The mechanization of cleaning or precommercial thinning operations in Sweden first started in the 1980s. Today, used correctly, mechanized cleaning has become a competitive alternative to motor manual cleaning, yet it has not become the most widely used method. There are several reasons for this, including the change in the economical climate which, in recent years, has led to there being a good supply of manual labour. Other reasons are that existing methods are restrained by certain technical limitations; new methods of forest management are creating the need for new machinesystem solutions; and there has been uncertainty in the field over the biological consequences of the method in the long term. How can methods and technology be improved to satisfy the new requirements?
Key words: cleaning, precommercial thinning and mechanization.
Correspondence: Staffan Mattsson, The Forestry Research Institute of Sweden, Glunten, S-751 83 Uppsala, Sweden
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