Sugar maple trees showing mysterious decline in growth

Sugar Maple Tree

The rate of growth of sugar maple trees in the New York state has been in decline since the 1970s, says a study published this week in Ecosphere, a journal put out by the Ecological Society of America. The reasons for the decline are not known, but the trend is worrying to scientists.

Sugar maple trees are an important part of the economy and the ecology in the Eastern United States, as well as in Canada. Sugar maples offer high-quality wood, and their sap is used to make maple syrup, which is an extremely important industry in some parts of Canada and the US. While the study only examined trees across the Adirondack Mountains in New York, it seems possible that the decline could also affect trees in nearby Eastern Canada.

“Given their relatively young age and favorable competitive status in these forests, these sugar maples should be experiencing the best growth rates of their lives. It was a complete surprise to see their growth slow down like this,” Daniel Bishop, one of the study’s contributors, told the State University of New York’s Environmental Science and Forestry website. “But our data tells a clear story. We can detect the start of a region-wide downturn after 1970, with a large proportion of the trees continuing this trend over recent years.

“Most tree-ring studies of canopy trees in the region do not show a decline like what we see in these sugar maples,” Dr. Neil Pederson, another of the study’s co-authors, said. “Combined with evidence of reduced natural regeneration of sugar maple in the region, it is a concern.”

While the long-term implications of this study are uncertain, the information it provides will help the syrup and forestry industries adjust to avoid overtaxing the maple population. Foresters and syrup-tappers can use information about maple growth rates to ensure their practices are sustainable.