
Sweet Sap Silver Maple
The Story of the Sweet-Sap Silver Maple
The Sweet Sap Silver Maple is a project that has been in the works since the 1960s. At that time, H. Cedric Larson, a regional research forester with the Ontario Department of Lands and Forests in Maple, Ontario, found a cultivar of Acer saccharinum with a high sugar content in the sap. It consistently tested somewhere around 3-5% sugar content. He gave some root cuttings to his plant-breeder friends, one of whom was Fred L. Ashworth, the founder of St Lawrence Nurseries in northern NY state. Fred planted the cuttings and they quickly grew into trees. After Fred died in 1977, Bill MacKentley of Potsdam, NY, took over the nursery.
One of the sweet sap silver maples that Fred had planted was on the nursery property. The problem was how to propagate this tree in a way that reliably yielded offspring with the same high-sugar sap. Seedlings would be quite variable. Root cuttings would not yield very many trees. Because of the interplay of root and stem in the yearly process of sap rising, grafting would probably not work; the rootstock would exert an influence over the sugar content.
As tissue culture began to be successful with other species, Bill wondered whether the SSS maple could be propagated by this new method. He finally found a tissue culture lab that was able to reliably propagate the Sweet Sap Silver Maple.
The importance of this cultivar is not as a replacement for sugar maple, but as an addition. Silver maples have more tolerance to wet and/or clay soils. They can be planted on low lands that are not hospitable to sugar maple. They are very fast-growing, becoming tappable in 8-10 years! This particular cultivar has a significantly higher than average sugar content, which means less hauling, and less boiling.
Sweet Sap Silver Maple is sold at 3 - 4 ft. tall.