Colorado Agricultural Experiment Station
Active Projects 2013

Note: A NEW project—initiated within last year—might not have an annual report, publications, or outcomes/impact.
Project: COL00713 Department: Horticulture & Landscape Arch  
PIs: Klett, JE
Title: Introduction, Adaptability, Production and Survival of Landscape Plants in Colorado
Begin Date: 07/01/2008 Term Date: 06/30/2013 Most recent project status: Terminated
Objectives: 1. Selection, introduction and evaluation of herbaceous annuals, herbaceous perennials and woody plant material for growing in the Rocky Mountain and High Plains Region including Plant Select and native plant material. 2. Conduct cultural studies related to adaptability, production and survival of landscape plants in Colorado which can include: 2A. Weed control studies to aid in overall production of container-grown landscape plants. 2B. Evaluate and determine water requirements of landscape woody plants. 2C. Identify herbaceous plant species and media types for green roofs for use in the semi-arid high elevation Front Range of Colorado.
Approach: Selection, introduction and evaluation of herbaceous plant material for growing in the Rocky Mountain and High Plains region, including Plant Select. Trial planting of annuals, herbaceous perennials, and woody plants will continue to be conducted in Fort Collins to determine which plants are best suited for the Rocky Mountains and High Plains area. Plant Select, a cooperative plant introduction and recommendation program between Colorado State University, Denver Botanic Gardens and Green Industries of Colorado, whose purpose is to increase the diversity of commercially available plants best suited for the Rocky Mountain and High Plains region, will continue to identify, select, test, produce, introduce, and promote outstanding new plants adapted for landscape use. Criteria have been established for identification, selection and testing these outstanding new plants. 2A. Weed control studies to aid in overall production and establishment of landscape plant material. Experiments studying the effect of herbicide types and rates especially with container grown herbaceous perennials and some woody nursery stock will continue. New and standard herbicides and several combinations will be evaluated for their effectiveness and weed control phytotoxicity and effect on plant growth. 2B. Water requirements and abiotic factors of certain woody shrub species is being researched to understand how some species adapt better to certain climatic and cultural conditions in Colorado and the region. The pot-in-pot method is being used to gravimetrically determine plant water loss. In the drought tolerance field study, woody shrubs will be subjected to four different amounts of supplemental irrigation (100 percent, 50 percent, 25 percent and 0 percent of ET) Numerous woody plant species with varying degrees of estimated drought tolerance will be tested. 2C. Green roofs are planted for many reasons, including storm-water management, reducing Urban Heat Island effect and for general aesthetics. Plants native to Colorado, which grow in areas with shallow, well-drained soils are good candidates for green roof plants. Research is needed on additional plant species besides the common sedums to expand the plant palette for green roofs. The modern extensive green roof is based on a design that uses expanded clays and shale. Additional research on media mixes appropriate for green roofs will also be examined. This will become more important as the plant palette for green roofs expands beyond the traditional sedums.
Keywords: plant evaluation Plant Select weed control woody plant production water requirements woody plants green roofs