Cloned trees to get big city testing

UPI
Jul. 06, 2006

ITHACA, N.Y., July 5 (UPI) -- Cornell University researchers are partnering with U.S. nursery operators in a project to help trees thrive in harsh urban landscapes.

The scientists, led by Nina Bassuk of Cornell's Urban Horticulture Institute, have developed a new cloning technique called clonal propagation. The technique allows oaks to develop their own root system, rather than growers having to use the difficult grafting method.

Since oaks are nearly impossible to root from cuttings, the researchers have been working with ornamental plant breeder Peter Podaras of the Landscape Plant Development Center in Mound, Minn., to improve the trees' rootability.

They have been crossing deciduous oaks with evergreen oaks and cross-breeding native northern white oaks with white oak species from the Southeast, southern Midwest, North Africa, Asia and the Mediterranean. Some of the 200 combinations of oaks started at Cornell are already 6 feet tall.

"We have combined native cold-hardy trees with much shorter southern and desert species that can tolerate heat, drought, compacted low oxygen soil, road salt and the concrete-induced high pH soils common to cities," Podaras said. "We believe these new extremely vigorous hybrids have excellent potential as the ultimate street trees and for backyard landscaping."