A motorist arrested after a wreck that killed six Amish farmers in rural upstate New York pleaded not guilty Friday to aggravated vehicular homicide and manslaughter charges.

Steven Eldridge entered his plea in Penn Yan, his hometown in the Finger Lakes region. The former garbage collector didn't speak during his arraignment in Yates County Court.

The 42-year-old Eldridge also was arraigned on a charge of driving while impaired by drugs, a misdemeanor.

No relatives of the victims or the seven Amish injured in the crash appeared during Eldridge's 15-minute court appearance.

Authorities said his car sideswiped a van carrying 13 Amish farmers from neighboring Steuben County on a Finger Lakes tour on July 19. The Amish van careened into a slow-moving tractor traveling a country road in Benton, 45 miles southeast of Rochester.

Five farmers were killed, and a sixth later died of her injuries.

Police say Eldridge was driving in the town of Benton when he passed the tractor on a curve and ran into a van carrying 15 people, 13 of them Amish who were visiting local farms. Rescuers struggled for hours to free victims from the wreckage lodged under the tractor.

The victims, who ranged in age from 38 to 60, lived in Woodhull and Jasper in southwestern New York, where hundreds of Amish have settled in recent decades.

Killed were Melvin Hershberger Jr., 42; Sarah Miller, 47; Melvin Hostetler, 40; Anna Mary Byler, 60; and Elizabeth Mast, 46. Hershberger's wife, Elva, died several days later.

New York has seen a boomlet in new Amish colonies recently, driven by affordable rural farmland and proximity to traditional population centers. A study by researchers at Elizabethtown College in Pennsylvania found the Amish have established 10 new settlements in New York since the start of 2010. Total population has grown by more than a third in the past two years, to 13,000.