Cavity trees and coarse woody debris in old-growth and managed northern hardwood forests in Wisconsin and Michigan (original) (raw)
Related papers
Cavity trees, snags, and selection cutting: a northern hardwood case study
Northern Journal of Applied Forestry, 2007
Although traditional application of the selection system includes a focus on high-value trees that may reduce cavities and snags, few studies have quantified those habitat features in managed uneven-aged stands. We examined the effects of single-tree selection cutting on cavity trees and snags in a northern hardwood stand immediately prior to the second cutting. Marking followed guidelines proposed by Arbogast, C, Jr. (1957. Marking guides for northern hardwoods under selection system. US For. Servo Res. Pap.· 56, lake States Forest Experiment Station. 20 p.), with the objective of improving stand quality for timber production while maintaining a balanced diameter. distribution. The stand contained seven species of cavity trees and snags; sugar maple and American beech were most common, the latter comprising 20% of snags and 26% of cavity trees despite its relatively minor (7%) contribution to stand basal area. We found that 92% of cavity trees were live, underscoring the value of living trees as sources of cavities. Precut cavity tree density (25.2 live cavity trees per hectare) was more than twice tnat found in other studies of selection stands, although density of snags (11.0 snags per hectare) was comparable or lower. More than 50% of sampled cavity trees were designated for removal in the second selection cut, reducing projected postcut density to 11.0 live cavity trees per hectare, a density similar to that found in other studies. Postcut density of large cavity trees (3.3 live trees >45 cm dbh per hectare) exceeded published guidelines for northern hardwoods (0.25 to 2.5 live cavity trees >45 cm dbh per hectare). We speculate that the relatively high maximum diameter (61 cm dbh) and long cutting cycle (20 years) used to define the target stand structure may have contributed to the number of cavity trees observed. Nevertheless, selection cutting as applied in this study will likely reduce cavity abundance unless retention of trees with decay is explicitly incorporated into the management strategy.
Canadian Journal of Forest Research, 1999
Coarse woody debris (CWD) chronoscqaences were developed for managed and unmanaged red pine (Pinus to O) to resinosa Air.) stands across the Great Lakes states. Throughout stand development, there is less CWD in managed than to _ _ in unmanaged forests, and effects of management are strongest in young forests (0-30 years old). At stand initiation, •.-t .. CWD is 80% lower in managed than unmanaged forests, 20 200 versus 113 200 kg.ha -t, while at 90 years, CWD is _._ 3_%_ower_66_versus_4_kg_ha_._mbermanagemen_e_pocia1l_a_ectssnags_ungmanag_df_res_s.snag _ biomass is less than 1% of that in unmanaged forests, 150 versus 58 200 kg.ha -I. while log biomass is 80% lower, 5000 versus 22 800 kg.ha -I. This trend continues in mature forests (91-150 years old), where snag biomass is 75% _ lower in managed than in unmanaged forests, 1700 versus 6400 kg.ha -I. Management has relatively little impact on total tog biomass of mature forests but increases the biomass of fresh logs nearly lO-fold, to t400 versus I50 kg-ha -1. CWD in managed forests is highly variable, primarily related to thinning schedules in individual stands. _ R_um_ : Des chronos_uences des d_bris ligneux grossiers om _t_ drvelopt_es pour des peuplements am_.nag_s et non amenages de pin rouge (Pinus resinosa Ait.I duns /es Etats des Grands Lacs. Au tours dn ddveloppement du _ peuplement, il y a moles de d_bris ligneax _ossiers dans les for&s amrnag_es que duns les for_ts non anacnag0,es et _ les effets de l'am,nagemant sont les plus prononc,s dans tes jetmes for_ts (0-30 arts). Au momant de l',tabtissement dd peuplement, il y a 80% moles de drhris ligneux grossiers duns les for_:ts amrnag_es que duns les for_ts non 0,4 amrnag_:es. 20 200 versus 113 200 kg.ha "l. tandis qu'b. 90 arts il yen a 35% de moles. 