ANNAPOLIS, SEPT. 16 -- Gov. William Donald Schaefer announced the beginning today of a more-than-three-year study of the state's tax structure, immediately sending up red flags in Maryland's wealthiest counties, including Montgomery and Howard.

Schaefer appointed a Montgomery County lawyer to head the project and asserted repeatedly at a news conference that the commission's goal was not to "remove the wealth from one area and put it in another."

Representatives of the wealthy counties, who were briefed about the commission at a breakfast at the governor's mansion, said they took Schaefer at his word but were concerned nonetheless.

"I'm going to watch it very carefully and I told the governor that," said Howard County Executive Elizabeth Bobo, whose county has one of the state's highest per-capita incomes.

"Someone's got to make sure that we {in Montgomery County} don't have any adverse consequences," said Sen. Laurence Levitan (D), chairman of the Senate Budget and Taxation Committee.

Schaefer appointed Silver Spring lawyer and community activist R. Robert Linowes, a former president of the Greater Washington Board of Trade and head of Montgomery County's largest law firm, to head the study.

Linowes was hospitalized Tuesday night for a "mild disorder" and released the next day, and thus was not at the news conference. But he said in a prepared statement that his mission "is far broader and more comprehensive" than previous tax studies.

"The purpose of this commission is not just tax revision, but the matter of spending as well," said Linowes' statement. "It not only seeks to understand what has changed in the past decade, but to chart a course that will enable the state to evolve a better balance between taxation and spending through the remainder of this century and into the next."

Linowes said his commission would hold hearings around the state, authorize studies of the relationship between the state and the subdivisions, investigate whether the state is trying to provide too many services and make interim reports.

He said a full report, including legislative proposals, would be issued by January 1991, after the next elections for governor and the legislature.

Schaefer said the "question of taxation, the question of revenues, the question of expenditures, revenues, needs of various areas have been brought more and more to my attention since I've assumed this office."

He said a comprehensive study is needed, and tried to assuage the worries of wealthy areas that the point of the study was to recommend changes that would result in greater state aid to the state's poorer jurisdictions, such as Schaefer's home of Baltimore.

Experience has shown Schaefer to proceed gingerly on tax matters. He and legislators from wealthier areas of the state clashed during the legislative session over whether a tax windfall resulting from federal income tax changes should be returned to taxpayers or spent on state needs, as Schaefer wanted. The compromise gave most of the money back.

Officials from the state's wealthier areas also say privately that they are worried that the commission appears to be pushed by the Greater Baltimore Committee, a coalition of business people and corporate leaders from the Baltimore area. Committee Chairman Henry Rosenberg and some county executives from counties surrounding the city sent Schaefer a letter asking for the study.