Der internationale Douglasien-Provenienzversuch in Hessen : Ergebnisse bis zum Alter 27 : Results up to age 27

The international Daouglas fir provenance trial in Hesse

Alfeld

2005

8 Abb., 8 Lit. Ang.

Artikel aus einer ZeitschriftUnselbständiges Werk

4354

200124700

Results of assessments in seven Hessian trials of the IUFRO Douglas fir provenance experiment (104 provenances from 14 regions) are presented. Until age 27 of the plants the best provenances in respect to growth, straightness, branchiness and needle damage come from Vancouver Island, Olympic Peninsula, Puget Sound and the Western Cascades in Washington. Volume growth per hectare of these provenance regions may be two or three timer higher than growth of interior regions. Differences between the best and worst single provenances are even more significant and cannot be compensated by silvicultural measures. In order to guarantee long term procurement with seed Hesse has established seed orchards and future seed stands with proved original provenances. Besides this, we are testing progenies of our own stands, and we are started a program to check all the douglas-fir stands of the state forests between 20 and 40 years old according to a list of criteria characteristic for maladapted provenances. We know from earlier studies that such provenances are to be found especially among stands of the second age class.