On a day declared Code Red by the National Weather Service, a rusty brown wood thrush sang its song in the cool cover of trees in the Sweathouse Branch of Gunpowder Falls State Park, unaware that it was unhealthful to be outside.
"I think it has the most melodious song in the woods," said Ranger Mike Browning, of the state Department of Natural Resources. "This is a great bird-watching area."
The sound of traffic from busy Belair Road, which borders the Sweathouse Branch area of the park, was barely audible 100 yards from the highway.
The 800-acre Sweathouse Branch, a couple of miles northwest of bustling Perry Hall in Baltimore County and about five miles outside the beltway, has been declared a wildland area by the state, which means no change from its natural state will be permitted.
That means construction, timbering, mechanical conveyances such as bicycles, not even visitors' centers or trash barrels will be allowed to mar the natural beauty of the wildland, which will be reserved for hiking, nature study and fishing.
The Sweathouse Branch, named after a stream that traverses the wildland and feeds into Gunpowder Falls, is part of about 26,000 acres of Maryland parkland in nine counties elected to become wildland. The change is subject to the approval of the legislature and the governor during the next General Assembly session. About 14,000 acres of state parkland already have such a designation.
The area is part of the 13,000-acre Gunpowder Falls State Park in Baltimore and Harford counties.
"The park overall was created to protect the Gunpowder valley from development and to give citizens access to natural wonders," said the DNR's Bob Graham.
"I think the fact that brown and rainbow trout -- which are very sensitive to the environment -- survive in the Gunpowder prove the river's vitality and the success of preservation efforts," he said.
Small-mouth bass, catfish, eels and carp also abound in Gunpowder Falls, which is open to fishing.
Peyton Taylor, a ranger who lives in the park, noted the existence of wildflowers in abundance, including Virginia Bluebells, mullein, hepatica and anemones, plus 14 kinds of ferns.
"It's especially beautiful in the spring," she said.
Virginia pines dominate the ridge lines in the park, with chestnut oak, scarlet oak, black oak and hickory taking over on the descent into the valley. Tulip poplar, beech, white and red oak, red and sugar maple, and black walnut thrive in the lower parts.
Sycamores, sweet gum, box elder, willow and alder grow along the river bank.
"This is an excellent example of a mature forest, and it's going to be left untouched," Mr. Graham said. "There will be no timbering, and the trees will lay where they fall, unless they're blocking a path or presenting a danger to hikers."
Earl Copenhaver, ranger in charge of the central area of the park, of which the Sweathouse Branch is a part, said numerous park-sponsored activities are available to visitors, including nature walks, bird-watching tours and programs for children.
"The wildland designation means it is to be left in its natural state, but we still have to make it available to the public," he said.
The Gunpowder Falls is about 50 yards wide where it passes under Belair Road at the park, but grows to a mile and half after it merges with the Little Gunpowder Falls at Days Cove in eastern Baltimore County, just before it empties into the Chesapeake Bay.
A parking lot and entrance to the Sweathouse Branch wildland is on the east side of Belair Road, about 5.5 miles outside the beltway.