Rubus persistence within silvicultural openings and its impact on regeneration: The influence of opening size and advance regeneration

2018 ◽  
Vol 427 ◽  
pp. 162-168 ◽  
Author(s):  
Mathew J. Widen ◽  
Megan A. Petras O'Neil ◽  
Yvette L. Dickinson ◽  
Christopher R. Webster
Keyword(s):  
2018 ◽  
Vol 75 (3) ◽  
Author(s):  
Jerzy Szwagrzyk ◽  
Zbigniew Maciejewski ◽  
Ewa Maciejewska ◽  
Andrzej Tomski ◽  
Anna Gazda

2008 ◽  
Vol 25 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Kim C. Steiner ◽  
James C. Finley ◽  
Peter J. Gould ◽  
Songlin Fei ◽  
Marc McDill

Abstract This article presents the first explicit guidelines for regenerating oaks in the central Appalachians. The objectives of this paper are (1) to describe the research foundation on which the guidelines are based and (2) to provide users with the instructions, data collection forms, supplementarytables, and decision charts needed to apply the guidelines in the field. The principal research foundation for the guidelines is a set of quantitative models that estimate, in advance of harvest, a stand's potential to regenerate oak stocking from advance regeneration and stump sprouts. Regeneration potential is measured by the predicted stocking by oak species, expressed as a percentage of full (100%) stocking, in the new stand in its third decade (21–30 years) after overstory removal. An understory classification system is used in conjunction with the models to help identifypotential barriers to regeneration development. Model results and other data on current stand conditions are used in the decision charts to identify prescriptions for achieving a strong component of oak regeneration after stand harvest. Overstory removals are recommended when the stand's oak regeneration potential is adequate to meet management goals. Otherwise, prescriptions designed to enhance seedling-origin oak regeneration potential are recommended.


Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 536 ◽  
Author(s):  
Kristen Pelz ◽  
Charles Rhoades ◽  
Robert Hubbard ◽  
Frederick Smith

The severity of lodgepole pine mortality from mountain pine beetle outbreaks varies with host tree diameter, density, and other structural characteristics, influencing subcanopy conditions and tree regeneration. We measured density and leader growth of shade-intolerant lodgepole pine, shade-tolerant Engelmann spruce, and very shade-tolerant subalpine fir regeneration beneath stands that experienced moderate and high overstory lodgepole pine mortality (average 40% and 85% of total basal area) a decade earlier. Lodgepole comprised >90% of the overstory basal area and mature spruce and fir were present in both mortality levels, though live basal area and disturbance history differed. Post-beetle outbreak recruitment was high in both mortality levels, but there were more lodgepole in high than moderate mortality plots (1140 stems ha−1 vs. 60 stems ha−1) and more subalpine fir in moderate than high mortality plots (4690 stems ha−1 vs. 2870 stems ha−1). Pine advance regeneration, established prior to outbreak, was more dense in high mortality than moderate mortality sites (930 stems ha−1 vs. 310 stems ha−1), but the trend was generally the opposite for the other conifers. Lodgepole recruitment increased and subalpine fir decreased with greater forest floor light availability. All species grew faster in high mortality areas than their counterparts in moderate mortality areas. However, in high mortality areas pine grew faster than the more shade tolerant species, and in moderate mortality areas spruce and fir grew faster than pine. These species-specific responses to the degree of overstory mortality will influence future stand composition and rate of forest recovery after mountain pine beetle outbreaks.


1980 ◽  
Vol 56 (2) ◽  
pp. 55-57 ◽  
Author(s):  
L. J. Herring ◽  
R. G. McMinn

The mean height of Engelmann spruce (Picea engelmanni Parry) advance growth 21 years after release by overstorey harvesting and residual tree felling, was eight times that of natural regeneration established following brush blade scarification. Subalpine fir (Abies lasiocarpa (Hook.) Nutt.) advance growth was nine times taller than natural regeneration established on scarified soil. Mean current annual height increment of Engelmann spruce and subalpine fir advance growth was 39 and 34 cm, respectively, compared with only 7 cm for natural regeneration on scarified soil. The performance gap does not appear to be narrowing. The poor performance of natural regeneration on mineral soil exposed by blade scarification is attributed to removal of organic and top mineral soil horizons beyond the immediate reach of seedlings. These soil layers remained available to the advance growth. Consideration should be given to preserving advance growth when scarification may be inappropriate.


1998 ◽  
Vol 22 (1) ◽  
pp. 11-18 ◽  
Author(s):  
James E. Cook ◽  
Terry L. Sharik ◽  
David Wm. Smith

Abstract Despite the large volumes written about "oak regeneration problems" on mesic sites, very little has been presented on the extent of regional variation in oak regeneration. In this review article, we examine several important facets of oak regeneration for the Southern Appalachian region. We conclude that: (1) the amount of reproduction (seedlings and/or sprouts) is seldom a limiting factor because these oak forests have an average advance regeneration density of more than 9000/ha; (2) about 75% of all oak stems sprout after harvesting, which; (3) makes stump sprouts a major source of oak regeneration and a more important component than in the Midwest; (4) harvesting usually leads to an increase in the number of oak seedlings on a site (mean density for the first 3 yr equals 15,750/ha); (5) on sites of SI50 = 17-19m, oaks typically make up 25-40% of the canopy 2-3 decades after a harvest; (6) on sites of SI > 20m, clearcutting leads to very low levels (~10%) of oak representation in the subsequent forest, whereas a shelterwood harvest will result in 25-30% oak abundance; and (7) a harvest of an oak-dominated forest, without any other treatments, will lead to a 50-70% decline in oak. These results suggest that there is ample potential to regenerate current oak forests to oak, but new trials are needed with more species and on a greater range of sites. Increasing the size of the advance regeneration and maximizing stump sprouting are two ways to increase the amount of oak after harvest. However, regeneration cuts by themselves will not assure maintenance of the oak component; several treatments that have shown promise—midstory manipulation, fire, and weeding—are recommended for further study. South. J. Appl. For. 22(1):11-18.


2004 ◽  
Vol 34 (9) ◽  
pp. 1938-1945 ◽  
Author(s):  
Isobel Waters ◽  
Steven W Kembel ◽  
Jean-François Gingras ◽  
Jennifer M Shay

This study compares the effects of full-tree versus cut-to-length forest harvesting methods on tree regeneration in jack pine (Pinus banksiana Lamb.), mixedwood (Picea glauca (Moench) Voss – Populus tremuloides Michx. – Abies balsamea (L.) Mill.), and black spruce (Picea mariana (Mill.) BSP) sites in southeastern Manitoba, Canada. We surveyed tree regeneration densities, disturbance characteristics, and understorey vegetation in replicated control and harvested plots in each site type preharvest (1993) and 1 and 3 years postharvest (1994, 1996). In jack pine sites, the full-tree harvest method promoted regeneration of Pinus banksiana through increased disturbance of soil and the moss layer, and decreased slash deposition relative to the cut-to-length method. Conversely, in mixedwood sites the cut-to-length method resulted in less damage to advance regeneration and proved better at promoting postharvest regeneration of Abies balsamea and Picea glauca relative to the full-tree method. In black spruce sites, there were few differences in the impact of the two harvesting methods on regeneration of Picea mariana, which increased in frequency and density after both types of harvesting.


Sign in / Sign up

Export Citation Format

Share Document