The Nannen Arboretum Society of Ellicottville recently announced the first of its 2018 educational classes for the general public.

The initial presentation will be given at 6 p.m. Wednesday, March 21 by Tim Baird, a retired science teacher and avid and knowledgeable birder who has a lifelong interest in the geological history of our area. He will present “The Continental Glacier and Cattaraugus County,” which will summarize the glacial period in Cattaraugus County and examine some of the noticeable effects left on the region.

“During the Pleistocene (glacial) epoch, nearly all of New York state was covered by ice. In some regions it was a mile or more thick,” Baird said. “Today there is much evidence showing that the continental glacier impacted the land area that is now New York state.

“Most of Cattaraugus County was ice covered,” he continued. “However, the area to the south and immediately north of the current course of the Allegheny River, including nearly all of Allegany State Park, lay beyond the extent of the ice. Known as the Salamanca re-entrant, it is the only unglaciated part of New York state. Although not directly covered by ice, the region of the Salamanca re-entrant was impacted by the ice to the north.”

Event organizers said those familiar with Zoar Valley and the rocks at Rock City, Panama Rocks and Thunder Rocks may not know all the true details of these areas, as ice helped form lakes and changed the course of the river.

Admission to the glacier presentation is $5 and is payable at the door. The presentation will take place at the Ellicottville Town Center, 28 Parkside Drive in Ellicottville.

Other presentations and activities coming up in 2018 at the arboretum include: an Arbor Day celebration on April 27; Earth Spirit will have a talk on wolves on June 13; open house at the Arboretum on Sept. 23; and a workshop to make wreaths and swags on Dec. 5.