The Effects of Spacing on the Growth and Yield of Hybrid Poplars (EP 1181)

 Introduction

Poplar density trial - EP1181

Although the silviculture of hybrid poplar is generally understood, there is currently a lack of quantitative information available to identify optimum plantation management regimes for achieving specific yield and product objectives.  In 1995, an experiment was established at the BC Ministry of Forests, Kalamalka Forestry Centre in Vernon, BC in order to determine the effects of espacement (initial density) and rectangularity (within/between row spacing ratio) on the growth, development, and yield of planted poplar. Two similar trials were established in the Chilliwack and Campbell River Forest Disticts in 1994. See map.

Objectives

To determine the effects of espacement (initial density) and rectangularity (within/between row spacing ratio) on the growth, development, and yield of planted poplar.

Treatments

This study uses a non-systematic, "plaid" design that allows spacing to be varied in two dimensions on a factorial basis with a constant number of trees per plot. The distance between rows and the distance between trees within rows are considered as two independent factors associated with each density treatment.  The experiment uses four identical spacings in both dimensions (1.5, 2.25, 3.0, and 4.5 m), resulting in a broad range of initial densities (494 to 4444 trees/ha), and within/between row ratios (rectangularities) of 1:1 to 3:1.  The 16 treatment combinations are allocated to plots of unequal sizes and shapes within each of two rectangular blocks.

This installation is re-measured at 3-year intervals.

Installation Details  (map)

Last Modified: 2007 APR 20.  Ministry contact: Frank van Thienen
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