On Thu, 3 Nov 1994 11:10:43 +0200 buergi wrote: > From: buergi <buergi@wsl.ch> > Date: Thu, 3 Nov 1994 11:10:43 +0200 > Subject: Re: Costs and Benefits of Exotics > To: forest@nic.funet.fi > > The discussion about the introduction of exotics is almost as old as forestry > on a scientific basis. . . . > The criteria for plantations of exotic species in Switzerland could be > summarized as follows: > - the species shall be adapted to the site conditions and should not be > endangered by pests and dieases (no chemical treatment in Swiss forests) > - exotic species shall grow in mixed stands with indigenous species > (no big scale pure plantations of one single species) > - growth performance shall be better than for the indigenous species > - the timber shall have qualities, which can not be met by indigenous species > > But the most important criteria is the silvicultural risk. Indigenous species > showed since thousands of years, that they can live with the properties of > the respective site. Since forests in Switzerland are not only producing > timber, but have often an important protective function, minimizing the risks > in forestry is a predominant task. And the risks with exotic species are > higher than with indigenous species. Examples are C. ribicola at P. strobus > and needle casts at Douglas Fir. > Now these are criteria I can live with! Exotics without significant threat to ecological systems . . but this as about as different from Australian plantation forestry as native forest is from intensive agriculture. > A. Buergi > WSL > CH-8903 Birmensdorf > . Dr Don Ewart D.Ewart@ForProd.CSIRO.Au Granitgard Pty Ltd/CSIRO Div. Forest Products Mail: Priv. Bag 10 Rosebank MDC, Clayton VIC 3169, Australia Tel: +613 542 2271 Fax: +613 543 6613 Finger: 138.194.54.125 URL: http://www.mps.ohio-state.edu/cgi-bin/hpp?Termite.html The opinions expressed above are not those of CSIRO or Granitgard .
Mail converted by
MHonArc 1.1.0