| Summary: | Afforestation is increasingly receiving global interest, not only for ecosystem restoration purposes, but also for carbon sequestration. This is also true in Iceland, which witnessed devastating periods of deforestation and land degradation and is now increasing its efforts in creating new woodlands. In ecological and economic terms, it is however questionable, whether planting trees is more effective than direct seeding. To investigate differences, between both methods, several woodland creation trials were set up in South and East Iceland in the 1990s. A total of 12 establishment methods have been tested on four tree species, including native birch and non-native conifers. The objective of this study is now to better understand the feasibility of these different methods through a qualitative supply chain analysis and their biological outcomes. More than two decades later, all upcoming trees were assessed in terms of survival, height and further growth criteria. Lodgepole pine proofed to be the only species, with a sufficient survival rate in all trials. Apart from one trial planted pines always performed better than seeded. However, within the direct seeding methods, including a seed-shelter and slow-release fertilizer had a significant effect (p<0.005), both on the survival rate and height growth of lodgepole pines. Regarding supply chain costs, afforestation by direct seeding entails only 30 % of the costs associated with planting. Although further studies on species interaction, seed predation control and management costs are still needed, woodland creation with directly seeded lodgepole pine can be regarded a viable addition to current planting efforts. Nýskógrækt nýtur vaxandi hylli á heimsvísu til að auka og endurheimta skógarvistkerfi, auk kolefnisbindingar. Þetta á við á Íslandi þar sem átt hefur sér stað mikil skógareyðing og landhnignun af mannavöldum, en aukin áhersla er nú lögð á að rækta nýja skóga til fjölbreyttra nota. Spurningar hafa vaknað hvort sé skilvirkara til þess að rækta nýja ...
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