This study describes a simple method to estimate the correlation between root plate tilt and wind speed. The objective was to test if the tilt of trees in high winds can be predicted based on data obtained in the more often occurring low or mid wind events.

Our conclusions are:

  • There is a correlation of wind speed and root plate tilt.
  • The correlation can be described with an e-function or power-function.
  • This best-fit line can be understood as an individual tree’s specific tipping curve
  • Regional wind data can be used to calculate the wind-tilt relation. However, the smaller the distance between tree and weather station is, the better is the result.
  • These wind-tilt curves show the reaction of the tree to the regional wind, including tunneling or sheltering effects of other trees or buildings.
  • The wind direction does affect the wind-tilt curve.
  • Deciduous trees: the variation between summer and winter wind-tilt curve is tree species dependent.
  • Tilt of > 0,2° at wind speed of 50-60 km/h leads to critical tilt values at gale winds.

Further reading

Poster at ISA Annual Conference