So many trees, standing out there in forests and fields, and so blatantly visible this time of year without their leaves, as if sunbathing in the nude, so to speak. It makes one wonder what they are — oaks or maples, beeches, sassafras, Northern catalpa, tulip trees — there are so many possibilities. But unlike bathers at a nude beach, the lack of leaves makes it more difficult to assign a classification.

Better call in an expert, or take a walk with one this Saturday, Feb. 20, from 9 a.m. at Polly Hill Arboretum in West Tisbury. From 9 a.m. to noon, curator Tom Clark is offering an introductory class to help identify Island trees, even without leaves for a guide.

The cost is $25 for members, and $30 for nonmembers. Space is limited so call to register at 508-693-9426.