Agroforestry Systems

, Volume 16, Issue 2, pp 167–175 | Cite as

Tree planting pattern effects on forage production in a Douglas-fir agroforest

  • S. H. Sharrow


Resource sharing among agroforestry system components, as expressed by spatial patterns along interfaces between components, is a crucial factor in both understanding present systems and in designing new agroforestry applications. A study of the spatial pattern of forage production surrounding 9–10 year old Douglas-fir trees in a agrosilvopastoral plantation near Corvallis, Oregon, was conducted during 1988 and 1989. Transects of plots were clipped both between trees (tree/tree) and between trees and open pastures (tree/pasture). Best-fit regression models relating forage production to distance from trees (tree/tree R2 = 0.87; and tree/pasture R2 = 0.89) were combined into a single prediction model. Observed forage production increased rapidly with increasing distance from trees during the initial 4 m. Trees had little effect on forage production beyond 4.5 m (approximately 2 canopy diameters) from the nearest tree. Predictions of different combinations of tree density and planting pattern indicated a strong interaction between density and pattern with highly aggregated plantations better able to maintain forage production at high tree densities.

Key words

agrosilvopastoral sheep conifer clover competition 


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Copyright information

© Kluwer Academic Publishers 1991

Authors and Affiliations

  • S. H. Sharrow
    • 1
  1. 1.Department of Rangeland ResourcesOregon State UniversityCorvallisUSA

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