Organizers: Byung Bae Park (Chungnam National University, Republic of Korea), Palle Madsen (University of Copenhagen, Denmark) & Bryan Finegan (CATIE, Costa Rica)
Forest restoration is more than tree planting: the case of fi re-disturbed southern bog forests. Bannister, J., Bauhus, J.
(University of Freiburg, Germany; janlija@yahoo.com; juergen.bauhus@waldbau.uni-freiburg.de).
Five years ago we commenced a long-term research project on Chiloé Island, North Patagonia, dealing with the study of the ecology and restoration of disturbed southern bog forests dominated by the slow-growing conifer Pilgerodendron uviferum. Using a multi-scaled approach, we focused research on the following questions: 1) can P. uviferum forests persist in the absence of large-scale disturbances; 2) to what extent natural regeneration from seeds of remnant P. uviferum trees may facilitate recoloniza-tion of disturbed forests, and 3) how important are microsite condirecoloniza-tions for successful restorarecoloniza-tion planting of P. uviferum forests?
To answer this, we mapped seed trees in disturbed forests at a landscape level and established seed dispersal, germination, and
active restoration experiments. Our results show that P. uviferum is a stress-tolerant conifer that can regenerate and grow under conditions of low light and low fertility. In disturbed forests, natural regeneration from dispersed seeds of remnant trees can effectively facilitate forest restoration. However, at the landscape scale, after high-severity fi res, there are vast areas without seed trees of the species. In this context, a mixed passive-active restoration approach will be the most effective and effi cient option for the restoration of degraded P. uviferum bog forests.
Achieving “groupy-clumpy” in restoration projects: innovative silviculture and monitoring in the Front Range Collabora-tive Forest Landscape Restoration Project. Dickinson, Y. (Colorado State University, USA; yvette.dickinson@colostate.edu), Colorado Front Range Roundtable Landscape Restoration Team (Front Range Roundtable, USA; gali@behconsulting.com).
Fire suppression during the past century has led to increased density of many lower montane forests of Colorado’s Front Range.
This increased density and canopy contiguity has reduced open-woodland habitat, and may increase the likelihood of large uncharacteristically severe wildfi res and insect outbreaks. These concerns have led to calls for forest restoration to create spatially heterogeneous (“groupy-clumpy”) forest stands with groups of trees, single isolated trees, and openings, and to reconstruct a complex mosaic of forest structure across the landscape. However, the creation of these structurally diverse stands and landscapes has been diffi cult to achieve and monitor using conventional methods. Furthermore, it has been diffi cult to reach a consensus regarding the specifi c desired future conditions in any detail. The Front Range Collaborative Forest Landscape Restoration Project has taken an adaptive management approach to these problems, making iterative improvements to the silvicultural prescriptions and monitoring methods employed. We will present the innovative approaches that the collaboration has developed for implementing and monitoring spatially heterogeneous restoration treatments, and discuss the successes and lessons learned by this project.
Successional trajectories in tropical restored forests using direct seeding of fast-growing species. Engel, V. (São Paulo State University, Brazil; veralex@fca.unesp.br), Parrotta, J. (U.S. Forest Service, USA; jparrotta@fs.fed.us), Nogueira, Jr., L.
(EMBRAPA, Brazil; lauro.nogueira@embrapa.br), Sato, L. (São Paulo State University, Brazil; lu_sato7@hotmail.com), Martins, A. (Usina São Manoel, Brazil; andreza_martins@yahoo.com.br).
