Containerized tree seedlings will be used on an increasing scale in the future in different parts of the world. There are number of techniques for the production of small one-year-old seedlings but it has not been possible to develop a completely satisfactory methods for large containerized seedlings production. In the long-term development of pine plantations established with containerized seedlings the greatest problem has been deformation of the root system. With a new method, based on a sheet of peat and root pruning, it has been possible to produce conifer seedlings with a good root regeneration potential and favourable morphological root system development. The use of small containerized seedlings allows an increase in planting density without any marked increase in regeneration costs.
The PDF includes an abstract in English.
Because today’s tree planting machines do a good job silviculturally, the Nordic forest sector is interested in finding ways to increase the planting machines’ productivity. Faster seedling reloading increases machine productivity, but that solution might require investments in specially designed seedling packaging. The objective of our study was to compare the cost-efficiency of cardboard box concepts that increase the productivity of tree planting machines with that of today’s two most common seedling packaging systems in southern Sweden. We modelled the total cost of these five different seedling packaging systems using data from numerous sources including manufacturers, nurseries, contractors, and forest companies. Under these southern Swedish conditions, the total cost of cardboard box concepts that increase the productivity of intermittently advancing tree planting machines was higher than the cost of the cultivation tray system (5–49% in the basic scenario). However, the conceptual packaging system named ManBox_fast did show promise, especially with increasing primary transport distances and increased planting machine productivities and hourly costs. Thus, our results show that high seedling packing density is of fundamental importance for cost-efficiency of cardboard box systems designed for mechanized tree planting. Our results also illustrate how different factors in the seedling supply chain affect the cost-efficiency of tree planting machines. Consequently, our results underscore that the key development factor for mechanized tree planting in the Nordic countries is the development of cost-efficient seedling handling systems between nurseries and planting machines.