Lamar Advertising Co., billed as the tri-state area's top billboard company, is moving its headquarters to the site of the old Country Belle Dairy, commonly thought to be Green Tree's top industrial eyesore.

"No, that's not an exaggeration," said borough Manager David Montz of the black-windowed, weed-strewn factory on Trumbull Drive that hasn't produced an ounce of milk in some 30 years.

The building best known to Parkway West motorists for its crooked, faded-yellow "Country Belle" sign, he said, has become the wrong kind of Welcome-to-Green Tree landmark.

"I've been employed here for 18 years, and it's been vacant since I've been here," Mr. Montz said with discernible relief. "The neighboring properties have had to endure a lot. Plus, it was right on the parkway and people identified it with Green Tree."

"A lot of people inquired about that building," he said, but its use as a dairy made its configuration difficult to modify. What was needed was somebody with the wherewithal to start from scratch, and without any borough tax break, he said, to sweeten the deal.

"It was going to take somebody like Lamar that had a lot of capital," Mr. Montz said, thrilled by the prospect of having its tax revenue from the property more than double.

The building is assessed at $800,800, according to the county real estate Web site. That added up last year to about $3,400 in borough taxes, plus $17,000 in Keystone Oaks school taxes, Mr. Montz said. The assessment should easily double once the new building is done next fall, he said.

Although Green Tree hasn't had much of a problem attracting office-space developers, Mr. Montz said, landing Lamar to resurrect the Country Belle site is important.

"We've been fortunate to bring a lot of business into Green Tree, but I can't remember who was the last company to come in and buy a single piece of property like this."

Demolition of the building began July 5. Lamar is preparing to move from a century-old building at 2610 Fifth Ave. in Oakland, an isolated stretch that curves just west of Carlow College toward the upper Hill District.

The project is being designed by Renaissance 3 Architects and constructed by Oxford Development Co. It should be finished by October 2007. Plans calls for a one-story, 50,000-square-foot facility including an office building in front and sign shop in the rear.

Stan Geier, vice president and general manager of Lamar Pittsburgh, said making the move was the right one from both ends. In Oakland, highway work to widen Fifth Avenue was going to cost Lamar half of its parking lot. In Green Tree, officials such as Mr. Montz, council members and Mayor Vincent J. Abbato were eager to ease Lamar through the bureaucracy.

"They were excited about a new use, getting rid of that old building," Mr. Geier said. "They were very accommodating and helped us through the permit process and all that. It was very smooth."

In return, Lamar gains "great exposure to major arteries, which would give our company visibility. We have a fleet of 35 trucks that leave our place every day to service 4,000 billboards, so they have to have easy access to get where they need to get to quickly."

The groundbreaking July 27 came 16 months after Lamar bought the property for $1.5 million from a trust held by Andrew Levitske, who had bought the property in 1976, shortly after Country Belle went bankrupt. Mr. Levitske, who died in 2004, left several vacant commercial properties in the county in his estate, Mr. Montz said.

Lamar Pittsburgh is the regional headquarters for a corporation that comprises 160 offices nationwide. Founded in 1902, Lamar Advertising Co. operates in more than 40 states and Puerto Rico. According to its Web site, Lamar services more than 149,000 billboards and has more than 75 transit franchises, including one in Allegheny County that handles displays on bus shelters, benches and buses.