Low density plantings complemented by natural regeneration is an increasingly common reforestation technique to ensure growth of a sufficient number of trees from desired species while maintaining natural processes such as succession. One such form of low density planting that aims at lowering establishment costs—oak clusters—has been developed as an alternative to row planting since the 1980s in central Europe. However, whether cluster planting provides higher species richness and productivity than high density row planting has not previously been analyzed. Here, we compare tree species richness and productivity (measured as stand basal area) between oak cluster plantings and conventional row planting in young (10–26 years old) forest stands at seven study sites in Germany. Tree species richness was significantly higher in cluster plantings than in row plantings, whereas total basal areas were comparable. Naturally regenerated trees contributed on average to 43% of total stand basal area in cluster plantings, which was significantly higher than in row plantings. Total stand basal area in cluster planting was significantly related to the density of naturally regenerated trees. In turn, tree species diversity, density and basal area of naturally regenerated trees were increased with the size of unplanted area between clusters. Our results demonstrate that the admixture of naturally regenerated, early and mid-successional tree species compensates for a possible loss in productivity from planting fewer oaks. Low density cluster plantings can offer significant environmental benefits, at least for the first few decades of stand development, without compromising productivity.
References
[1]
Drouineau, S.; Laroussinie, O.; Birot, Y.; Terrasson, D.; Formery, T.; Roman-Amat, B. Joint Evaluation of Storms, Forest Vulnerability and Their Restoration. Discussion paper 9; European Forest Institute: Joensuu, Finland, 2000; p. 40.
[2]
Gockel, H. Die Trupp-Pflanzung, Ein neues Pflanzschema zur Begründung von Eichenbest？nden. Forst und Holz 1995, 50, 570–575.
[3]
Ehring, A.; Keller, O. Eichen-Trupp-Pflanzung in Baden-Württemberg. AFZ/Dder Wald 2006, 9, 491–494.
Kenk, G.K. New perspectives in German oak silviculture. Ann. Sci. For. 1993, 50, 563–570, doi:10.1051/forest:19930605.
[6]
Larsen, J.B.; Nielsen, A.B. Nature-based forest management—Where are we going? Elaborating forest development types in and with practice. For. Ecol. Manag. 2007, 238, 107–117.
[7]
Fischer, A.; Lindner, M.; Abs, C.; Lasch, P. Vegetation dynamics in central European forest ecosystems (near-natural as well as managed) after storm events. Folia Geobot. 2002, 37, 17–32, doi:10.1007/BF02803188.
[8]
Jonasova, M.; Vavrova, E.; Cudlin, P. Western Carpathian mountain spruce forest after a windthrow: Natural regeneration in cleared and uncleared areas. For. Ecol. Manag. 2010, 259, 1127–1134.
[9]
Puettmann, K.J. Silvicultural challenges and options in the context of global change: “Simple” fixes and opportunities for new management approaches. J. For. 2011, 109, 321–331.
[10]
Bauhus, J.; Schemerbeck, J. Silvicultural Options to Enhance and Use Forest Plantation Biodiversity. In Ecosystem Goods and Services from Plantation Forests; Bauhus, J., van der Meer, P., Kanninen, M., Eds.; Earthscan: London, UK, 2012; pp. 96–139.
[11]
Saha, S. Development of Tree Quality, Productivity, and Diversity in Oak (Quercus robur and Q. petraea) Stands Established by Cluster Planting. Ph.D. Thesis, University of Freiburg, Freiburg, Germany, 23 November 2013.
[12]
Demolis, C.; Fran？ois, D.; Delannoy, L. Que sont devenues les plantations de feuillus par points d’appui? Off. Natl. For. Bull. Tech. 1997, 32, 27–37.
[13]
Szymanski, S. Application of Ogijevski’s nest method of artificial regeneration of oak on fertile sites. Sylwan 1977, 121, 43–55.
[14]
Szymanski, S. Die Begründung von Eichenbest？nden in “Nest-Kulturen”. Forst und Holzwirt 1986, 41, 3–7.
[15]
Gockel, H. Soziale und qualitative Entwicklungen sowie Z-Baumh？ufigkeiten in Eichenjungbest？nden. Die Entwicklung eines neuen Pflanzschemas “Die Trupppflanzung”. Ph.D. Thesis, Georg-August-Universit？t G？ttingen, G？ttingen, Germany, 1994.
[16]
Saha, S.; Kühne, C.; Kohnle, U.; Bauhus, J. Eignung von Nester- und Trupppfl anzungen für die Begründung von Eichenbest？nden. AFZ/Der Wald 2013, 2, 39–41.
