Like many Republicans in Pennsylvania, Richard Alloway believes in smaller government, the sanctity of the Second Amendment and the promise of natural gas drilling in the Marcellus Shale.

But the GOP state senator representing South Central Pennsylvania also believes in clean water. He has planted thousands of trees across his district, pushed for more funding for farmers to help them curb their runoff, and is working on a bill to regulate the fertilizing of lawns.

Elected in 2009, Alloway said he has always been an environmentalist; he grew up hunting and fishing in Pennsylvania’s vast outdoors. But his appointment to the Chesapeake Bay Commission two years ago solidified his commitment to the estuary and spurred him to push for more legislation to protect it.

“You can be a conservative and be pro-environment,” Alloway said during an interview in his Chambersburg office. “What’s the heart of the word conservative? It’s ‘conserve.’”

Until a few decades ago, Alloway wouldn’t have stood out. Republicans helped build the Bay cleanup movement and pushed for clean air, clean water and preservation of natural areas. Theodore Roosevelt and John D. Rockefeller Jr., scion of the Republican political family, were forces, nationally, in conserving some of the United States’ most cherished landscapes. Charles “Mac” Mathias, Jr., a three-term U.S. senator from Maryland, was instrumental in crafting the first Chesapeake Bay Agreement. The Nixon administration established the Environmental Protection Agency, albeit somewhat reluctantly, and imposed a ban on DDT in 1972 amid concerns about the pesticide’s impact on birds and possibly on human health.

In recent years, one of the most powerful Republicans in the U.S. Senate has brought a snowball to the chambers in an attempt to disprove global warming. Most of the GOP candidates for president this year have questioned whether climate change is real, and said if it is, it’s unlikely that humans are causing it. The Pennsylvania Farm Bureau enjoyed broad support among Republican state legislators in its failed court case accusing the EPA of overreach for trying to enforce its Baywide cleanup plan, known as the Total Maximum Daily Load.

It’s a lonely job, the role of a conservative Republican pushing for environmental improvements. Alloway acknowledges it can be tough pleasing the members of his caucus as well as his conscience. (He does believe climate change is real, and that human activity is accelerating it, but he’s not sure it’s happening as fast as recent predictions claim.)

Bay advocacy is especially hard in Pennsylvania, which contributes the largest load of pollution to the Chesapeake but has no Bay frontage. Complicating matters is Pennsylvania’s history as an extraction state. The first oil wells were drilled in Pennsylvania. It has also yielded large quantities of coal, natural gas and timber.

Though many of Alloway’s constituents drive across the Bay Bridge en route to the beach, relatively few have made the connection between their actions on land and water quality, he said.

Given Pennsylvania’s recent budget battles, residents are loath to spend money on an expensive cleanup that they don’t think will benefit them. Many of the farmers contributing to the Bay’s pollution are Plain Sect or Amish, who won’t take government money or accept high-tech solutions that change the way they’ve farmed for generations. But Alloway suggested that it’s precisely because of who he is that he’s poised to make a difference.

“I’m sort of an interesting spokesman, which is why I take this role so seriously,” he said. “I think I’m the guy who can bridge the gap between the left and the right. Let’s lower the rhetoric. Let’s talk about what we can agree on, and what we can get done.”

One recent morning, Alloway was up at 7 a.m. to help plant 1,500 trees at a military base. Superstorm Sandy had sheared the mountainside, and the federal government had helped to pay for replacements. He’s already on pace to beat last year’s record of 3,000 trees planted in his district, which includes Hanover, Gettysburg and Chambersburg.

Alloway said he always knew trees had benefits, but his service on the commission showed him just how far behind his state — once known as “Penn’s Woods” — had fallen in reforestation. Trees, Alloway reasoned, are a low-cost solution to a multitude of problems. They suck up nitrogen, cool the air, improve habitat for fish, dampen noise from highways and beautify communities. They also offer an easy way to involve the community and engender its thanks.

“Rich has really embraced the idea of planting trees to help the watershed. Given his stature as a state senator, it really helps to get the message out,” said G. Warren Elliott, a fellow Bay Commission member who has known Alloway since he was a teenager. Alloway once took a local government class taught by Elliott at Shippensburg University. Elliott, a business consultant who serves on Pennsylvania’s Fish and Boat Commission, has become a mentor of sorts to the 48-year-old senator.

“He’s connected the dots in his own mind that if we’re going to hunt and we’re going to fish, we also have to protect the resources,” Elliott said.

Through his work on the commission, Alloway has been pushing for more funding to keep livestock out of streams. As with the trees, he said, it’s an easy solution that makes a big difference.

A harder sell, he said, has been a fertilizer bill that he hopes will reduce the amount of phosphorus entering waterways. The bill would require commercial fertilizer applicators to get certified, and it would codify Penn State recommendations to restrict spreading lawn food on frozen ground or less than 10 feet from waterways. Maryland passed similar legislation. Alloway said he heard about it through his commission work and decided Pennsylvania should try something similar.

As he presses his causes, Alloway is hoping the work becomes less lonely.

“I think that my generation, and the next generation, of Republicans are going to have to be pro-business and pro-environment,” he said. “The future of the Republican Party is a conservative and environmental-minded official.”