Prince George's County Executive Parris Glendening, rejecting a consultant's recommendation that by the year 2000 the county build an incinerator large enough to burn all its trash, proposed yesterday that the county recycle 25 percent of its solid waste, construct a much smaller plant within seven years and bury remaining trash in landfills.

Glendening, who asked the County Council to act on the proposal by March 1, said he hopes to have pilot recycling programs for paper and aluminum cans in place in six communities by spring. The plan also calls for construction of a recycling plant.

Glendening said that by spring he would recommend two or more proposed sites for the incinerator, with a final decision by the council by early fall. Construction on the plant would begin in 1991 and would cost between $80 million and $120 million.

"I am confident that this program will secure a successful solid waste management system for our future," Glendening said. "I also am confident that these steps put us in the forefront of environmentally aware and responsive solutions to a pervasive local government problem."

Glendening's proposal to build an incinerator that would handle 1,500 tons of waste a day already has drawn criticism from environmentalists on a 24-member public advisory committee Glendening appointed a year ago to study the issue. Critics warned that air emissions and ash residue created from burning trash could create health hazards and said the millions of dollars that would be spent to build the plant could be better spent on a more aggressive recycling program.

"A facility of that size will generate a great deal of ash," said Shannon R. Varner, executive director of the Maryland Public Interest Research Group and a member of the advisory committee.

The county now disposes of its trash in two landfills, Sandy Hill, in central Prince George's County, and Brown Station, near Upper Marlboro in the southern half of the county.