David M. Hix

Development of mixed-oak forests in southeastern Ohio: a comparison of second-growth and old-growth forests

Abstract Traditionally, studies of forest development have independently focused on the compositional and structural differences of second-growth and old-growth forests. However, few studies have attempted to use current old-growth forest ecosystems as a benchmark with which to compare the composition, structure, and dynamics of a surrounding matrix of sequentially aged second-growth forests. In order to examine the development of mixed-oak forests we compared the composition, structure, and stand dynamics of seventeen relatively undisturbed second-growth forests (70–149 years old) with four old-growth forests (at least 150 years old) on south-facing ecological landtypes (ELTs) in southeastern Ohio. All living and dead trees over 10.0 cm dbh and coarse woody debris over 10.0 cm mid-diameter were inventoried on 500-m 2 plots. Saplings and seedlings were sampled on nested 100-m 2 and 2-m 2 subplots, respectively. Principal components analysis (PCA) was used to support the assumption that study sites had similar soils and physiography. Overstory species richness was greatest in the younger second-growth stands, and significantly differed among age classes. Five species of oaks ( Quercus spp.) dominated the overstories of all stands. However, white oak ( Quercus alba L.) canopy importance value (IV) ((relative dominance + relative density)/2) significantly differed among stands; it ranged from 35.5% in stands 70–89 years old to 86.1% in stands 130–149 years old, while it comprised 46.5% of the old-growth canopies. Pignut hickory ( Carya glabra (Mill.) Sweet.) canopy IV tended to be less in the second-growth than in the old-growth stands. Whereas oaks dominated the overstories of the second-growth and old-growth stands, they were almost absent from the sapling layer of all stands (less than 5% of the total densities). The sapling layers of all age classes were comprised of shade-tolerant species. For example, American beech ( Fagus grandifolia Ehrh.) sapling relative density significantly differed between the 70–89 year old stands (6.3%) and the stands at least 150 years old (23.9%). Even though densities of oak saplings were low, the relative densities of oak seedlings were much greater, suggesting adequate oak advance regeneration. Few significant differences in stand structure (e.g. basal area, density, mean diameter, canopy closure) or standing and fallen coarse woody debris were detected between the second-growth and old-growth forests. Detrended correspondence analyses (DCA) appeared to represent a gradient of increasing white oak IV with age. Although indices of old-growth attributes have proven successful in discriminating between second-growth and old-growth ecosystems in other regions of North America, our results suggest that such an index would not work well in mixed-oak forests. Canopies dominated by a mixture of oaks, in conjunction with a majority of canopy individuals at least 150 years old, may be the best indicators of old-growth conditions on south-facing landtypes in southeastern Ohio.

Pre- and post-European settlement fire history of red pine dominated forest ecosystems of Seney National Wildlife Refuge, Upper Michigan

To understand the dynamics of fire in red pine (Pinus resinosa Ait.) forest ecosystems that once dominated areas of the northern Lake States, we dendrochronologically reconstructed the fire regime prior to European settlement (pre-1860), after European settlement (1860-1935), and postrefuge establishment (post-1935) for different portions (wilder- ness and nonwilderness) and landforms (sand ridges and outwash channels) of the Seney National Wildlife Refuge (SNWR) in eastern Upper Michigan. Using data from 50 sites, we found that the cumulative number of fires showed a slow rate of accumulation from the 1700s to 1859, a steeper pattern suggesting higher fire occurrence from 1860 to 1935, and a return to fewer fires after 1935. Prior to European settlement, the fire cycle (FC) of sand ridge landforms inter- spersed within a poorly drained lacustrine plain in the Seney Wilderness Area was 91-144 years. This was longer than on glacial outwash channel landforms (53 years) and on sand ridge landforms interspersed within lacustrine plains located outside of the wilderness (47 years). The FC was also shorter (30 years) during this period and has subsequently increased (149-1090 years) after SNWR establishment. Differences in fire regimes among landform types were minor relative to the temporal variation in fire regimes among the three time periods.

