Pdf a multifunctional comparison of evenaged and unevenaged. In both systems, trees in the mature forest are evenaged and after the harvest, a new evenaged forest is regenerated. Economics of unevenaged management unevenaged management may be appropriate for certain class of ownership small private landowners some small landowners have a limited land base and wish to obtain periodic returns on investment especially if stand is already unevenaged or twoaged may be too costly to. We suggest reconsidering the current trend of replacing even aged management in temperate forests. The practice of evenaged management is often pursued to minimize costs to loggers. We show that, in addition to the rotation period, economically efficient carbon storage also changes stand density along the rotation and, in many cases, the optimal management regime from evenaged to unevenaged management. A regeneration harvest of an evenaged stand tends to mean a clearcut, but it may.
Naturally regenerated evenaged stands often contain trees of different ages. The declaration against unevenaged management appelroth et al. Uneven aged forests typically have many small trees and very few big trees. More than 40 commercial hardwood species make up the southern hardwood forest. May 12, 2012 since wwii, forest management in fennoscandia has primarily been based on even aged stand management, clear cut harvesting and thinning from below. Unevenaged management a natural approach to timber. Thus, an unevenaged management system may socially or aesthetically beneficial than an evenaged management system. A multifunctional comparison of evenaged and unevenaged forest management in a boreal region. We show that, in addition to the rotation period, economically efficient carbon storage also changes stand density along the rotation and, in many cases, the optimal management regime from even aged to uneven aged management. Efficacy and associated factors of even and unevenaged management to promote oak regeneration in the missouri ozarks.
Despite their accomplishments, unevenaged forest management in north america has largely followed the philosophies of even aged forest management hann and bare 1979. This file was created by scanning the printed publication. Here, we test if beetles using deadwood of different decay stages, and thus with different life histories, respond similarly to silvicultural treatments and if stand. A twostep procedure is commonly used to derive the plan. Unevenaged forest management aims for more heterogeneous stand. Nov 30, 2010 unevenaged management a natural approach to timber. Uneven aged silvicultural approaches are increasingly utilized as efficient management strategies for economic and ecological sustainability of forest resources, including in the southeastern. Unevenaged management up to now, we have dealt almost exclusively with the analysis of evenaged management decisions. We suggest reconsidering the current trend of replacing evenaged management in temperate forests.
The scale of stand disturbance is less than even aged management, although entries into stands may be more numerous retains more mature trees and snags then even aged management results in a more continuous forest canopy which is more aesthetically pleasing than even aged management used for shadetolerant tree regeneration and management. Department of agriculture forest service forest vegetation simulator. Changing philosophies of management have encouraged some landowners to consider converting existing even aged stands to an uneven aged arrangement. These commercial species grow in association with one another and are mixed with an additional 250 species.
Unevenaged stands provide continuous cover on a site, reducing problems with erosion and excessive runoff after heavy rains. With timber prices down for many products, less interest in investing in costly regeneration after harvest, and greater interest in a more natural approach to forest management, many landowners are looking for alternatives to the traditional plant, thin and harvest approach of timber management. Looking at an three aged forest from a diameterclass perspective, the difference between even and uneven aged systems becomes clear. Pdf since wwii, forest management in fennoscandia has primarily been based on evenaged stand management, clear cut harvesting and thinning from. Thus, the actual productivity of unevenaged stands remains largely unknown, even though quantification of the growth rates of beech selection forests at various levels of stand volume has become an important issue for sustainable forest management. Comparing ea and uneven aged forest management in central european beech forests, our results show that a mosaic of different age classes is more important for regional biodiversity than high withinstand heterogeneity. A regeneration harvest of an even aged stand tends to mean a clearcut, but it may. Uneven vs evenaged management in finnish boreal forests.
In this type of forest, young trees will be growing in the. Evenaged and unevenaged forest management in boreal. When the forest was assumed to be under management, any evenaged stand that was not scheduled for clearcutting during an operating cycle was assumed to be commercially thinned. As management treatments have developed, there have also been advances in the development of quantitative tools for unevenaged forestry. Unevenaged stands 2 types balanced irregular unevenaged stand intimate mixture of age classes balanced unevenaged stands allaged forest every age class in the rotation is represented each age class represents approximately the same area regeneration of new trees would need to occur every year balanced unevenaged stands. In any case, there is always a point in the life of an evenaged stand where the majority of an existing forest stand is harvested in order to establish a new stand. Cir 1404 opportunities for uneven aged management in second growth longleaf pine stands in florida1 jennifer l. Cir 1404 opportunities for unevenaged management in second growth longleaf pine stands in florida1 jennifer l. Comparing ea and unevenaged forest management in central european beech forests, our results show that a mosaic of different age classes is more important for regional biodiversity than high withinstand heterogeneity.
What are the effects of evenaged and unevenaged forest. A management planning system for evenaged and unevenaged. When assessing a forests ageclass distribution, however, it is important to. Optimizing the management of unevenaged forest stands. Efficacy and associated factors of even and unevenaged.