6600 versus 10400 kg.l_a-t, O _ L'amenagement forestier affecte particulirremem les chicots. Darts les jeanes forrts amrnagres, la biomasse des chicots _/c,J repr_seme moins de 1% de cetle qu.on observe dans les for_ts non am,nag,es. 150 versus 58 200 kg.ha_l tandis qu e la biomasse des billes an sol est 80% plus faible, avec 5000 versus 22 809 kg.ba -]. Ceue tendance se maimient duns _ les for_ts matures (91-150 arts) o_ la biomasse des chicots est 75% plus faible daus les for_ts am_nag,es que darts les _O _ for_ts non am_nag_es. 1700 versus 6400 kg.ha -1. L'am_nagement a relativemant peu d'impact sur la biomasse totale des billes an sol duns les for_:ts matures mats augmente par un facteur de pros de 10 la biomasse des billes an sol dont l'origine esr rrcente, h 1400 versus 150 kg.ha -I. Dans les for_ts am_nag_es, la quemth_ de d_bris ligneux grossiers est tres variable et est principalement reli_:e aux programmes d'¢claircie des peuptements individuels. [Traduit par la R¢dactian] St. Paul. MN 55108, U.S.A the stem-exclusion phase, mortality s re ativelv high but the D.F. Grigal. University of Minnesota, Department of Soil, trees are small so inputs of CWD are similarly small. During Water. and Climate. 439 Borlang Hall. 199l Upper Buford understory remluauon, the rate of overstory mortality slows Circle. St. Paul, MN 55108. U.S.A. but individual clead trees can be large. As the stand moves _Corresnonamg aumor. Current address: Menominee Tribal towards an old*aged conditmn. CWD approaches a "stead.,,' Emerpnses Forestrv Center. Box 670. Kesbena. WI 54135. state. ret]ecung a hypothancal _alance between mortality U,S.A.
Habitat Diversity in Uneven-aged Northern Hardwood Stands: A Case Study
2000
Habitat characteristics were quantified in an empirically balanced uneven-aged northern hardwood stand in central New York. Canopy structure, wildlife trees, downed woody material, low cover, and richness and abundance of understory vegetation were assessed. High vertical structural diversity and low horizontal patchiness were associated with the single-tree selection system. Downed logs and wildlife trees were spatially well distributed, and cavities at a range of heights and sizes were documented. Application of a selection cutting decreased total canopy closure, but maintained high vertical structural diversity and an even distribution of foliage among canopy strata. Cutting reduced the number of wildlife trees, but increased low cover, shade-intolerant understory vegetation, and the abundance and complexity of downed woody material. This study provides quantifiable evidence of the diversity of habitat characteristics associated with a balanced stand structure and uniform spatial arrangement of different sized trees in uneven-aged northern hardwood stands.
Forest Ecology and Management, 1999
The pattern of stand development was studied in two mixed-species single-aged stands that originated after true clearcutting at the Great Mountain Forest in northwestern Connecticut. One stand was located on a mesic swale-till site and the other on a more xeric thin-till site. At the time of cutting all sprout growth and advanced regeneration was eradicated, except for 1-yearold red oak (Quercus rubra) seedlings. Twenty-eight years after the stands originated trees were strati®ed by shade tolerance such that the canopies were dominated by the intolerant species (paper birch Betula papyrifera, gray birch B. populifolia, pin cherry Prunus pensylvanica) with mid-tolerant species (black birch B. lenta, black cherry P. serotina) becoming prevalent. The number of stems was decreasing but the basal area was steadily increasing. The pattern in species-speci®c growth rates and crown position were common to both sites; but there were also differences between the sites in the sizes of trees and positioning of the mid-tolerant trees in the canopy. At age 28 the more mesic swale-till site had fewer, taller trees, with pioneer species more typical of northern hardwood climates. On this site red oak was doing poorly, all gray birch and eastern white pine (Pinus strobus) had died, black birch and black cherry were beginning to dominate the canopy of the stand, and a signi®cant understory of beech (Fagus grandifolia) had developed through the encroachment of root suckers from the stand edge. Sugar maple (Acer saccharum), white ash (Fraxinus americana) and eastern hemlock (Tsuga canadensis), all signi®cant components of the swale-till site before clearcutting, were noticeably absent. On the thin-till site red oak had not attained the canopy of the stand but was still a signi®cant component of the mid-story with red maple (A. rubrum). However, black birch was self-thinning more rapidly on the thin-till site than that of the swale-till suggesting that red oak and red maple might well dominate the canopy within another 20 years. In general, the diameter growth rate of the thin-till site currently lags behind the swale-till by approximately 10 years.