In tropical countries, where forest loss is an issue of major concern, cost-effective restoration techniques may facilitate large-scale ecosystem restoration programs. Among low-cost alternatives, some direct seeding methods may promote fast canopy cover and weed suppression. In 1997, we implemented a direct seeding experiment using fi ve fast-growing, light-demanding native tree species in two sites with contrasting soil fertility levels (site 1, red Alfi sol; site 2, red-yellow Ultisol) and landscape context, at Botucatu, São Paulo, Brazil. Initial sowing density was 10 000/ha. While stand canopy density fl uctuated among sites and years, canopy species richness and basal area consistently increased in both sites, from 2.5 to 16 years after implantation. Biomass and net primary productivity also increased with age to 13 years, and slowly decreased thereafter. The number of native species that recruited respectively in site 1 and 2 (height ≥1.30 m) increased from 19 and 34 at 7 years to 64 and 56 at 16 years, while total density increased from 209.3 and 558.8 to 911 and 2 885 in the same sites. During the period, a shift in the canopy dominant species was observed, followed by an increase in the mortality rates of planted species and in the recruitment of native tree species.
A mixed species, clearcut silviculture system to restore native species composition and structure of old-growth forests in western Washington. Ettl, G. (University of Washington, USA; ettl@uw.edu).
The conversion of high-density Pseudotsuga menziesii plantations to more diverse forest species composition and structural attributes, similar to old-growth forests, has received considerable attention. Old-growth forest structure is known to provide habitat to Strix occidentalis and Brachyramphus marmorat, and therefore silviculture to more rapidly advance stand development has been proposed. A prescription known as variable density thinning has been commonly used to facilitate old-growth develop-ment. I describe an alternative multi-species system that begins (and potentially ends) with a clearcut regeneration harvest as a means of producing old-growth composition and structure. I use a conceptual model to present a multi-entry, 300-year rotation aimed at extracting timber, and facilitating multi-layered canopies. Site index and stand density diagrams, in conjunction with conceptual stand development diagrams were used to project an initial multi-species planting of 10 species through time. At regular increments trees are harvested by selecting poor positioned and short-lived species (e.g., Alnus rubra) fi rst and moving toward enhancing large Thuja plicata and Tsuga heterophylla, with lesser volumes of Pseudotsuga menziesii by age 300. The approach will be compared to projections of stands under variable density thinning.
Potential plant functional groups for the restoration of moist forests in the region of Bajo Calima, Colombia. Fernandez Mendez, F. (University of Tolima, Colombia; fmendez@ut.edu.co), Bocanegra-Gonzalez, K. (University of Tolima, Colombia, and Federal University of Lavras, Brazil; kellynda7_7@hotmail.com), Melo Cruz, O. (University of Tolima, Colombia;
omelo@ut.edu.co).
Functional traits of plants show the plants’ succession behavior and serve to break up the complexity of highly diverse tropical forests into groups of potential use for restoration planning. In Bajo Calima, Colombia, where secondary forests are predominant, reproductive traits that indicate the temperament of species in different succession stages were selected. Based on this selection, six groups were determined: 1) large-sized seeds dispersed by birds and mammals; 2) medium-sized seeds dispersed by birds and mammals; 3) small berry fruits dispersed by birds; 4) small seeds dispersed by wind; 5) drupes dispersed by mammals and birds;
and 6) palm species and other species dependent on mammals. It is suggested to use the fi rst two categories in forests that are not heavily degraded, as their species have the potential for active restoration and enrichment; groups 3 and 4 should be used on sites that have suffered more strongly from human intervention as they reproduce easily and are easily dispersed. The two remaining groups are suited for further stages of restoration on sites improved with the fi rst group and on sites that are not strongly degraded. Finally, it is proposed to start reproduction studies for the groups and include them in the restoration processes for the entire Pacifi c region of Colombia and, enrich the suggested methods with local knowledge.
Reintroducing native Fagaceae species into planation forests in central Taiwan: identifying and alleviating establishment limitations. Guan, B., Lo, Y., Li, Y. (National Taiwan University, China-Taipei; btguan@ntu.edu.tw; yuehhsin.lo@gamil.com;
b95605089@ntu.edu.tw), Lin, Y. (Tunghai University, China-Taipei; yichingtree@gmail.com), You, C. (Taiwan Forestry Bureau, China-Taipei; r87625036@ntu.edu.tw).
