The response of Sitka spruce to sulphate of ammonia and ground rock phosphate on peat.

  • E.P. Farrell Department of Agricultural Chemistry and Soil Science, University College, Dublin.
  • D.M. McAleese Department of Agricultural Chemistry and Soil Science, University College, Dublin.
Keywords: Fertilisers, ammonium sulphate, ground rock phosphate, factorial experiments, foliar analysis Sitka spruce, peat, vegetation, height increment, leader breakage, silviculture, Picea sitchensis, peatlands.

Abstract

Major site amelioration is needed to overcome the serious physical and nutritional problems encountered by tree crops on blanket bog. A 4X3 N P factorial experiment was established at Glenamoy in 1967 to examine the response of P'62 Sitka spruce to fertilizers on peat. The trees had received 85 g ground rock phosphate (G.N.A.P.) per plant at planting. G.N.A.P. was applied at levels of 0, 375, 750 and 1,500 kg/ha and sulphate of ammonia (S/A) at 0, 625 and 1,250 kg/ha. The fertilizers were applied in 1967. The 625 kg/ha S/A application was repeated in 1969. Height growth results from the first four years of the experiment and foliar analysis from the first three years are presented here. The results confirm the need for a second application of phosphate on oligotrophic peat. Significant height growth responses were obtained, but no additional response was observed above the lowest level of G.N.A.P. application. A significant height growth response to S/A was also recorded. Serious leader breakage, which occurred in 1969, was found to be related to total tree height. Foliar N concentrations were significantly increased by both fertilizers. The results indicate that tree growth will be seriously limited below 1.0 % N. Concentrations of P were significantly reduced by S/ A application. This was a dilution effect due to an increase in needle weight. Both fertilizers significantly reduced foliar K concentrations.
Published
1972-11-01
How to Cite
Farrell, E., & McAleese, D. (1972). The response of Sitka spruce to sulphate of ammonia and ground rock phosphate on peat. Irish Forestry. Retrieved from https://journal.societyofirishforesters.ie/index.php/forestry/article/view/9221
Section
Articles