[17]
Brang, P.; Bürgi, A. Trupppflanzung im Test. Zürcher Wald 2004, 36, 13–16.
[18]
Brang, P.; Kamm, S.; Mayland, J.-P. Kulturpflege auf Sturmfl？chen: Erhebliches Sparpotenzial. Wald und Holz 2004, 85, 54–57.
[19]
Dong, P.H.; Eder, W.; Muth, M. Eichen-Nesterpflanzungsversuche in Rheinland-Pflaz—Ergebnisse eines 15j？hrigen Beobachtungszeitraums. In Eiche im Pf？lzerwald; Forsschunganstalt für Wald？kologie und Forstwirtschaft Rheinland-Pflaz: Trippstadt, Germany, 2007; pp. 4–22.
[20]
Leder, B. Wachstum und qualitative Entwicklung von Eichennestern. AFZ/Der Wald 2007, 1, 420–423.
[21]
Saha, S.; Kuehne, C.; Kohnle, U.; Brang, P.; Ehring, A.; Geisel, J.; Leder, B.; Muth, M.; Petersen, R.; Peter, J.; et al. Growth and quality of young oaks (Quercus robur and Q. petraea) grown in cluster plantings in central Europe: A weighted meta-analysis. For. Ecol. Manag. 2012, 283, 106–118.
[22]
Rock, J.; Gockel, H.; Schulte, A. Vegetationsdiversit？t in Eichen-Jungwüchsen aus unterschiedlichen Pflanzschemata. Beitr. Forstwirtsch. u. Landsch. ？kol. 2003, 37, 11–17.
[23]
Michéli, E.; Schad, P.; Spaargared, O.; Dent, D.; Nachtergaele, F. World Reference Base for Soil Resources; Food and Agricultural Organization of the United Nations: Rome, Italy, 2006; p. 128.
[24]
Nutto, L. Neue Perspektiven für die Begründung und Pflege von jungen Eichenbest？nden. Ergebnisse einer Untersuchung zur Kronenentwicklung, Astreinigung und Dickenwachstum junger Stiel- und Traubeneichen in Europa. Freibg. Forstl. Forsch. 1999, 5, 147–150.
[25]
Dubravac, T. Regularity of Growth of Crown Structures of Peduncled Oak and Common Hornbeam Depending on DBH and Age in Carpino Betuli-Quercetum Roboris Anic et Raus 1969 Community. Ph.D. Thesis, Zagreb University, Zagreb, Croatia, 15 September 2002.
[26]
Dubravac, T. Developmental dynamics of crown diameters in peduncled oak and common hornbeam related to diameter brest height and age. Rad. Sumar. Inst. 2003, 38, 35–54.
[27]
Piboule, A.; Collet, C.; Frochot, H.; Dhote, J.F. Reconstructing crown shape from stem diameter and tree position to supply light models. I. Algorithms and comparison of light simulations. Ann. For. Sci. 2005, 62, 645–657, doi:10.1051/forest:2005071.
[28]
Vanclay, J.K. Assessing site productivity in tropical moist forests—A review. For. Ecol. Manag. 1992, 54, 257–287, doi:10.1016/0378-1127(92)90017-4.
[29]
Sverdrup-Thygeson, A.; Skarpaas, O.; Odegaard, F. Hollow oaks and beetle conservation: The significance of the surroundings. Biodivers. Conserv. 2010, 19, 837–852, doi:10.1007/s10531-009-9739-7.
[30]
Gotelli, N.J.; Colwell, R.K. Quantifying biodiversity: Procedures and pitfalls in the measurement and comparison of species richness. Ecol. Lett. 2001, 4, 379–391, doi:10.1046/j.1461-0248.2001.00230.x.
[31]
R Development Core Team. R: A Language and Environment for Statistical Computing. 2.14.0; R Foundation for Statistical Computing: Vienna, Austria, 2011.
[32]
IBM. . Version 20; IBM Corporation: Somers, NY, USA, 2012.
[33]
Wohlgemuth, T.; Kull, P.; Wüthrich, H. Disturbance of microsites and early tree regeneration after windthrow in Swiss mountain forests due to the winter storm Vivian 1990. For. Snow Landsc. Res. 2002, 77, 17–47.
[34]
Priewasser, K. Factors Influencing Tree Regeneration after Windthrow in Swiss Forests. Ph.D. Thesis, ETH-Zurich, Zurich, Switzerland, 2013.
[35]
Gockel, H.; Rock, J.; Schulte, A. Aufforsten mit Eichen-Trupppflanzungen. AFZ/Der Wald 2001, 5, 223–226.
