn mentioned above. Park on the left. Be sure not to block the gate.

Parking: Yes. See the pulloff under “directions” above. You will find additional pulloffs with butterfly fields on Walpack-Flatbrookville Road along the Big Flat Brook. Exploring the area’s roads will no doubt yield additional stops with excellent butterflying.

Nearest sizable town: None. Blairstown and Layton are 10+ miles away. Gas up and bring supplies before leaving.

Habitats: In addition to three large old-fields—the largest with much Little Bluestem grass—Flatbrookville includes extensive areas of deciduous forest, Eastern Redcedar woods and openings, and a large White Pine forest. The Flat Brook is bordered by a wooded riparian corridor, and the Delaware River has a large, mostly forested floodplain.

Maintained/Marked trails: Limited. Butterflying here is done mainly along paved roads or old farm roads or, more typically, in the adjacent fields.

Restrooms: None. Restrooms are available in Millbrook Village if coming via Route 80. If coming from the north a portable toilet is available at the church in Walpack Village, and the 2 parking lots along Tillman’s Ravine have pit toilets.

Picnic tables: No. The Group Camping Area just uphill (south) from the bridge over the Flat Brook is a very scenic area overlooking the Walpack Bend of the Delaware River. It has excellent picnic facilities and pit toilets, but a permit is required. If the gate is open on a weekday in spring or fall (when no campers are likely to be present) you might try driving in to eat lunch at a picnic table.

Notable species: Falcate Orangetip, American Copper, Eastern Pine Elfin, Juniper Hairstreak, Aphrodite Fritillary, Hackberry and Tawny Emperors, Northern Pearly-eye, Common Ringlet, Appalachian Brown, Southern Cloudywing, and Leonard’s, Cobweb, Indian, Crossline, and Dusted Skippers.

Best time to visit: Any time from May to September.

Exploring Flatbrookville: From the parking area at the 180-degree bend on Old Mine Road walk past the gate on the left and down the hill along an old farm road. Between the gate and the boarded-up farmhouse look for Hackberry and Tawny emperors. You certainly will find a few very large Hackberry trees. Sometimes the openings around the farmhouse can have a good growth of Common Milkweed and/or other nectar plants. Banded, Hickory, and Gray hairstreaks have been seen here as well as Pipevine Swallowtail. Just before following the farm road into the large White Pines be sure to check for Appalachian Brown on the roadside. After entering the pines be alert for Northern Pearly-eye, which is regular here. A hundred yards or so into the pines begin “bushwhacking” off to the right of the road, where you will enter an Eastern Redcedar woodland. As you wander around in here (be careful not to get lost!) you will find many small openings where a late-flying population of Falcate Orangetips occurs in late May. Their emergence here seems synchronized with the budding of Tower Mustard, which flowers later than the plants used by the orangetips elsewhere (especially Smooth and Lyre-leaved Rock Cress).

Returning to the farm road, you will emerge from the pines into an enormous field dominated by Little Bluestem grass. Spend considerable time here. In spring look for Eastern Pine Elfin nectaring on Cypress Spurge, American Copper (sometimes triple-digit counts), Juniper Hairstreak, and Common Ringlet. Cobweb, Indian, and Dusted skippers have been found, but are rare. Both Northern and Southern Cloudywing (and seeming intermediates) also occur here, the Southern usually late May into June. In summer check the mountainmints, milkweeds, and, later, the thistles for American Copper, Juniper Hairstreak, American Snout, Common Ringlet, and Leonard’s and Crossline skippers (Crossline is fairly common; Leonard’s quite uncommon). Summer rarities that have occurred here over the years include Bronze Copper, White M Hairstreak, Aphrodite Fritillary (more than once), and Milbert’s Tortoiseshell.

Although not likely to produce additional butterfly species, continuing on the farm road all the way to the Delaware River is a wonderful walk through a largely White Pine forest. It will take about 20-30 minutes and ends at a lovely floodplain area unreachable except by foot or canoe.

Returning to your car, you might like to make another quick stop. Drive back the way you came. Don’t turn over the Flat Brook bridge, but go straight for a bit less than a mile and park on the left opposite the concrete stream gauging station (known familiarly as the “phone booth”). Check out the puddles next to the road (when present) for anglewings, Juvenal’s Duskywing, swallowtails, emperors, and skippers. Compton Tortoiseshell has been seen here more than once. The field upslope from the parking area formerly held a nice population of Meadow Fritillary but it seems to be losing out to an invasive Shrubby St. Johnswort. Baltimore Checkerspot has also been found here on a few occasions. Walk along the right side of the road back toward the Flat Brook bridge, checking for Meadow Fritillary flying among the grasses. Soon you will come to a large field on the right opposite a non-functioning bridge over the stream. This field is worth checking out especially when Common Milkweed and Wild Bergamot are in flower. Aphrodite has been found here several times.

Any non-agricultural field (with nectar flowers) or unpaved road in the park is worth exploring for butterflies.

Special precautions: Ticks can be quite common in the fields. In addition to repellent, rubber knee boots are helpful in keeping them off. Bears may be present anywhere, but they are generally happy to avoid you.

You might also want to visit: Walpack area, Blue Mountain Lakes Road, Crater Lake Road, and the Appalachian Trail where it crosses Millbrook Gap.

General information about this National Recreation Area can be found at

To view a larger map, click on 'View larger map' icon in upper right hand corner. (Tip: The satellite view may also suggest good potential butterfly habitat to explore.)

Flatbrookville mIg field

North Jersey Butterfly Club members exploring the main field at Flatbrookville.

River Bend farmhouse

Woods road near farmhouse.

White Lake NRA Barn

Eastern Redcedar glades.

Trail to river through pines

Trail to river through pines.

Delaware River floodplain

Delaware River floodplain.

Stream gauging station (

Stream gauging station ("phone booth") and puddle.