Managing Appalachian hardwood stands using four management practices: 60-year results
Forest Ecology and Management, 2017
A long-term forest management case study on the Fernow Experimental Forest in West Virginia referred to as the Cutting Practice Level study is evaluated after 60 years. Treatments include a commercial clearcut (one time application), a 39 cm diameter-limit (applied 4 times), uneven-aged management using two variations of single-tree selection (applied 7 and 8 times, respectively), and an unmanaged reference area. We examine productivity, species composition and diversity, structure, tree quality, and revenues generated related to each treatment since establishment. The diameter-limit treatment resulted in greatest average periodic annual increment (PAI) of sawtimber volume of 3.1 m 3 ha À1 yr À1 while the unmanaged reference area resulted in the least of 2.2 m 3 ha À1 yr À1 (based on the difference in standing volume from 1956 to 2008). All types of partial harvesting resulted in greater sawtimber productivity than either the commercial clearcut or the reference area. Post-harvest tree quality, as measured by proportion of grade 1 butt logs, has improved from 1988 to 2008 for all but the diameter-limit treatment, which is similar to conditions in 1968. In 2008, the proportion of grade 1 trees in the residual stand ranged from a high of 0.22 for single-tree selection to 0.15 for diameter-limit harvesting. Species composition is becoming less diverse and more dominated by shade-tolerant species in all treatment groups but the change has been the greatest in the two single-tree selection treatments. Initially, size-class distributions were somewhat unimodal and reflective of even-aged stands with shade tolerant species persisting in the understory. In 2008, the single-tree selection treatments were both characterized by a reverse-J size class distribution and it appears this structure can be maintained due to recruitment of shade-tolerant species in the smaller size classes with concomitant reductions in species diversity. The net present value for each treatment in 2008, the time of the last management intervention, ranged from 20,000haAˋ1forreferenceareatoalmost20,000 ha À1 for reference area to almost 20,000haAˋ1forreferenceareatoalmost34,000 ha À1 for the single-tree selection treatment that included management of pole-sized trees based on all revenue and the value of standing timber using an internal rate of return of 4%.
1999
Coarse woody debris (CWD) chronoscqaences were developed for managed and unmanaged red pine (Pinus to O) to resinosa Air.) stands across the Great Lakes states. Throughout stand development, there is less CWD in managed than to _ _ in unmanaged forests, and effects of management are strongest in young forests (0-30 years old). At stand initiation, •.-t .. CWD is 80% lower in managed than unmanaged forests, 20 200 versus 113 200 kg.ha -t, while at 90 years, CWD is _._ 3_%_ower_66_versus_4_kg_ha_._mbermanagemen_e_pocia1l_a_ectssnags_ungmanag_df_res_s.snag _ biomass is less than 1% of that in unmanaged forests, 150 versus 58 200 kg.ha -I. while log biomass is 80% lower, 5000 versus 22 800 kg.ha -I. This trend continues in mature forests (91-150 years old), where snag biomass is 75% _ lower in managed than in unmanaged forests, 1700 versus 6400 kg.ha -I. Management has relatively little impact on total tog biomass of mature forests but increases the biomass of fresh logs nearly lO-fold, to t400 versus I50 kg-ha -1. CWD in managed forests is highly variable, primarily related to thinning schedules in individual stands. _ R_um_ : Des chronos_uences des d_bris ligneux grossiers om _t_ drvelopt_es pour des peuplements am_.nag_s et non amenages de pin rouge (Pinus resinosa Ait.I duns /es Etats des Grands Lacs. Au tours dn ddveloppement du _ peuplement, il y a moles de d_bris ligneax _ossiers dans les for&s amrnag_es que duns les for_ts non anacnag0,es et _ les effets de l'am,nagemant sont les plus prononc,s dans tes jetmes for_ts (0-30 arts). Au momant de l',tabtissement dd peuplement, il y a 80% moles de drhris ligneux grossiers duns les for_:ts amrnag_es que duns les for_ts non 0,4 amrnag_:es. 20 200 versus 113 200 kg.ha "l. tandis qu'b. 90 arts il yen a 35% de moles. 