Tree Shelters Reduced Growth and Survival of Underplanted Red Oak Seedlings in Southern Iowa

Abstract

A major concern in the management of northern red oak (Quercus rubra L.) is the difficulty in regenerating stands that have dense understories of shade tolerant species. A replicated study in southern Iowa indicated that over a 5 yr period, tree shelters have a major impact on establishment of underplanted, 1-0, northern red oak bareroot stock. Sheltered seedlings had increased height growth during the first 3 growing seasons. But during the next 2 growing seasons, annual height growth of sheltered seedlings declined to a level of annual height growth similar to that of nonsheltered seedlings. After 5 growing seasons, sheltered seedlings were approximately 30 cm taller than nonsheltered seedlings. Sheltered and nonsheltered seedlings were one-third to two-thirds the height of the shelters. At the end of the fifth growing season, total mortality for sheltered seedlings was 40 and 55%, whereas for nonsheltered seedlings, mortality was 26 and 28% at the McNay and Stephens sites, respectively. Tree shelters may be a viable alternative in open areas (e.g., clearcuts or plantations), but in this study, tree shelters reduced both growth and survival when used to protect underplanted, 1-0, red oak seedlings. North. J. Appl. For. 16(2):103-107.

Optimizing Hardwood Reforestation in Old Fields: The Effects of Treeshelters and Environmental Factors on Tree Seedling Growth and Physiology

“…This likely led to a reduction of carbon gains in treeshelters (i.e., lower photosynthesis) greater than the reduction of carbon costs (i.e., higher SLA and/or LAR), thus leading to poorer growth in treeshelters than the control. Our results are similar to those of Bardon et al (1999), who attributed growth reductions of underplanted Quercus rubra in treeshelters to insufficient light levels in the understorey. However, light transmission between different treeshelter models is variable (Sharew 2005), and care must then be taken in selecting a proper model for a particular situation.…”

Assessing the effects of stock type and tree shelters on forested wetland restoration in Iowa

“…This is also contrary to results of a number of earlier studies in which shelters enhanced survival largely by protecting seedlings from herbivory (Lantagne et al 1990;Costello et al 1991;Schultz and Thompson 1996;Ponder 2000;Conner et al 2000;Sweeney and Czapka 2004). However, there have also been reports indicating no effect of shelters on seedling survival (e.g., Andrews et al 2010;Stuhlinger 2013;Drayer et al 2017) and other evidence, as in our study, of negative effects from their use (e.g., Bardon et al 1999). Because of the expense associated with tree shelters and their installation, the negative relationship of shelters with seedling survival in our study suggests that they should not be recommended for use on all seedlings in riparian/bottomland restoration plantings unless certain site-specific characteristics (e.g.…”

“…Some researchers have recommended use of more light-transmitting and ventilated shelters that may promote a better balance between height and diameter growth (Sharew and Hairston-Strang 2005). However, other researchers have reported little advantage in terms of survival or growth of sheltered seedlings compared to unsheltered seedlings (e.g., Stuhlinger 2013) that their effect diminishes over time (Drayer et al 2017), or that they actually reduce growth and survival of some species under particular circumstances (Bardon et al 1999).…”

Ecological Factors Affecting White Pine, Red Oak, Bitternut Hickory and Black Walnut Underplanting Success in a Northern Temperate Post-Agricultural Forest

“…The model-K shelter is ideal for underplanting because the large mesh size of the fencing material casts very little shade on the seedling compared to solid or small mesh-size commercial tree shelters developed for afforestation. As shown by Bardon et al [67] the reduction in light availability caused by some commercial tree shelters can reduce the growth and survival of underplanted red oaks. The Model-K shelter can also be slid up on the wooden stake as tree height increases, which eliminates deer browsing of the main stem.…”

“…The type of tree shelter (Model-K) used was well-suited for underplanting because very little light is intercepted by the fencing material (Figures 9b and 10). Smaller mesh size or opaque commercial tree shelters have been found to have little positive effect on white pine in open environments, and to even have negative effects on underplanted red oak [67,97]. Yet, the large mesh size (5 cm) of the fencing material allowed some leaves and branches to grow outside the shelter and therefore be browsed by deer.…”