Regeneration of Northern Red Oak: Positive and Negative Effects of Competitor Removal

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Ecological Society of America is collaborating with JSTOR to digitize, preserve and extend access to Ecology.Abstract. The decreased ability of northern red oak (Quercus rubra) to regenerate throughout its range in the eastern United States has important ecological and economic implications. We studied regeneration of northern red oak in oak and pine stands on moderately productive sites in northern Lower Michigan. Our objectives were (1) to investigate the hypothesis that regeneration of northern red oak is more successful in pine than in oak stands and (2) to test whether removal of potential overstory and understory competitors increases regeneration success on moderately productive sites.Northern red oak acorns and 2-yr-old nursery seedlings were planted in spring 1991 in three natural oak stands and three red pine (Pinus resinosa) plantations on comparable, moderately productive sites. Each stand contained four canopy cover treatments: clearcut, 25% cover (50% the first year), 75% cover, and uncut. Each canopy cover treatment contained four understory treatments: herb-layer removal, shrub-layer removal, litter removal, and control. Seedling survival, performance, and damage due to deer and late spring frosts were quantified along with vegetation characteristics, light, soil moisture, air temperature, soil temperature, and precipitation during the 1991 and 1992 growing seasons. Survival of seedlings was significantly lower in the pine than in the oak stands; the pine stands had a higher incidence of white-tailed deer browsing and lower levels of belowground resources than the oak stands. Canopy cover treatments produced a gradient from high stress (low light and soil moisture) and low disturbance (slight browsing and frost damage) in uncut plots to low stress (high light and soil moisture) and high disturbance (high browsing and frost damage) in clear-cut plots. Understory vegetation developmentand soil temperature were low in uncut plots, high in clear-cut plots, and intermediate in plots with partial overstory removal. Despite poor growth, the mortality of seedlings planted in uncut plots was low. In contrast, mortality was high and surviving seedlings exhibited good growth in clearcuts. Understory treatment effects were slight compared with overstory treatment effects. Results on our sites (1) do not support the hypothesis that regeneration success of northern red oak may be greater in pine than in oak stands and (2) indicate that the positive effects of removing potential competitors on seedling growth and physiological status may be compromised by simultaneous negative effects of browsing and frost damage. Key words: competition; deer browsing; field experiment; frost; n...

In vitro propagation of northern red oak (Quercus rubra L.)

“…The acorns are consumed by insects, deer, and small mammals. Natural regeneration of NRO throughout its range in the eastern USA is difficult because of several factors, such as interspecific competition, predation, disturbance, and reproductive mode (Crow 1988;Steiner 1995;Buckley et al 1998). Acorn production is highly variable (3-to 5-y intervals) and populations of NRO do not produce acorns abundantly until they are 25 y of age (Olson 1974).…”

Impacts of deer herbivory and visual grading on the early performance of high-quality oak planting stock in Tennessee, USA

“…Both containerized seedlings and standard bare-root stock have been employed in post-harvest settings, but have proven unsuccessful in many cases (Hilt, 1977;Loftis, 1979;McGee and Loftis, 1986) due to competing forms of reproduction such as sprouting, especially when site productivity is high (Olson and Hooper, 1972;Russell, 1973). In addition, competition from non-native invasive (NNI) plants and herbivory from whitetail deer (Odocoileus virginianus (Boddaert)) have impeded artificial regeneration success (Gottschalk and Marquis, 1983;Gordon et al, 1995;Buckley et al, 1998;Oswalt et al, 2004).…”

“…Concomitantly, deer browsing has profoundly impacted both the composition and structure of many plant communities, including the depression of natural (Rooney and Waller, 2003) and artificial (Buckley et al, 1998) oak regeneration. In addition, deer herbivory can result in increased seedling mortality (Buckley et al, 1998) and significant impacts on height growth (Oswalt et al, 2004). The aggregate effect is the reduced competitive capacity of planted oak seedlings.…”

Canopy cover effects on nitrogen and phosphorus status in understory vegetation in oak and pine stands

“…Growing-season precipitation and atmospheric temperature, and soil properties were similar at all stand locations in 1991 and 1992 (Kim et al 1996;Buckley et al 1998). …”

“…Changes in soil nutrient and light availability caused by canopy removal could affect nutrient-use efficiency and nutrient uptake of growing vegetation (Covelo and Gallardo 2002). Although several studies have reported on the dynamics of biomass and nutrient distribution of understory vegetation after clearcutting (Ohmann and Grigal 1979;Reiners 1992), information is also needed on how understory vegetation responds to varying degrees of canopy cover because of the increasing use of partial canopy manipulations in forest regeneration (Kim et al 1996;Buckley et al 1998). In this study, we investigated the effects of canopy cover changes on leaf mass, N and P levels in understory vegetation in northern red oak and red pine stands.…”