Maryland's first split harness racing meeting begins Thursday at Oxon Hill's Rosecroft Raceway, which with Freestate Raceway in Laurel will race 88 nights each this season.

The first part of Rosecroft's meet extends to April 17. Freestate opens April 19 and closes May 22, Rosecroft's second half runs from May 24 through July 15 and Freestate reopens the next night and closes the season Sept. 25.

The split meet became necessary when Laurel Race Course was awarded this year's 48 summer thoroughbred racing dates, which are alternated among the state's major thoroughbred tracks. Laurel will be racing May 24 through July 19, the period the standardbreds usually are at Freestate, so to avoid concurrent meets Rosecroft and Freestate settled on the split schedules.

Ben Schwartz, chairman of the Harness Board of the Maryland Racing Commission, called the split season "the greatest thing that ever happened to harness racing in Maryland" because it will break up the long meets of recent years.

Other changes have been made at Rosecroft.

Thomas Aldrich has become director of administration under W.W. (Pete) Shaw and is expected to replace Shaw as general manager next year when Shaw retires after 20 years at the track. Aldrich's harness background includes work with the Ohio Harness Horseman's Association and Harness Tracks of America.

William E. Miller II was appointed Rosecroft's president in the offseason, replacing Earle Palmer Brown, who became the track's chairman of the board. Miller said the move was made to allow Brown to spend more time with his advertising agency.

Grandstand admission at Rosecroft is $1.50 and gains admittance to the first floor of the enclosed clubhouse. The grandstand itself will be open only on the first three nights of the meet and Saturdays. Post time is 8 o'clock nightly.

The $100,000-guaranteed William E. Miller Pace Memorial, which will have the largest purse ever for a Maryland standardbred race, is scheduled May 29.

Driver Wayne Smullin, 1981 Maryland harness horseman of year, will not be racing here early in the season. He is testing his skills at New York tracks.