At stand level, evenaged management comprises a clear and repetitive cycle of distinct phases, including the regeneration, growing, and thinning, and final harvesting where typically a low number of live retention trees are leaf on the clear cuts. The two evenaged forest management systems in use are clearcut and uniform shelterwood. The selected combination of treatments depends on the conditions of the forest, and the objectives of the forest landowners. A forests value for wildlife management greatly depends on the productivity capacity of the land, the structure of the timber stand, the existing stage of plant growth and the specific wildlife habitat requirements. Unevenaged management up to now, we have dealt almost exclusively with the analysis of even aged management decisions. In even aged stands, most trees belong to snags are standing dead or dying trees that provide nestone age class. Lessons learned smith, exline figure 3simulation of a mixedconifer forest at about 65 percent of full stocking above and 85 percent of full stocking below, by the forest vegetation simulator usda 1996. Evenaged timber management is a group of forest management practices employed to achieve a nearly coeval cohort group of forest trees. Harvest impacts in unevenaged and evenaged missouri.
As management treatments have developed, there have also been advances in the development of quantitative tools for uneven aged forestry. The difference in number of sample treatment plots is a function of the area harvestedbytreatment,i. Looking at an threeaged forest from a diameterclass perspective, the difference between even and unevenaged systems becomes clear. This document is cir 1404, one of a series of the school of forest resources and conservation department, ufifas extension. For herpetofaunal communities figure 3, any kind of forest management, that is, uneven. Timber harvest management even aged and uneven aged forest management are two common silvicultural systems used to produce timber. Evenaged stands never have regeneration, tending, and harvest occurring simultaneously. The impacts of even aged and uneven aged forest management regimes will be compared to each other as well as to forest areas where no intervention has taken place to give a full picture of the impacts. Alternatively, unevenaged management may maintain forest interior conditions but does not provide the largescale heterogeneity created by presettlement disturbance processes. Unevenaged management forest management florida forest. Even aged timber management is a group of forest management practices employed to achieve a nearly coeval cohort group of forest trees. Since wwii, forest management in fennoscandia has primarily been based on evenaged stand management, clear cut harvesting and thinning from below. This will require an extended time as managers partition the cut of original trees in periodically establishing new age classes and maintaining the vigor of ones that develop. It is shown, using examples for northern hardwood stands in wisconsin.
Therefore, artificially planted monocultures and evenaged stands created by schematic silvicultural patterns that are managed for multifunctional. Evenaged and unevenaged forest management in boreal fennoscandia. As an alternative, uneven aged management, based on selection cutting of individual trees or small groups of trees, has been proposed. However, two broad associations were distinguishable, primarily in. Opportunities for unevenaged management in second growth. Maintaining trees of different age classes in the same areacalls for more or less equal, periodic harvestsunder this practice, trees are removed on an individual basis to leave a desired number of trees in each size classvariety of goals can be meteach harvest stimulates reproduction of new trees and enhances the growth and yield of. In some cases, the practices of even aged timber management are frequently implicated in biodiversity loss and other ecological damage. Forest management and ungulate herbivory are extant drivers of herbaceouslayer community composition and diversity. Even before settlers arrived, the domi nant features of these upland forests was their great variety of species.
Harvest impacts in unevenaged and evenaged missouri ozark. The difference between the two systems is the amount of light available for the establishment of regeneration. The traditional choice between even and unevenaged management approaches condemns the landscape to one of two mutually exclusive dynamics, causing the loss of natural. Even aged stands never have regeneration, tending, and harvest occurring simultaneously. We conducted a whitetailed deer odocoileus virginianus exclosure experiment. The declaration against uneven aged management appelroth et al. In finland, for example, evenaged management was the primary management. Silvicultural options to manage forest stands broadly fall into one of two contrasting approaches, namely evenaged or unevenaged management 1,2,3.
To slow down the decline of forest species diversity alternative management regimes have been taken into practice. We evaluated even and uneven aged silvicultural options for slash pine pinus elliottii engelm. As an alternative, unevenaged management, based on selection cutting of individual trees or small groups of trees, has been proposed. A numerical example shows that these two forest management alternatives may exists simultaneously as locally optimal. Pdf evenaged and unevenaged forest management in boreal. Forest management strategy affects saproxylic beetle. Harvest and regeneration methods define each approach. Unevenaged management may be more compatible with many owners financial constraints. Previous research from our study system indicated that evenaged forest management has limited impacts on beetle assemblages compared with unevenaged forest management 24, 25. What is the effect of forest management on boreal forest biodiversity in fennoscandia and european russia at landscape level. Timber harvest management evenaged and unevenaged forest management are two common silvicultural systems used to produce timber. We evaluated even and unevenaged silvicultural options for slash pine pinus elliottii engelm. A multifunctional comparison of evenaged and unevenaged.