Developing strategies to restore plantation forests that are either degraded or no longer serving timber production is essential for biodiversity conservation. To facilitate the reintroduction of native late-successional Fagaceae species into Japanese cedar (Cryptomeria japonica) plantations in central Taiwan, we fi rst identifi ed and subsequently experimented with methods to alleviate the establishment limitations. Based on the results from direct sowing of both fresh and germinating acorns, and planting seedlings and saplings of various ages, we identifi ed acorn consumption by wildlife as the most critical factor hindering the establishment. To alleviate the limitation, thinning in combination with ground vegetation control, chemical repellents, and physical retardation methods were tested. Results showed that the most effective strategy is physical retardation, followed by silvicultural treatments. Chemical repellents, such as cinnamamide, commonly used in other areas, had no effect, even in high concentrations, likely because the Lauraceae species are also the native dominants. The results of the study suggest that, although expensive, direct seedling planting or establishing physical retardations to prevent seed consumption will be the most effective strategies. Seedling survival would also be enhanced by the combination of direct sowing of germinating seeds, thinning, and the retention of the understory vegetation cover.
Biodiversity response to trees retained at fi nal harvest for conservation purposes: a meta-analysis. Gustafsson, L., Fedrowitz, K. (Swedish University of Agricultural Sciences, Sweden; lena.gustafsson@slu.se; katja.fedrowitz@slu.se).
Industrial forestry leads to a simplifi ed forest structure and species composition. A main evolving approach to mitigate the impacts of logging on biodiversity is retention of trees at fi nal harvest, and retention forestry is today practiced on several continents in boreal and temperate regions. Numerous studies have been performed on the effects of retention of trees on biodiversity but to date there has been no comprehensive review summarizing the effects on forest species and open habitat species, respectively, compared to open clearcuts as well as forest. We performed a meta-analysis following a systematic review protocol including 653 comparisons between treatment and control from 78 articles. Compared to clearcuts, the effect of retention trees was signifi cantly positive for forest species. When using forests as control, the effect was signifi cantly positive for open-habitat species. Results largely agreed between taxonomic groups. Our fi ndings support retention forestry as a way to moderate logging effects on forest species while at the same time promoting species requiring disturbance. Sensitive forest-interior species as well as some rare disturbance-dependent species will need complementary conservation actions. For regions with a long tradition of industrial forestry, retention forestry is a way to restore the forest landscape.
Improving forest restoration in dipterocarp rainforest: a fi eld trial with 32 native tree species. Gustafsson, M. (Swedish University of Agricultural Sciences, Sweden; malin.gustafsson@slu.se), Alloysius, D. (Sabah Foundation, Malaysia;
dalloysius@gmail.com), Falck, J., Karlsson, A., Gustafsson, L., Ilstedt, U. (Swedish University of Agricultural Sciences, Sweden;
jan.falck@slu.se; anders.karlsson@slu.se; lena.gustafsson@slu.se; ulrik.ilstedt@slu.se).
In the Malaysian state of Sabah (Borneo) most forests outside protected areas have been selectively logged. Many of these forests still hold the potential for high biodiversity and future forest production. Traditionally, forest rehabilitation aimed to increase production and biomass. Today the focus on restoration for biodiversity is increasing, but knowledge concerning tree species survival, growth, and adaptations are limited to a few species. The INIKEA Sow-a-Seed project started in 1998 in Sabah to restore rainforest degraded from logging and wildfi re. The main aim is to improve biodiversity by planting a multitude of native tree species; mainly dipterocarps, but also other climax species and fruit trees. Today, about 100 tree species have been planted on >12 000 ha. In a species fi eld trial experiment we examined survival, growth, and traits among 32 planted native tree species (20 trees/species). We aimed to link tree species responses to site factors to improve predictions of tree species survival and growth. Further we examined if species response to increased light can be predicted by species traits. Preliminary results indicate large differences between the tree species, and that wood density is an important trait, interacting with light intensity to determine individual tree growth.