6600 versus 10400 kg.l_a-t, O _ L'amenagement forestier affecte particulirremem les chicots. Darts les jeanes forrts amrnagres, la biomasse des chicots _/c,J repr_seme moins de 1% de cetle qu.on observe dans les for_ts non am,nag,es. 150 versus 58 200 kg.ha_l tandis qu e la biomasse des billes an sol est 80% plus faible, avec 5000 versus 22 809 kg.ba -]. Ceue tendance se maimient duns _ les for_ts matures (91-150 arts) o_ la biomasse des chicots est 75% plus faible daus les for_ts am_nag,es que darts les _O _ for_ts non am_nag_es. 1700 versus 6400 kg.ha -1. L'am_nagement a relativemant peu d'impact sur la biomasse totale des billes an sol duns les for_:ts matures mats augmente par un facteur de pros de 10 la biomasse des billes an sol dont l'origine esr rrcente, h 1400 versus 150 kg.ha -I. Dans les for_ts am_nag_es, la quemth_ de d_bris ligneux grossiers est tres variable et est principalement reli_:e aux programmes d'¢claircie des peuptements individuels. [Traduit par la R¢dactian] St. Paul. MN 55108, U.S.A the stem-exclusion phase, mortality s re ativelv high but the D.F. Grigal. University of Minnesota, Department of Soil, trees are small so inputs of CWD are similarly small. During Water. and Climate. 439 Borlang Hall. 199l Upper Buford understory remluauon, the rate of overstory mortality slows Circle. St. Paul, MN 55108. U.S.A. but individual clead trees can be large. As the stand moves _Corresnonamg aumor. Current address: Menominee Tribal towards an old*aged conditmn. CWD approaches a "stead.,,' Emerpnses Forestrv Center. Box 670. Kesbena. WI 54135. state. ret]ecung a hypothancal _alance between mortality U,S.A.
Distribution of cavity trees in midwestern old-growth and second-growth forests
Canadian Journal of Forest Research, 2003
We used classification and regression tree analysis to determine the primary variables associated with the occurrence of cavity trees and the hierarchical structure among those variables. We applied that information to develop logistic models predicting cavity tree probability as a function of diameter, species group, and decay class. Inventories of cavity abundance in old-growth hardwood forests in Missouri, Illinois, and Indiana found that 811% of snags had at least one visible cavity (as visually detected from the ground; smallest opening [Formula: see text]2 cm diameter), about twice the percentage for live trees. Five percent of live trees and snags had cavities on mature ([Formula: see text]110 years) second-growth plots on timberland in Missouri. Because snags accounted for typically no more than 10% of standing trees on any of these sites, 8085% of cavity trees are living trees. Within the subset of mature and old-growth forests, the presence of cavities was strongly relat...
Northern Journal of Applied Forestry, 1996
Five Central New York northern hardwood stands were regenerated by clearcutting method, and followed through 20 yr of development. Observations from permanent remeasured plots indicate that a closed canopy formed and completely shaded the ground by 10-15 yr. Data gathered before that time did provide general information about features like the proportion of area stocked with trees and the stem density. After canopy closure, no new species entered the stand. Yet the actual species composition continued to change throughout the 20 yr period. Additional changes will occur as relatively short-lived species like striped maple, pin cherry, and aspen die. For other species, the change of importance will continue to depend on differences in their growth rates and tolerance to shading. Collectively, these dynamics will likely prolong the relatively rapid shifting of species composition for at least one-third to one-half of a century. Such findings suggest that the onset of canopy closure mar...