Defining species guilds in the Central Hardwood Forest, USA

Tree regeneration outcomes are challenging to generalize and difficult to predict. Many tree species can establish new propagules in a variety of post-disturbance environments and many different reproductive mechanisms may be used. In order to develop conceptual models that accurately reflect reproductive potential, we need a better understanding of the similarities in regeneration ecology among species. We used information from the forest ecology literature to evaluate the reproductive attributes of sixty-two tree species in the central hardwood region of the eastern United States. Each species was classified categorically for features such as flowering, seed production and dispersal, seed dormancy, germination requirements, seedling characteristics, and vegetative reproduction. Cluster analysis (Jaccards similarity coefficient, complete linkage method) and ordination (homogeneity analysis) were used to separate nine groups (guilds) of species that had similar reproductive attributes. Individual attributes that had high variance in the first and second dimensions included: seed banking, seed dispersal, seedling shade tolerance, and seedbed requirements. Members of each guild had similar levels of reproductive specialization and guilds were either pioneer-like, opportunistic, or persistent. Pioneer guilds included: short-lived or fugitive species that colonize sites rapidly and are too shade intolerant to replace themselves; shade-tolerant species that colonize frequently disturbed sites; and stress-tolerant pioneers that survive on dry or nutrient-poor sites. Opportunistic guilds contained species that are remarkably versatile in their reproductive effort. The most flexible opportunists can colonize new sites, maintain seed in a seed bank, sprout from existing stems and persist as a seedling or sapling bank. Persistent guilds contain species that develop and maintain advance regeneration. These include: species with moderate understory tolerance that regenerate via cycles of dieback and resprouting; and more tolerant species that maintain seedling or sapling banks. Our regeneration guilds may provide a useful approach for more realistically representing large and diverse sets of tree species in forest ecosystem models.

Central Appalachians forest ecosystem vulnerability assessment and synthesis: a report from the Central Appalachians Climate Change Response Framework project

Forest ecosystems in the Central Appalachians will be affected directly and indirectly by a changing climate over the 21st century. This assessment evaluates the vulnerability of forest ecosystems in the Central Appalachian Broadleaf Forest-Coniferous Forest-Meadow and Eastern Broadleaf Forest Provinces of Ohio, West Virginia, and Maryland for a range of future climates. Information on current forest conditions, observed climate trends, projected climate changes, and impacts on forest ecosystems was considered by a multidisciplinary panel of scientists, land managers, and academics in order to assess ecosystem vulnerability to climate change. Appalachian (hemlock)/northern hardwood forests, large stream floodplain and riparian forests, small stream riparian forests, and spruce/fir forests were determined to be the most vulnerable. Dry/mesic oak forests and dry oak and oak/pine forests and woodlands were determined to be least vulnerable. Projected changes in climate and the associated impacts and vulnerabilities will have important implications for economically valuable timber species, forest-dependent wildlife and plants, recreation, and long-term natural resource planning.

COMPOSITION AND STRUCTURE OF A CHRONOSEQUENCE OF YOUNG, MIXED-SPECIES FORESTS IN SOUTHEASTERN OHIO, USA

Clearcutting, a commonly used silvicultural practice in southeastern Ohio, often results in a forest stand with a different species composition than the parent stand. The time frames during which shifts in species composition occur on different sites are unclear. While some studies have documented species composition at specific points in time, none have attempted to examine differences throughout the first decades of stand development. This study focused on the early successional dynamics of young, mixed-species forests of southeastern Ohio. Species compositions were examined across a chronosequence of sixteen stands that developed following clearcutting. Stand ages ranged from six to 26 years. The sample was limited to dry-mesic hardwood forests on southerly aspects and on soils derived from residuum or colluvium. Across the chronosequence, stand density ranged from 17 636 stems ha-1 at age 6 to 2759 stems ha-1 at age 26, and basal area ranged from 8.2 m2 ha-1 to 22.1 m2 ha-1. Clumps comprised a substantial portion of the total stand density and basal area. At age 6–8 years after clearcutting, clumped stems accounted for 35.1% of the density and 48.2% of the basal area. At age 26 years, these proportions were 25.7% and 29.4%, respectively. Clumped stems were significantly larger (p<0.05) than non-clumped stems at each age group except 26 years. Total Quercus spp. density was greatest at age 6–8 years (3386 stems ha-1), and least at age 26 years (581 stems ha-1). When considered as a proportion of the total stand, however, the proportion was relatively stable, averaging 21.3%. However, importance value (IV=[relative density + relative basal area]/2) of Quercus in the upper canopy (dominant and codominant crown classes) was twice as much (72%) at age 26 years compared to age 6–8 years (35%). Quercus prinus L. was the major species across the chronosequence. For all age groups except 18–20 years. Q. prinus IV was the highest of any individual species in the upper canopy, and it ranged from 27 in the youngest stands (6–8 years) to 69 in the oldest stand (26 years). Within the intermediate crown class, the IV of Q. prinus equaled or exceeded those of all other species, except for the 18–20 year age group where it was second to A. rubrum. Quercus alba L. and Quercus velutina Lam. were minor components at age 26 years, although they dominated a comparison sample of six mature stands of the same ecosystem type. Liriodendron tulipifera L. was abundant 6–8 years after clearcutting, but nearly absent at age 26 years. Acer rubrum L. was the major species in both the intermediate and overtopped crown classes throughout the chronosequence. As gaps in the canopy occur. A. rubrum may become a more common species within the dominant-codominant crown class.