This will require an extended time as managers partition the cut of original trees in. Even and uneven aged management scenarios were simulated using the u. Measuring site quality is more difficult in complex stands where freetogrow trees are not present for use in traditional site index measurement berrill and ohara, 2016, fu et al. Uneven aged silviculture and management in the eastern united states proceedings of an inservice workshop morgantown, west virginia july 1517,1975 tim ber management research, forest service u. Even aged and unevenaged forest management in boreal fennoscandia. An illustration of the two forest management systems to be compared in this study. The impact of even aged and uneven aged forest management on regional biodiversity of multiple taxa in european beech forests. The most common scientific approach to numerical landscapelevel forest management planning is combinatorial optimization aimed at finding the optimal combination of the treatment alternatives of stands.
A silvicultural strategy for managing unevenaged beech. Even and unevenaged forest management oklahoma forestry. Data were collected from a mature unthinned slash pine plantation in a flatwoods site in florida, and used to simulate six scenarios of even and unevenaged silvicultural regimes applied to slash pine stands, including a no. When the forest was assumed to be under management, any even aged stand that was not scheduled for clearcutting during an operating cycle was assumed to be commercially thinned. Optimal choice between even and unevenaged forest management systems. This model allows the joint optimization of wood production and carbon storage in uneven aged and even aged forestry. Pdf the choice between even and unevenaged forest management is a topical issue as the negative impacts of clearfelling are being increasingly. Optimal carbon storage in even and unevenaged forestry. An economic comparison of evenaged and unevenaged management of southern pines in the midsouth. The practice of even aged management is often pursued to minimize costs to loggers. An economic analysis of evenand unevenaged management in. Unevenaged forests typically have many small trees and very few big trees. Forest description upland central hardwood types cover more than 27 million acres, twothirds of all forest land in the central states u.
This declaration, which strongly affected forest management in finland for several decades, was not based on any systematic comparison of alternative silvicultural. Uneven aged management in 90 minutes silviculture background forest ecology management tools and stocking control multi aged management regime group selection example single tree selection example tools for assessment and management operations 2. Unevenaged silvicultural approaches are increasingly utilized as efficient management strategies for economic and ecological sustainability of forest resources, including in the southeastern. Evenaged management, as its name infers, involves managing forest stands with trees of a single ageclass, which is typically regenerated either naturally or arti. Abstract for managed temperate forests, conservationists and policymakers. Evenaged management, as its name infers, involves managing forest stands with trees of a single ageclass, which is typically regenerated either naturally or artificially following a clearcut or seed cut. Data from 107 stands, representing a widerange of initial conditions, were acquired from the forest service forest inventory and analysis fia program. Unevenaged silviculture and management in the eastern united states proceedings of an inservice workshop morgantown, west virginia july 1517,1975 tim ber management research, forest service u. Even and unevenaged management scenarios were simulated using the u. Gamma diversity of forest management systems for 15 taxonomic groups in even.
Efficacy and associated factors of even and uneven aged management to promote oak regeneration in the missouri ozarks. In british columbia, unevenaged management has been limited, although interest is increasing. Two perennial problems in the management of unevenaged forests are considered. Maintaining trees of different age classes in the same area calls for more or less equal, periodic harvests under this practice, trees are removed on an individual basis to leave a desired number. Unevenaged management in 90 minutes silviculture background forest ecology management tools and stocking control multiaged management regime group selection example single tree selection example tools for assessment and management operations 2.
Although earlier research produced a substantial body of knowledge to guide evenaged management, less is known about application of unevenaged management methods in longleaf pine forests. The details of applying the same method vary widely because they are altered for each species, forest region, and management objective. At stand level, even aged management comprises a clear and repetitive cycle of distinct phases, including the regeneration, growing, and thinning, and final harvesting where typically a low number of live retention trees are leaf on the clear cuts. May 12, 2012 an illustration of the two forest management systems to be compared in this study. Changing philosophies of management have encouraged some landowners to consider converting existing evenaged stands to an unevenaged arrangement. Diversity was quantified for hill numbers 0 d, 1 d and 2 d, which increasingly weight abundance of species, using sample size. Managing unevenaged stands 25 manage stand density to. In proceedings of the southern forest economics workshop on evaluating even and allaged timber management options for southern forest lands, 2930 march 1990, monroe, louisiana. Retention forestry is usually similar to evenaged management, but some old trees, dead or living, or small stands of trees are retained in harvest to create structural diversity 14, 15. Much of this information is yet in the developmental staage. In fact, positive responses of herpetofaunal species to any kind of logging are rarely observed, especially toward clear. In evenaged stands, most trees belong to snags are standing dead or.
1393 431 563 1330 1290 615 1463 803 164 852 999 478 377 421 1325 62 1328 989 821 1285 441 1365 1479 1467 1232 744 979 414 201 140 869 924 678 492 1253 295 337 561 423 531 123 1062 1221 687 1034 926 1294 1433