The Ryland Group Inc., the region's largest home builder, said Monday it is moving its corporate headquarters from Columbia to Southern California after more than three decades in the area.

The company will lay off 100 of its 115 headquarters personnel by the time the move is complete in July 2000.

The long-rumored announcement comes on the heels of a similar move in June by the company's wholly owned mortgage subsidiary, Ryland Mortgage Co., which resulted in about 40 layoffs.

"This has been a difficult decision to make, but one that supports our strategy and growth goals," said R. Chad Dreier, Ryland's chairman, president and chief executive. "It's no offense to this place at all. We just have more opportunities to grow our business out there. I just looked at the numbers."

Ryland, one of the nation's largest home builders and one of Maryland's largest public companies, builds about 1,500 homes a year in California, compared with only 500 in this area. Four of the top 20 housing markets in the country are in California, which is also the national headquarters of several other home builders.

Demographic studies show that western and southern states are gaining population at the expense of the northern and eastern parts of the country.

Dreier said it was "important to be in a key housing market and on the forefront of trends."

The headquarters is expected to locate in Conejo Valley, northwest of Los Angeles.

Dreier, 52, is from Los Angeles, and rumors that the company--founded in Columbia in 1967--could move to Southern California have been around since he took over in November 1993. Dreier said the move wasn't related to his personal preference, pointing out that the board of directors had to approve any relocation. He also denied that the move had anything to do with Maryland's smart-growth policies, of which he has been a frequent critic.

"The growth issue applies in every market," said Dreier, like many home builders an advocate of "managed growth." "It's not any different in California, Texas or Maryland. That did not impact on our decision."

Ryland has more than 2,000 employees nationwide and had $1.7 billion in revenue in 1998.

Maryland officials at the forefront of the state's corporate retention efforts put a brave face on the company's decision.

"I wouldn't characterize it as a big blow," said Maryland Secretary of Business and Economic Development Richard C. Mike Lewin. "We're always sad to lose a headquarters company, but they made this decision on their own specific needs."

Lewin said that he met with Dreier immediately after the announcement and that the Ryland chief was "very warm about how good Maryland has been to the growth of his company."

"They're also going to continue to grow their $100 million a year business here," said Lewin, referring to Ryland's Baltimore-based local operations, which employ 85 people and are not affected by the move.

The company will give the 100 employees who will lose their jobs--mostly staff members in information technology, payroll, accounting, legal and internal auditing--outplacement counseling and packages to assist in their job transitions, the company said. Fifteen corporate staff members will retain their jobs and move with the company to California, Dreier said.

Company officials said the majority of the 40 staff members who lost their jobs in June with the transfer of the company's mortgage subsidiary have found new employment.

"The economic impact of Ryland leaving is not going to be a problem," Lewin said. "We have more than full employment in both Howard and Montgomery counties. Those people will be snapped up."