Monitoring the drying of residue bundles during storage in the forest and at a terminal in Ireland

Bundles derived from green and brown forest residues from Sitka spruce (Picea sitchensis) were stacked in the forest and at a terminal in a range of treatments between March and August 2010. Pre-storage mean moisture content was 50.8% and 54.0% for green and brown bundles respectively. After 18 to 21 weeks storage all treatments lost weight and dried significantly. In-forest green bundle stack moisture content ranged from 28.3% and 39.2% while brown ranged from 39.5% to 47.5%. Post-storage moisture contents at the terminal ranged from 23.3-25.1% and 28.8-32.4% for green and brown bundles. Covering stack tops had a significant effect on green bundle drying in the forest but not on brown bundle drying inforest or any bundles stacked at the terminal. Further, stacking bundles in a double rather than single row did not affect drying. Finally, there was no significant difference in observed drying rate between bundles stacked in an exposed compared with a sheltered forest location.