Plant Sciences

Accessibility


| Share

Woody Plant Improvement Program Celebrates 60th Plant Release

The 60th woody plant release from the NDSU Woody Plant Improvement Program led by Dr. Todd West was introduced by the North Dakota Agricultural Experiment Station and the North Dakota State University Research Foundation. KoolKat™ Katsura Tree is a single plant seedling selection originating from a population of Cercidiphyllum japonicum acquired in 1999 from the Lesny Zaklad Doswiadgzalny W. Rogowie Arboretum in Rogów, Poland. A unique characteristic is its early fall dormancy, which aids in increasing its winter hardiness.
 
 

December 2, 2020

A new woody plant selection, KoolKat™ Katsura Tree (Cercidiphyllum japonicum ‘KoolDak’), was introduced by the North Dakota Agricultural Experiment Station and the North Dakota State University Research Foundation. This is the 60th new plant release developed by the NDSU Woody Plant Improvement Program led by Dr. Todd West.

KoolKat™ is a single plant seedling selection originating from a population of Cercidiphyllum japonicum acquired from the Lesny Zaklad Doswiadgzalny W. Rogowie Arboretum in Rogów, Poland. Seed was acquired in 1999 and designated as TS9946. The trees in this population were part of the NDSU Woody Plant Statewide Cooperative Evaluation Program that ran from 1987 to 2007. 

KoolKat™ is a cold-hardy selection that has survived without damage in USDA climatic zone 3a at temperatures as low as -37 degrees Fahrenheit. This single plant selection is unique in that it has early fall dormancy compared to the species, which aids in increasing the winter hardiness. All other traits are similar to the species, with cordate (heart) shaped leaves emerging reddish-purple in the spring and changing to blue-green as they mature for summer. In autumn, fall color is yellow to apricot in color depending on the year. 

KoolKat™ is dioecious and is a female selection, possessing only female flowers. Mature height will be 35 to 40 feet with a width of 20 to 25 feet.

About the NDSU Woody Plant Improvement Program

The NDSU Woody Plant Improvement Program has been serving the Northern Great Plains for over 65 years, beginning germplasm trial evaluations in 1954. In 1974, NDSU purchased 80-acres near Absaraka, ND, and the NDSU Horticulture Research Farm was established. Trial plantings began immediately that fall. This research farm provides ideal horticultural soil for evaluation and breeding projects for North Dakota. Approximately 45 acres of the farm are used for the evaluation, selection, and breeding of woody ornamental plants.

The center portion of the research farm is a 35-acre plot known as the Dale E. Herman Research Arboretum. Named after NDSU Professor Emeritus Dale E. Herman, who developed the program for nearly 40 years, the research arboretum is the most extensive collection of woody ornamental plants in North Dakota and the northern Great Plains. It is a valuable resource for teaching, research, and educational use.

NDSU woody plant introductions are currently being propagated for sale by commercial wholesale firms in Australia, Canada, England, and 35 nurseries in 14 of the United States. This project has introduced 60 superior woody plants for production and sale with increased disease tolerance and winter hardiness for landscapes. The first introduction from the program in 1986 was a flower bud hardy Forsythia hybrid, ‘Meadowlark’, which was a collaborative release with South Dakota State University, Arnold Arboretum of Harvard University, and the USDA North Central Regional Plant Introduction Station.

In 2012, several breeding programs were initiated focusing on magnolia, lilac, maple hybridizing, and mutagenic breeding of several shrub species. The NDSU Woody Plant Improvement Program also serves as the northern site for the American Rose Trials for Sustainability (A.R.T.S), launched in spring 2014.

The goals of the NDSU Woody Plant Improvement Program are selection, evaluation, and introduction of hardy superior woody plants for the landscape industry. For more information about the program, visit www.ag.ndsu.edu/plantsciences/research/woody-plants/.

Author: Dr. Todd West ()
Editor: Kamie Beeson ()

Creative Commons License
Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.