Nitrogen and Sulphur Fertilization of Interior Conifers (EP 886.01c)

Introduction

This series of area-based field installations was initiated in 1992 in order to expand the species and biogeoclimatic zone coverage of area-based fertilization installations in the B.C. interior. A total of 31 field installations in this series have been established to date. The installations are distributed among three species (16 Pl, 9 Sx, 5 Fdi) and six biogeoclimatic zones (SBS, MS, SBPS, ICH, IDF, and ESSF). Based on strong evidence of S limitations in interior forests, all of the installations test both N and N+S fertilization. Installations are located within plantations and in fire- and harvest-origin stands, and ranged in age from 18 to 44 years old at the time of installation establishment.

Objectives

To determine the effects of nitrogen, with and without added sulphur, on the growth and development of interior conifer species.

Treatments

In most installations, three replicates of each of three treatments (unfertilized, 200 kg N/ha, 200 kg N/ha + 75 kg S/ha) are arranged in a completely randomized or a randomized complete block design. At three sites, a "Complete Mix" treatment (N, P, K, Mg, S, B) is added to the core design to test for other growth-limiting nutrient deficiencies. Treatment plots are circular, and vary in size from 0.06 to 0.14 ha depending on plantation or post-thinning density of the stand. Each treatment plots consists of an inner assessment plot surrounded by a treated buffer. Growth data (diameter at breast height, total height, height to live crown, tree form and damage) are collected from 50 trees within each assessment plot.

All of the installations will be re-measured at 3-year intervals for 12 years and at 6-year intervals thereafter. Foliar nutrient data are obtained from all treatment plots prior to fertilization and after 1 and 3 years.

Publications

The National Research Council of Canada grants permission to individuals to download or print single copies of articles published by the NRC Research Press: NRC Publications

The Ministry of Forests, Lands, Natural Resource Operations and Rural Development Publications Search

• Brockley, R.P. 2006. Effects of fertilization on the growth and foliar nutrition of immature Douglas-fir in the Interior Cedar–Hemlock zone of British Columbia: six-year results. B.C. Min. For. Range, Victoria, B.C. Res. Rep. 27.
• Brockley, R.P. 2001. Fertilization of lodgepole pine in western Canada. In: Proc. Enhanced For. Manag.: Fert. and Econ. Conf., Mar. 1–2, 2001, Edmonton, Alta. C. Bamsey (editor). Clear Lake Ltd., Edmonton, Alta., pp. 44–55.
• Brockley, R.P. 2000. Using foliar variables to predict the response of lodgepole pine to nitrogen and sulphur fertilization. Can. J. For. Res. 30:1389–1399.
• Brockley, R.P. 2000. Using foliar nutrient levels to predict lodgepole pine fertilization response. B.C. Min. For., Victoria, B.C. Exten. Note 44.