Measurement Bias: Yukon Forestry created a number of 10m by 10m plots within the Marshal Creek clear cut. Each plot we found was located within an areas in which slash from the clear cut had been burned. These plots recorded seedling growth rates and seedling success. The areas of the each slash burns represented less than 10% of the clear cut area.
ES classes set out parallel plots outside the slash burn areas and conducted seedling growth, health and survival measurements in the Yukon Forestry plots and in the adjacent plots to determine if the plots in the slash burn areas were different from the plots outside the burns. We found the growth rate (height) was 10 to 30 percent greater in the burn areas than in the adjacent plots (average 23% greater) and the survival rate 7 years after the planting 91% in the burns compared to 82% in the clear cut. The comparison showed that sampling in the burns produced growth and survival rates more favourable than those in the balance of the clear cut. ES classes concluded that there was intentional bias in the Forestry survey.
ES classes set out parallel plots outside the slash burn areas and conducted seedling growth, health and survival measurements in the Yukon Forestry plots and in the adjacent plots to determine if the plots in the slash burn areas were different from the plots outside the burns. We found the growth rate (height) was 10 to 30 percent greater in the burn areas than in the adjacent plots (average 23% greater) and the survival rate 7 years after the planting 91% in the burns compared to 82% in the clear cut. The comparison showed that sampling in the burns produced growth and survival rates more favourable than those in the balance of the clear cut. ES classes concluded that there was intentional bias in the Forestry survey.