After finishing up just before the gates closed at 5:30 at Lilypons, I headed down the road to the bridge over the Monocacy River on Rt 28 and the trailhead for a number of paths through the Monocacy Natural Resources Management Area near Dickerson.
It was already getting pretty dim on the trail, which is mostly heavily shaded, by the time I got on the trail at 6 pm. But I quickly spotted first one, then a dogfight of three or four, Northern pearly-eyes — quite fresh, very dark, and with impressively large eyespots. All the pearly-eyes I saw (8 total) were in the first quarter mile or so of the trail.
In most places, the trail is single-file and crowded on both sides with the introduced invasive Japanese stiltgrass, Microstegium vimineum. Two females farthest down the trail were both fluttering mothlike in the gathering twilight in the stiltgrass, and I watched both oviposit multiple times on the wide blades. Most of the eggs were in clusters; the one I examined most closely was a cluster of four, greenish eggs laid singly but touching each other on the underside of the leaf.
Similar behavior has been noticed before along the Potomac by Robert Robbins.
There are a number of glades and clearings father down the trail that deserve a good look in the middle of the day when it’s sunny along the trail; I expect to head back soon.