Boreal mixedwood forests have been commercially logged for conifers, transected by roads and seismic cutlines, and regionally fragmented by agricultural practices.

Most recently, Alberta's public mixedwood forests have been allocated for harvest of trembling aspen for pulp, paper, and oriented strand board products. With relevance to commercial forestry, this report describes the structure and biodiversity of aspen-dominated mixedwood forests of fire origin. The boreal mixedwood forest in Canada extends from southwestern Manitoba, through the central and northern parts of the Prairie Provinces, and into northeastern British Columbia.

A scientist is studying the relationship between x= diameter at breast height (DBH) (in centimeters) of aspen mixedwood forest in Alberta and y= canopy height (in meters). The data are as follows.

x

5.1

7.9

7.1

7.4

15.8

16.4

15.9

13.9

37.0

29.8

45.0

37.0

y

7.1

11.0

9.5

9.2

18.7

19.9

18.8

15.1

25.5

22.0

23.4

26.7

a) Find a 95% confidence interval for the slope of the line.

b) Estimate the change in canopy height for a l-unit change in diameter at breast height. Use a 99% confidence interval. Compare this interval with the interval in part o.