Evaluation of Spectral Light Management on Growth of Container-Grown Willow Oak, Nuttall Oak and Summer Red Maple

Abstract

Plant response to blue, red, gray or black shade cloth was evaluated with willow oak (Quercus phellos L.), Nuttall oak (Quercus nuttallii Palmer, Nuttall) and Summer Red maple (Acer rubrum L. ‘Summer Red’) liners. Light transmitted through the colored shade cloth had no influence on germination of willow oak acorns or height and caliper growth following germination. Tree height, trunk diameter, number of internodes, shoot and root dry weight were generally greater with the species tested when exposed to red or gray shade cloth, but were often similar to plants exposed to blue or black shade. Height increase of willow oak with red shade was similar to plants exposed to blue or gray; however, the average number of internodes was similar with oaks exposed to blue shade and 16% less with oaks exposed to gray shade. Summer Red maples exposed to black, blue or red shade cloth were similar in height, though plants with blue shade had 23% less dry weight. Nuttall oaks exposed to gray shade had the greatest height increase while the plants exposed to red shade had the largest trunk diameter. The growth parameters measured showed some increases with exposure to colored shade, but the morphology of the species tested was not significantly altered to recommend the use of colored shade during production.