Selecting sites for Fraser fir production

Distributed in furtherance of the acts of Congress of May 8 and June 30, 1914. North Carolina Stale University and North Carolina A&T State University commit themselves to positive action to secure equal opportunity regardless of race, color, creed, national origin, religion, sex, age, or disability. In addition, the two Universities welcome all persons without regard to sexual orientation. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating. NC Christmas Tree Notes Selecting Sites for Fraser Fir Production CTN-036 Introduction: Some Fraser fir growers continue to incur costs for site selection decisions that they made years ago. The decision to set a particular field affects all subsequent management activities for the trees on that site, for good or worse. Natural fertility of the soil will determine both the quality of tree growth and the cost of fertility management. Aspect and elevation can influence the incidence of several pests. Clay soils, soil depth to bedrock and/or water drainage patterns can predispose Fraser fir to infection by Phytophthora root rot. While certain management activities can off set the effects of a poor or marginal site, there usually is an increase in the cost and time for production as compared to better sites. By considering a full range of site factors, many problems can be avoided in the site selection process. Elevation and Aspect: Elevation and aspect can define the suitability of a site for Fraser fir, particularly in regard to the climate and soil of that site. The climates of either cold and exposed high-elevation sites (ridges and peaks above 4,500 feet) or very warm low- elevation sites (south-facing slopes below 3,000 feet) can adversely affect Fraser fir root growth, bud set and tree quality. At either extreme, the period of time that tree roots function may be limited. Climate and temperature also largely influence the formation of soil on a site. Organic matter decays and minerals weather faster on wanner sites. Lower elevations and southern aspects generally have less organic matter in the topsoil and more clay in the subsoil than higher elevations or northern aspects. At elevations above 3,400 feet, dark, loam soils can be found at any aspect. As elevation drops below 3,000 feet, aspect becomes more important. At 2,400 feet, a south-facing slope may have too much clay in the subsoil to avoid disease problems where the north face of the same ridge can have a less weathered, loamier subsoil that drains well. Aspect will have a greater influence on steeper slopes than on level ground. Experiencing survival problems associated with Phytophthora root rot (PRR) at low elevation clayey sites, some growers have shifted to high elevation sites. While they greatly reduced the risk of root rot, growers have experiences a different set of site related problems. Climate can be severe. High elevation trees are at greater risk of being whipped by winds, beaten by hail, or pruned by late spring freezes. Well-drained soils may become excessively dry during droughts. High -elevation organic soils have different fertility issues that require individualized management. These potential problems are not insurmountable and do not take the land out of production as PRR would, but can increase production costs and rotation length. Landscape: Farmers have always "read the lay of the land" to help in site selection. This is especially important for Fraser fir, where small changes in soil drainage can make a big difference in the development of Phytophthora root rot. Landscapes (or topography) range between concave areas that collect water and convex areas that shed water. Look for and avoid planting any hollows, gullies, ravines, or dips that indicate intermittent streams or drainage areas. Changes in vegetation can indicate changes in soil type or drainage and can be useful in reading the landscapes. Rushes often indicate wet areas. Patches of green grass STATE UNIVERSITY A&T STATE UNIVERSITY COOPERATIVE EXTENSION Helping People Put knowledge to Work