Just in time to admire Wilton\u2019s autumn colors, Conservation Commission member Donna Merrill will lead a walk through Quarry Head and the Harrison Smith Preserve on Sunday, Oct. 18, at 1. Families and dogs on leashes are welcome for the one-hour walk. Afterward, there will be time for questions and cookies. Although it is managed by the town, Quarry Head is owned by the state. Aptly named, it is the site of Wilton\u2019s first and largest quarry \u2014 mentioned in land records as early as 1739 \u2014 having produced millstones for grinding rye and corn in local gristmills. Later, its stone was used for steps and building foundations, including the granite posts in front of the Schlichting house on Ridgefield Road. The stone was wanted well beyond Wilton. The Singer Sewing Machine Co. in Elizabeth, N.J., used it for the sills and lintels in its factory. It almost became part of the Brooklyn Bridge. According to Bob Russell\u2019s book Wilton, Connecticut, the quarry owners received an order for 350,000 tons of granite for the massive project. Unfortunately for them, delivering the order would have meant having teams of oxen drag the granite from the quarry to the rail station in Wilton Center, a distance of four miles. Given that one team could drag five tons, it would have taken an impossibly long time to fulfill the order. The quarry was known as Millstone Quarry \u2014 giving its name to the nearby road \u2014 and operated for more than 150 years up to the end of the 19th Century. Evidence of the work there \u2014 drill holes and granite ledges \u2014 is still visible. Later, the land was used for residential purposes by the Degener family, who summered there from the late 1920s through the 1980s. A preserved foundation and fireplace are readily apparent from the parking area. The trails allow walks through the park\u2019s lowland and upland habitats. There are impressive views to the south, and on a clear day Long Island Sound can be seen. Deciduous trees include American beech, red oak and tulip poplar. The red trail crosses and then follows Comstock Brook. \u201cI encourage all Wilton residents not to miss this hidden gem,\u201d Merrill told The Bulletin when asked what was special about Quarry Head. \u201cFrom the picnic area, the view across Long Island Sound is spectacular. Then, with a simple turn, one can descend into the forest along a trail that skirts the cliffs of the old quarry to finally emerge into the open meadows of Harrison Smith Preserve. It\u2019s quite an experience!\u201d Adjacent to the 33-acre Quarry Head park is the 23-acre Harrison Smith Preserve. Here are more rock outcroppings and cliffs of gneiss that formed some 400 million years ago. While there was some quarrying done here, it was rather limited, and the land was also used for farming and pastures, with stone walls remaining. The hardwood forest includes some brilliant fall trees: oak, maple, birch, ash, and beech. Healthy yards The day after the walk, Monday, Oct.19, Diane Lewis MD will give a free talk on healthy yards from 7 to 8:30 p.m., at Wilton Library. Founder of the Great Healthy Yard Project, she has written a book by the same name. "With 80 million pounds of pesticides being used on residential lawns in America every year, changing the way we care for our yards is indeed very important,\u201d she said in an email. \u201cThe chemicals that we are putting in our yards are now in every stream, river and lake and half of our well water. Learn how these chemicals get from our yards to our taps, what do they do to us and how. Then learn a surprisingly easy way to fix the problem by working together to chart a happier, healthier course forward for our families with no extra time or money by changing the way we steward our yards.\u201d Lewis is a nephrologist (kidney specialist) and consultant in environmental health. At one time she farmed organically in the High Peaks region of the Adirondacks. She is a board member of the nonprofit organization Bedford 2020 and chairs the Bedford Water and Land Use Task Force. She is also a member of the Bedford Garden Club. Lewis speaks regularly on the impact of water quality on health and writes on matters relating to health and the environment. Her talk is co-sponsored by Wilton Go Green, the Wilton Conservation Commission, the Wilton Garden Club Conservation Committee, and Wilton Library. Registration is recommended. Call 203-762-3950, ext. 312, or visit wiltonlibrary.org.