Biodiversity benefi ts of restoration of boreal forests in Finland. Hekkala, A. (Finnish Forest Research Institute and Thule Institute, Finland; anne-maarit.hekkala@metla.fi ), Tarvainen, O., Päätalo, M. (Finnish Forest Research Institute, Finland;
oili.tarvainen@metla.fi ; marja-leena.paatalo@metla.fi ), Tolvanen, A. (Finnish Forest Research Institute and University of Oulu, Finland; anne.tolvanen@metla.fi ).
Forest restoration is widely used in Finland to bring back essential components typical to natural forests, which have been reduced by effi cient forest management. The structural variety of monocultural conifer stands is increased by adding dead wood and by re-introducing fi re-disturbance, which has been almost eliminated from Fennoscandian forests. We conducted a large scale study on four Natura 2000 protection areas in Finland including three forest restoration methods: tree felling with and without subsequent burning and storm simulation. We studied the effects of these methods on vegetation composition, tree seedling establishment, and tree stand structure. The results of the 7-year study show that tree felling with subsequent burning have considerable effects on vegetation and tree stand structure, enhancing especially deciduous tree seedling establishment. Felling only does not affect vegetation or seedling establishment and the changes in tree stand structure are less substantial. The storm simulation creates patches of exposed soil, initiating vegetation succession and especially pine seedling establishment on these patches and hence causing more heterogeneity on the forest stand. Our results can be used by restoration practitioners or forest managers to decide what methods to use to enhance the diversity of previously managed forest stands.
Restoration of mixed-pine forest ecosystems of eastern Upper Michigan using variable-retention harvesting. Hix, D., Goebel, C., Nyamai, P. (Ohio State University, USA; hix.6@osu.edu; goebel.11@osu.edu; nyamai.1@buckeyemail.osu.edu), Corace III, R. (U.S. Fish and Wildlife Service, USA; greg_corace@fws.gov).
Compared with old-growth mixed-pine forests of the Lake States region of the United States and Canada, many current stands have developed under different disturbance regimes over the past 150 years. Based upon our work in these forests,
we hypothesized that variable-retention harvesting might allow us to both reduce the current live and dead fuels and increase the regeneration of the formerly dominant fi re-adapted tree species (red pine, P. resinosa Ait; and eastern white pine, P. strobus L.).
During 2010, harvests were implemented in the Seney National Wildlife Refuge. In three stands, the basal areas were reduced by 70% leaving a uniform spatial pattern of residual trees and in three stands the basal areas were likewise reduced leaving an aggregate spatial pattern. Two years following harvest, we observed a signifi cant reduction in live fuels and higher densities of newly established eastern white pine seedlings in the treated stands compared to the unharvested control stands. Ordination suggested that fuel characteristics and overstory composition were factors strongly infl uencing the regeneration layer. Stands will be re-inventoried in 2014 to determine the success of these restoration practices, while we also examine the potential to utilize prescribed fi re as a post-harvest treatment to facilitate red pine regeneration.
Additive partitioning approach evaluating the restoration effi ciency of plant species diversity in a warm-temperate mountainous riparian forest in Japan. Ito, S., Asou, H., Hirata, R., Mitsuda, Y. (University of Miyazaki, Japan; s.ito@cc.
miyazaki-u.ac.jp; gb10001@student.miyazaki-u.ac.jp; demian1919@gmail.com; mitsuda@cc.miyazaki-u.ac.jp).
This study examined the effi ciency of different treatments of canopy removal conducted for restoration of the plant species diversity of a riparian forest by using the additive partitioning approach. In conifer plantations along a warm-temperate mountain stream in southern Japan, planted canopy trees were removed with different intensities of logging, small-scale clearcutting, heavy thinning (70%), and light thinning (30%), on different habitats (terraces and slopes). We assessed the species composition of the recovered vegetation in 120 quadrats located in the treated sites including a control. Two-way additive partitioning approaches were applied to evaluate the beta diversities from the aspects of the habitats and the treatments. The results of the habitat-based analysis demonstrated the similar alpha diversities at the quadrat level for each habitat, but signifi cantly higher beta diversity within terraces accounting for 80% of the gamma diversity of the whole area. In contrast, the within-treatment diversity was generally low for every treatment, accounting for only 40% of the gamma diversity by single treatment which left 30% of unrealized richness. These results suggested that the different intensities of canopy removal promoting heterogeneous light environment particularly on terraces are effective to promote the plant species diversity of this riparian forest.
