Woody Plant Research at the W. D. Holley Plant Environmental Research Center


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National Elm Trial

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The main objectives of this demonstration garden are to determine which woody plants are best suited for growing in the Rocky Mountain area and display these plants for public and teaching purposes.

The arboretum at PERC has the largest collections of woody plants in the region with over 1,100 different taxa represented. Presently, a computerized method for collection, storage, and retrieval of information on plant performance has been implemented for all the woody plants in the arboretum. This year, 55 different woody plants were donated from eight different nurseries, arboreta, USDA, and other state experiment stations for evaluation. All new bare root woody plants were containerized after arrival. Shrub and tree species obtained this year are growing in our lath house and/or greenhouse and eventually will be planted in the various collections. Also, 57 different cultivars of crabapples were planted in a replicated experiment at our Horticulture Research Center in 1984 as part of a national program for evaluating crabapples for fireblight resistance and 13 newer varieties were added in the spring of 2004.

PERC arboretum in the fall.

The woody plant section is designed on a grid pattern, and exact permanent locations of plant material have been determined and recorded. Most plants in the arboretum are labeled, and each plant label has a trial selection number, along with scientific and common names listed on it. Display labels with scientific and common names have been placed on one replication of each taxa throughout the arboretum this year on the north side of the plant.

In the southeast corner of the arboretum, a Plant Select® demonstration garden is planted. In this planting current and future woody and herbaceous Plant Select® endorsements, introductions or original plants are planted. Plant Select® is a joint plant introduction program between Colorado State University, Denver Botanic Gardens and the Green Industry of Colorado.


Arboretum in Winter

The woody plant demonstration/research area is under the direction of Dr. James E. Klett. David Staats (Research Associate) is in charge of record keeping for this area in 2008.

In the spring of 2003, we lost approximately one and one half acres of the arboretum for the construction of a new dormitory on campus. The approximately 120 taxa of plants located in this area were tree spaded to a new arboretum site off of Center Avenue, north of Spring Creek and adjacent to the new City of Fort Collins horticulture center (The Gardens at Spring Creek). These trees are planted in rows by genus at the new site. In the Spring of 2005 seventeen different Elm cultivars were planted in order to find varieties that may be more resistant to Dutch Elm Disease. This is one site in the National Elm Trial program. Feel free to visit this site and view first-hand these newer tree clones.


Arboretum in Spring

Arboretum in Summer



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