Wildlife implications across snag treatment types in jack pine stands of Upper Michigan
Forest Ecology and Management, 2018
Standing dead trees, or snags, represent post-disturbance biological legacies in forest ecosystems, and intentional creation of new snags is increasingly common during forest treatments. The abundance, volume, size, and distribution of snags can affect wildlife communities and stand-level biological diversity. Characteristics such as the wood properties of different tree species, environmental conditions, and cause of tree death (e.g., insects, disease, senescence, wind, fire) can influence decomposition and subsequent use of snags by wildlife. The objectives of this study were to characterize decay patterns in jack pine (Pinus banksiana) snags that had been killed by prescribed fire, topping, and girdling and determine the effects of these treatments on subsequent snag use by subcortical insects and primary cavity-nesting birds. The prescribed fire, topping, and girdling treatments were implemented in 2003, 2004, and 2007, respectively; bird excavations were quantified in 2014 and insect activity was measured in 2016. One-way analysis of variance tests were used to examine any differences among treatments in snag characteristics, decay characteristics, past insect activity, and past use by birds. An information theoretic approach to model selection was then used to rank potential predictors of bird foraging activity and cavities. The topping treatment had unique decay characteristics relative to the other two treatments; topped snags had the highest levels of past insect colonization, were softer, and had higher proportions of loose bark remaining on the boles. Trees killed by prescribed fire had the greatest number of foraging excavations and cavities. Girdled snags had the lowest evidence of past insect colonization and showed different levels of decay and insect use at different vertical positions on the snag bole. Comparison of candidate models showed that a model containing treatment type alone was the highest ranked when predicting foraging by birds, while snag diameter was the highest ranked when predicting the presence of cavities. A model containing treatment and snag density was also a highly ranked for predicting cavity presence. Our findings suggest that different jack pine snag treatments result in unique decay trajectories that may influence snag use by an array of wildlife taxa. Our characterization of three snag creation treatments can also inform options for generating snags, depending on the desired outcome, when management for biological legacies and wildlife habitat is of interest within mixedpine forests of the Great Lakes region. 1. Introduction Dying trees, standing dead trees (snags), and downed woody material have numerous ecological functions and contribute to structural complexity and biodiversity within forests (Harmon et al., 1986, Franklin, 1988). For example, dying trees increase availability of resources such as light, nutrients, and water, and provide structure and food for a wide range of taxa (Franklin et al., 1987). A diversity of fungi, plants, and animals utilize snags and downed wood throughout their life cycles (
Coarse woody debris in managed central hardwood forests of Indiana, USA
2004
We evaluated the volume of down deadwood (DDW) and the basal area of standing deadwood (SDW) from a chronosequence of 110 silvicultural openings and 34 mature stands (72-105 years old) across three Ecological Landtype Phases (ELTP; wet-mesic bottomlands, mesic slopes, and dry-mesic slopes) in southern Indiana, USA. The volume of DDW decreased with increasing opening age and was lower in clearcuts than in group-selection openings. Openings on mesic slopes and bottoms contained greater volumes of DDW than openings on dry-mesic slopes. Regardless of age and ELTP, openings contained low volumes of highly decayed DDW. The volume of small-diameter DDW decreased rapidly with increasing stand age across all three ELTPs. Mature stands contained low total volumes of DDW (maximum of 22.4 C 5.1 m3 ha I ) and low volumes of both highly decayed and large-diameter DDW. Most of the dead trees in silvicultural openings were small diameter and did not contribute significantly t o DDW volume. SDW basal area was very low in mature stands (maximum of 1.4 2 0.5 m 2 ha I ) , suggesting that little mortality has occurred. Our results suggest that even and uneven-aged silviculture in hardwood forests have differing impacts on the volume and distribution of coarse woody debris (CWD). In addition, the mature stands that dominate forests across much of the Central Hardwood Region of the eastern United States contain relatively little CWD compared to younger and old-growth stands. FOR. SCI. 50(6):781-792.