Ground-flora composition and structure of floodplain and upland landforms of an old-growth headwater forest innorth-central Ohio1

Abstract Holmes, K. L., P. C. Goebel (School of Natural Resources, Ohio Agricultural Research and Development Center, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691), D. M. Hix (School of Natural Resources, The Ohio State University, 2021 Coffey Road, Columbus, OH 43210), C. E. Dygert, and M. E. Semko-Duncan (School of Natural Resources, Ohio Agricultural Research and Development Center, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691). Ground-flora composition and structure of floodplain and upland landforms of an old-growth headwater forest in north-central Ohio. J. Torrey Bot. Soc. 132: 62–71. 2005.—We compared the ground-flora (vascular plants ≤1 m tall) composition and structure of floodplain and upland landforms, and examined the influence of environmental factors on ground-flora composition and structure, in an old-growth headwater forest in the Western Glaciated Allegheny Plateau Ecoregion of Ohio. Soil pH, percent organic matter, sand content, and clay content were significantly higher on the floodplains than on the uplands, while the upland landforms were characterized by higher percentages of silt. Percent total nitrogen and concentrations of NO3--N, P, K, Ca, Mg, Mn and Zn were all significantly higher on floodplain landforms than on upland landforms. While species richness and diversity were similar between landforms, ground-flora composition and structure were different. Canonical correspondence analysis (CCA) associated graminoids and forbs with floodplains, while woody species were associated with uplands. Multi-response permutation procedure (MRPP) demonstrated that floodplains had higher cover of Impatiens capensis, Laportea canadensis, Leersia virginica, and Urtica dioica. Conversely, uplands were characterized by higher cover of Acer saccharum, Fagus grandifolia, Fraxinus americana, Parthenocissus quinquefolia, and Polygonatum pubescens. This study provides much-needed information on the vegetation-environment relationships of headwater riparian forest ecosystems that may be useful for riparian restoration in north-central Ohio.

Identifying Land Manager Objectives and Alternatives for Mixed-Pine Forest Ecosystem Management and Restoration in Eastern Upper Michigan

The vast dune system that once dominated the entire western half of the San Francisco peninsula in California has been reduced to a few fragments that conserve locally threatened plant and animal species. We measured the effects of ongoing restoration efforts on wildlife abundance and diversity on one of the largest of these fragments, Fort Funston in the Golden Gate National Recreation Area. Efforts included removal of non-native species, active restoration of native dune vegetation, and restricted visitor use. We collected data regarding the composition and abundance of vegetation, birds, and ground-dwelling vertebrates on four treatments including an actively restored area with restricted visitor use, an unrestored area where visitor use had been restricted for ten years, an unrestored area where visitor use had been restricted for two years, and an unrestored area with unrestricted visitor use. Results indicated that the diversity and abundance of wildlife species, as well as the richness and cover of native plant species, were greater in the restored area than in all other sampled areas. Restricted visitor use alone had only modest positive effects on the abundance and diversity of wildlife and the richness and cover of native plant species.

Annual Change in Ohio Hardwood Stumpage Prices, 1960 to 2011

Abstract Timber price trends provide economic information for forest management and wood utilization decision making, yet to our knowledge, no comprehensive examination of Ohio timber price data ha...

Hazardous fuels management in mixed red pine and eastern white pine forest in the northern Lake States: A synthesis of knowledge

Fuels reduction decisions are made within a larger context of resource management characterized by multiple objectives including ecosystem restoration, wildlife management, commodity production (from timber to nontraditional forest products), and provision of recreation opportunities and amenity values. Implementation of fuels treatments is strongly influenced by their perceived influence on and compatibility with overarching management objectives. In some cases these objectives may be complementary while in others they may involve difficult tradeoffs. Such tradeoffs are only further complicated by institutional mandates, limited availability of information, and complex ownership patterns. Like natural resource managers across the United States, those in the northern Lake States must balance these competing demands as they seek to build their management programs. However, there is limited information available to support these management decisions in the mixed red (Pinus resinosa Ait.) and eastern white pine (P. strobus L.) forests of the northern Lake States. This report informs fuels management decisions in the northern Lake States by synthesizing existing knowledge from the fields of silviculture, forest ecology, wildlife ecology, forest economics, public acceptance, and decision science. We provide an overview of forests and fire regimes in the northern Lake States followed by a description of different fuels treatment techniques and their expected outcomes. We then include a discussion of comprehensive management principles to consider in developing fire and fuels management programs for the region.