The low resolution images are from SPOT - they were collected between 2005 and 2010 (if you want you can download them from geobase.ca for free). The high resolution ones are from DigitalGlobe with collection dates from 2003-2010 according to a quick search on their site.
Jeff
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Algonquin Backcountry Recreationalists - Caring for Algonquin's Backcountry - abrweb.ca
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