Tree Shelters Improve the Survival and Growth of Planted Engelmann Spruce Seedlings in Southwestern Colorado

Abstract

Shade-tolerant Engelmann spruce (Picea engelmannii) is a difficult species to reforest successfully in the high-elevation spruce-fir forests of the Rocky Mountains. This study investigated the use of plastic tree shelters as a form of shade protection and a means to improve the growth and survival of planted Engelmann spruce seedlings in southwest Colorado. A total of 1500 seedlings were planted into a 48 ha clearcut site at an average elevation of 3273 m. Treatments included four different colors of tree shelters and a control where seedlings were planted using the traditional shading method. This consisted of shading the seedlings using logging slash, stumps, and vegetation within the site. After two growing seasons, survival was 58% for the control treatment and ranged from 95 to 99% in the lighter three shelter color treatments. The darkest shelter color resulted in 95% mortality after the first growing season. Both height and diameter growth of surviving seedlings were significantly greater in the lightest two shelter color treatments as compared to the control treatment. These results indicate that tree shelters may provide an effective method of improving high-elevation Engelmann spruce reforestation programs. West. J. Appl. For. 16(3):114–120.

Restoration planting options for limber pine (Pinus flexilisJames) in the Southern Rocky Mountains1

“…Large rocks on the landscape may indicate rocky areas with shallow rocky soil that prevents digging and may negatively impact seedling survival. Jacobs and Steinbeck's (2001) success with artificial shelters and Ronco's (1970a) success with shingles to protect Picea englemannii seedlings in the central and southern Rocky Mountains indicates that plastic shelters or wooden shingles may be a viable option for use in protecting planted P. flexilis seedlings as well. While these shelters have the possible drawback of introducing artificial materials into the landscape, they solve the problems caused by planting near naturally occurring objects.…”

“…We did not carry out an operational planting trial, so future planting trials are needed where seedlings are planted operationally. In the future, studies are necessary that consider larger sample sizes and longer durations of monitoring, greater elevation ranges, greater diversity in canopy densities including clearcuts, alternative nurse objects such as tree shelters (Ronco 1970a, Jacobs andSteinbeck 2001), and various other factors. These future studies will further our understanding of microsite characteristics, the longterm influence of canopy cover on seedling maturation and survival, and nurse object factors that are important for natural P. flexilis regeneration, continuing to expand on the work of Coop and Schoettle (2009).…”

“…In planting studies of Picea englemannii Parry ex Engelm. (Engelmann spruce), nurse objects have been beneficial for seedling survival (Ronco 1970a;Jacobs and Steinbeck 2001). These objects provide protection from the sun; increase snowpack, which protects seedlings from cold temperatures; increase soil moisture; and may enhance mycorrhizal infection (Callaway and Walker 1997;Germino, Smith, and Resor 2002).…”

Effect of tree shelters on the survival and growth of coniferous tree species in Central South Bulgaria

“…They have also been used to create a favourable microclimate for growth and to protect seedlings from herbicide application (Kays, 1995). Compared to the open air, light access is lower in tree shelters, but CO 2 , temperature, and relative humidity increase (Jacobs and Steinbeck, 2001).…”

A climate adaptation strategy for conservation and management of yellowcedar in Alaska

“…Solid-walled tree shelters are an alternative to Vexar that can withstand high snow loads and improve survival and growth of seedlings(Devine and Harrington 2008, Jacobs andSteinbeck 2001). Even though solid tubes perform better in environments that receive heavy snowfall, it is still recommended that periodic maintenance of the tubes occur.…”