For those more inclined to shoo a spider outdoors than squash it, more apt to douse a candle than see a moth sputter to death in it, today’s Ants! trip near the C&O Canal may be just the way to spend a couple of summer hours. The two-mile round-trip walk, led by a park ranger, will visit the hills—often several feet high—of the Allegheny mound ants. Meet at 2 p.m. at the Great Falls Tavern Visitor Center, 11710 MacArthur Blvd., Potomac. $4 per vehicle. (301) 299-3613. (Andrew Webster)