Pioneer species used as nurse crops: a powerful silvicultural method in forest restoration and forest adaptation.
Madsen, P. (University of Copenhagen, Denmark; pam@ign.ku.dk), Stanturf, J. (U.S. Forest Service, USA; jstanturf@fs.fed.us), Nielsen, A. (University of Copenhagen, Denmark; atn@life.ku.dk), Madsen, E. (Skåneskogens Utvecklings AB, Sweden;
emm@skaneskogen.se), Madsen, T. (Store Hjøllund Plantage A/S, Denmark; tlmvrads@post.tele.dk).
The use of pioneer tree species as nurse crops was widespread in the restoration efforts of the degraded lowlands of northwest Europe starting 150–200 years ago. In forest regeneration the method has been commonly used to support regeneration of late successional species on clear-cut sites. The nurse crop species offers shelter against particularly late spring frost and weeds, as well as protection against pests such as weevils or rodents by preventing the site from developing into favourable habitat. The use of pesticides and herbicides gained popularity in forestry following the Second World War and as such largely replaced the nurse crop method. However, today we view the method as even more relevant and needed than before. By using very fast starting species like Populus spp. and Larix spp. the method can greatly elevate forest productivity in the regeneration phase as well as by restoring forest microclimate and forest fl oor conditions. The method seems to pave the road for inexpensive regeneration techniques for a wide range of desired species needed to support forest adaptation capacity on challenging sites. We present results and concepts to foster exchange of scientifi c results and inspiration for further research and development of this method.
Differences in communities of trees along a tropical forest restoration gradient, Uganda. Owiny, A. (Makerere University, Uganda, and University of Eastern Finland, Finland; owinyiarthur@yahoo.com), Valtonen, A. (University of Eastern Finland, Finland; annu.valtonen@uef.fi ), Nyeko, P. (Makerere University, Uganda; pnnyekop@gmail.com), Roininen, H. (University of Eastern Finland, Finland; heikki.roininen@uef.fi ).
Understanding the effectiveness and amount of time required for replanted forests to recover is still a challenge. A critical concern is how well tree communities recover into a more species rich ecosystem. Our study consisted of six restoration forests ranging from 3 to 16 years old and three primary forests. We compared patterns of univariate and multivariate measures of tree communi-ties. We also assessed the recruitment trends of nonplanted, naturally regenerating trees in the restoration areas. Multivariate and univariate analyses of trees showed that recovery responses were generally correlated with age of restoration. Species density, tree density, basal area, and diversity varied but increased with age of planting. The opposite pattern was found in dominance.
Tree community composition showed a directional change; however, communities in the different aged restoration areas had not converged to the composition of primary forests. Restoration planting enhanced natural recruitment of tree seedling. Also, Acanthus pubescens, Lantana camara, and Pennisetum purpureum negatively correlated with species density, tree density, basal area, and diversity. Our results showed that restoration planting can reestablish forests with high species density, tree density, basal area, and diversity, but this is dependent on age and the extent of the herb, grass, and shrub cover.
The importance of silvicultural practices to facilitate forest ecological restoration. Park, B. (Chungnam National University, Republic of Korea; bbpark@cnu.ac.kr), Madsen, P. (University of Copenhagen, Denmark; pam@ign.ku.dk), Finegan, B. (CATIE, Costa Rica; bfi negan@catie.ac.cr), Kim, S. (Korea Forest Research Institute, Republic of Korea; sands02@forest.go.kr).
Both temperate and tropical forests host some of the most widespread and severe examples of forest degradation and
Both temperate and tropical forests host some of the most widespread and severe examples of forest degradation and