SPARKS, Md. – Offering his lunch guests a touch of cool watermelon on a warm Saturday afternoon, Steven Knapp instructs his eating companions to be careful what they throw away.

Watermelon rinds? Save them. It’s sheep feed.

Plastic plates? Give them a scrubbing and keep them handy for later use.

On the new University president’s farm in suburban Maryland, those enjoying Knapp’s hospitality don’t leave without a crash course in conservation. Everything from food discards to flatware to even his livestock’s excrement (used as fertilizer for the vegetable garden) serves an environmentally friendly purpose on his 6 1/2-acre property.

“So far as you can, everyone needs to be intentionally responsible and think about the impact they have on the environment,” said Knapp, a 56-year-old who just as easily can put on a suit and loafers as he can a tan Canadian hiking hat and waterproof sandals.

Born in North Jersey, educated at two Ivys and an Oakland, Calif. resident for 16 years, Knapp might not seem the agrarian type. But after taking a post at Johns Hopkins University in late 1994, the once-city dweller went “green” – well before it became a popular movement.

With about 85 percent of his property undeveloped, Knapp could have sold part of his back lot to be built upon, but then-dean of Hopkins’ liberal arts school said he would have none of that.

“Preserving green space is important,” he said. Wanting the space to remain a pasture, he rebuffed deals to slice off his grassy backyard.

But that wasn’t enough.

Why have a pasture if it’s vegetation served no purpose? Livestock could live off the land, Knapp figured, and it would be a welcome addition to property that was originally a tenant farm in the 19th century. (Not to mention, “It took eight hours to trim the grass, so we needed something to eat it.”)

Horses are too expensive, a bit too difficult to maintain. Goats are too hard to catch. So the Knapp family – Steven, his wife Diane, and children Jesse and Sarah – decided on sheep.

When a visitor tried to photograph one member of the flock, Diane recommended against taking pictures. Her husband exclaimed, half-jokingly, “We don’t want to embarrass her.” Snowy, as the Knapps named her, is the oldest sheep at 14, and she has dark lesions that contrast with her just off-white complexion.

These days, the largest group of animals on the farm is the chickens. How many fowl are in their coop is up for debate. When asked, Knapp did not even attempt to guess.

“It’s hard to count because they don’t hold still when you’re trying to count,” he said. An approximate count by this reporter yielded 32, but in addition to moving about the netted area very quickly, many look alike.

A few are quite distinguishable, though. A breed called the Polish Top Hat stood out, as these hens’ heads were adorned with a puffy layer of feathers. Knapp explained the derivation of their name came from Polish cattle ranchers who sported head coverings similar to the birds.

The chicken coop is situated next to the sheep’s wooden barn, which was constructed in the mid-1800s. The farmhouse, in comparison, is much more modern. It was built around the turn-of-the-century, placed atop a stone foundation, Knapp said. All of the property is situated on what used to be an agrarian manor, halfway between Baltimore and the state line with Pennsylvania.

The guesthouse, which is comprised of a small kitchen, a living room, two bathrooms and a loft teeming with Knapp’s books and musical instruments, used to be a horse clinic. Hundreds of books – some neatly stacked on shelves, others in piles waiting to be packed for the move to Washington – consume the second floor.

Called a “caj?n” in Spanish, a box drum is a percussion instrument the musician sits and rhythmically bangs, taps and strokes the wood. Knapp sat atop one such Afro-Peruvian drum – his legs clothed in linen pants, wrapped around the two wider sides of the tan-colored box – and began playing.

A loud strike to the middle with his right hand.

A quick slap with his left, his Citizen watch trying to weather the compression.

This cultural pastime, much like the aspects of his rustic lifestyle on the farm, has now become much harder to come by as GW’s president moved back to urban life.

Planning to move into Alumni House, on 20th and F streets, after renovations are complete in more than a year, Knapp is temporarily living in an apartment at 2400 M Street. He fears the thunderous concussions of caj?n drums might upset the neighbors.

“It’s a sad thing to think about . I’m just realizing that in an apartment building, that may be a little bit of an issue unless I can put a lot of egg cartons to help block the sound,” Knapp said relaxing in June in his screened-in patio in Sparks, which is about 65 miles northeast of the District.

The luxury apartment building allows only domesticated animals under 45 pounds. That keeps out the sheep, chickens and Peppy, the family’s Australian shepherd, who begs to play “fetch” with any loose stick from the pasture or off the Knapps’ badminton court.

One of Steven and Diane’s cats will accompany them to their rental unit. Sarah will stay back at the farm and help tend to the animals, which she has helped care for since she was nine.

A full month into his new job, Knapp said this week that he would like to take weekend trips to the farm but does not realistically expect to get up to Sparks frequently.

He is looking on the bright side, though.

Despite departing his rural existence and returning to his former life as an urbanite, he relishes in the convenience of being two blocks from Trader Joe’s. Keeping in touch with his penchant for nature, he also said he was pleased that the scenic C&O Canal in Georgetown is within walking distance too.

When he needs a car to leave the Foggy Bottom/West End area, his inner environmentalist shines through.

Just as he practices conservation with food discards, used plates and sheep muck back on the farm, he is committed to staying ecologically friendly in the city as well. Knapp replaced his predecessor’s Lexus SUV with a Toyota Prius hybrid, hoping to save gasoline and make the campus’ air just a bit more like back on the farm.