Maryland Gov. Martin O’Malley (D) has never needed rural voters to get elected, and for his sake, that’s been a good thing.

O’Malley’s environmental agenda has repeatedly agitated farmers, fishermen, developers and drillers in his nearly five years as governor. Still, the relationship between the former big-city mayor and residents of Maryland’s more conservative countryside has remained mostly cordial.

At least, that is, until now.

“We’re at war. Simply, at war,” Senate Minority Whip E. J. Pipkin (Queen Anne’s) told more than 50 rural — and mostly Republican — lawmakers who gathered last week in the back of an Annapolis restaurant to plot a counteroffensive.

O’Malley has long been unabashedly liberal in his environmentalism and a strong proponent of smart-growth policies. But severalof his initiatives — some of them years in the making — have converged near the policy finish line in recent weeks, riling a broad swath of the state’s rural Republicans, independents and even some conservative Democrats who view his administration’s efforts as government overreach.

The governor has invoked a 37-year-old law to withhold state funding from local governments that fail to curb sprawl. He has proposed a ban on most new septic systems, which critics say will choke off rural development. And he has continued to push for a Chesapeake Bay cleanup that counties warn will cost billions of dollars and untold jobs.

The face-off has opened a new front for O’Malley in advance of a high-stakes General Assembly session that will test his power to eke out wins on controversial measures, including same-sex marriage, costly offshore wind development and higher taxes for transportation.

It also comes as O’Malley is busy preparing for a trade mission to India next month and splitting his time between the governor’s mansion and national fundraising efforts to help elect Democratic governors elsewhere.

“From Annapolis, he’s dictating how communities across the state should develop, and it’s wrong. It’s arrogant,” said Thomas Browning, a Frederick County farmer who attended last week’s meeting.

Alluding to O’Malley’s perceived national ambitions, Pipkin said opponents would seek to “get the word out. . . . He’s at war with rural Maryland,” Pipkin said.

“He just passed a massive toll increase, he’s proposing a gas tax increase, a tripling of the [sewer] tax, and then you add on this power grab over the growth issue.

“Does it really help the governor in his future aspirations . . . to be so abusive to the rural parts of his own state? You tell me: What is the Iowa caucus going to say?”

O’Malley spokeswoman Raquel Guillory said Pipkin’s criticism is misguided.

“The governor, unlike politicians that Pipkin may know, doesn’t make decisions on Maryland’s growth based on politics,” Guillory said. “He is basing his decisions on what is best for Maryland now and in the future.”

The goal of O’Malley’s efforts, she added, is the opposite of what Pipkin and others contend. “These efforts are aimed at reducing sprawl, improving the quality of the bay and protecting the rural areas in Maryland — how is that war?” she asked.

The focal point of most rural residents’ angst is the near completion of O’Malley’s effort to develop a statewide land-use blueprint, known as Plan Maryland.

The master plan seeks to maintain as agricultural or forest land more than 400,000 acres that state planners project would otherwise be developed over the next 20 years. It would do so by targeting development in approved growth areas — most along the Baltimore-Washington corridor. State funding for school construction and other community needs would be used to reward or punish local governments that do or don’t meet targets to create more dense housing and development.

At a hearing in August, O’Malley summarized his view most succinctly: Homes built on two-acre plots with septic systems are sprawl; homes built within city limits on half-acre plots, and in range of sewer hookups, are not. The plan “is not a straitjacket for counties,” O’Malley said. “This is not a wall that prohibits counties from making stupid land-use decisions. They’re still free to do that, but we’re not going to subsidize it anymore.”

The governor maintains that if followed, the plan will reduce by more than $1.5 billion annually the amount the state spends on building roads to new developments, and willcut by hundreds of millions more the amount needed to expand and improve water and sewer systems.

O’Malley is hoping to succeed in codifying such a plan where several previous Democratic governors have failed. He is employing a little-known 1974 law to enact the plan without further hearings or action from the General Assembly, a tactic that has helped stir anger in the state’s rural reaches.

Richard E. Hall, O’Malley’s secretary of planning, emphasized that the plan has been in the works for more than three years and that the administration has extended its period for public comment. The administration has used that public input to shrink the 180-page document by half.

He called it unfortunate that critics have chosen to lump Plan Maryland in with ongoing negotiations over how to reduce septic systems that contribute a disproportionately large share of pollution to the ChesapeakeBay.

Key members of a task force, set up by the General Assembly and the governor after O’Malley’s septic proposal first fell short in the legislature this year, reported last week that to help pay for some of the governor’s proposed septic rules, the task force expects to recommend a doubling — and, eventually, a tripling — of the state’s $30 “flush tax.”

On a separate track, many rural lawmakers are also upset with a multi-state effort known as the Watershed Implementation Plan, or WIP. A Maryland State Builders Association study contends that WIP will cost billions of dollars and tens of thousands of jobs.

“The [critics] have a narrative that they’ve developed — that all of these run together — but we’ve never had anything that ties them together,” Hall said. “For some who want to speak out against and tear down Maryland’s legacy of being a strong smart-growth state, that’s easy for them to do, even though Plan Maryland has been out there for years. It’s been a good punching bag.”

Hall said the administration is moving forward with plans for the governor to enact Plan Maryland next month. Several county executives have urged the governor to wait and let the legislature vote on the plan when it reconvenes in January. And at the meeting last week in Annapolis, Del. Kathy Afzali (R-Frederick) urged a revolt by counties if O’Malley moves forward without legislative approval.

Democratic Sen. Thomas M. “Mac” Middleton, a Charles County farmer, countered that he thinks the governor’s heart is in the right place on Plan Maryland and that a buffer is needed between development and farmland. Buthe said he does not think the legislature is ready to accept O’Malley’s septic plan without major changes.

Many depend on rural residential development for their livelihood, he said. And it should not be up to the state to dictate where communities grow, Middleton said.

“A lot of mouths have to be fed with development,” he said. “You can’t put such a damper on these rural communities.”

The governor’s efforts also have galvanized the state’s tea party. Carroll County has put up thousands of dollars for a summit on Monday featuring internationally known climate-change skeptics andaimed at debunking some of the premises behind Plan Maryland.

“We thought it was worthwhile to get some credible speakers to come and take a look at some of those debatable trends and assumptions,” said Robin Bartlett Frazier, a member of the county’s Board of Commissioners. Also, she said, “there’s an element that has to do with following the Constitution, protecting property rights and free rights.”