Glenfoyle Trial Shows Sustained Impact on Soil pH and Aluminium Levels

Introduction

High aluminum levels on Glenfoyle’s Blackstone Hill soils have been identified as being a key factor limiting pasture production (P Espie & R Dolby 2004). High aluminum levels occur when soil pH is low with the effect of restricting root development. Lifting the low pH levels will address the aluminum toxicity. 

Steep terrain (requiring aerial application) and proximity mean that transport and application costs are a significant issue for this type of hill country operation. Optimise is being trailed at relatively low application rates as a means of minimising the cost of addressing these key soil fertility issues. 

Treatments

The trial area is on the Zig-Zag site at an elevation of 790m. The trial consists of control plots and treatments as follows: 

• Control: Nil application 
  
• Treatment 1: Optimise pelletised ultra-fine lime at 250kg/ha 
  
• Treatment 2: Optimise pelletised ultra-fine lime at 500kg/ha 
  

Trial plots are replicated 4 times. Plots measure 5m x 2m ie 10m2 and are spaced 1m apart. 

24-Month Results

Soon after application soil test results show a significant and sustained increase in soil pH and reduction in aluminium levels.