Sweet baby maples have been cloned and are doing well in the nursery — a greenhouse laboratory, that is, at Cornell University’s Uihlein Foundation Seed Potato Farm, Lake Placid, N.Y. They’re the first buds of a Northeast project to produce rooted “high-sugar” clones for maple producers to plant and enhance sugar-making operations.

“If producers can plant and harvest from trees with naturally higher sugar sap concentrations, productivity would increase and costs would decrease, says Cornell plant pathologist Keith Perry, who conducted the research. “If we can clonally propagate ‘sweet trees,’ there’ll be an opportunity to establish a nursery crop industry as well.”

While trees can be identified for resistance to insects or high-sugar production, trees propagated from seed won’t necessarily have the desired trait, he points out. The only way to get that trait was to propagate them from the “mother” tree by grafting fruit trees and vines. That hasn’t proved practical yet with maple.

In 2014, a research group at the University of Guelph successfully cloned sugar maples by getting tree buds to grow on a sterile media in a laboratory. After Perry visited the Guelph lab in 2016, the Canadian team taught the method at the Uihlein lab, and the cloning project was underway. Research by the U.S. Forest Service and Cornell University had previously identified high-sugar-producing trees in New York and Pennsylvania.

From 433, to 3, to 7
In April 2017, 433 buds were taken from cuttings on higher-sugar maples at the Uihlein Maple Research Station.

After surface-sterilizing, placing them on sterile tissue culture media and a two-month wait, 18 plants had survived. But not all were actively growing. 

As of Dec. 31, three buds — three separate clonal lines — were growing well, and divided into seven plants. Fresh with lessons learned to enhance survivability, plans are already underway to establish additional plant lines from other high-sugar trees.

As an outcome of this investment of the Northern New York Agricultural Development Program, support for continued work in 2018 is being made available through Cornell’s College of Agriculture and Life Sciences. Project results are posted online at nnyagdev.org.

Dunn writes from her farm at Mannsville, N.Y.