Project properties

Title Tree crown development in relation to stand density
Group Forest Ecology and Forest Management Group
Project type thesis
Credits 24-39
Supervisor(s) Etiënne Thomassen, Frits Mohren
Examiner(s) Jan den Ouden
Contact info etienne.thomassen@wur.nl
Begin date 2020/05/01
End date
Description MSc thesis (BSc thesis)
Thinning interventions often aim at crown expansion of the future crop tree that is
released with the treatment. QD Forest management is a novel management
approach aiming to achieve ‘free growth’ of a tree in order to maximize diameter
growth and tree vigour and shorten the rotation. It depends on the strong
allometric relation between DBH and crown size. But this relation is not
independent of stand density/history as trees with small crowns can eventually
reach a high DBH regardless of limited growing space. Verkaik (2020) recently
found in his BSc thesis that angle of the cone of a Douglas fir crown seems to be
a constant variable, with variability in other parameters. If true, this would limit a
trees ability to respond to crown release.
This project revolves around the allometric relation between DBH and crown size
as well as shape in relation to stand density. Ranging from dense forest to open
grown crowns. Do tree crowns posses fixed architecture such as Verkaik’s result
suggest or are they able to truly able to actively fill newly opened space. How
does this differ between abundant Dutch tree species and tree species types (ie
broadleave vs coniferous). Literature study complemented with analysis of
existing data.
https://www.wur.nl/en/project/Optimizing-thinning-for-quality-timber-.htm

Sustainable forest management/ Modelling/ the Netherlands/ Temperate zone/ Desk study
Used skills
Requirements FEM-30306 Forest Ecology and Forest Management and
REG-31806 Ecological Methods I