Upper Ottawa River area, MS of two men walking along forest trail. MS of clearing in forest where weather enclosure is set up. LAS of cups on top of anemometer spinning in wind. TILT DOWN to animometer box and rangers checking same. MCS and CS of rangers checking maximum and minimum thermometers and making notes in logbook. MCS of men checking rain gauge funnel and graduate. MCSs of smoke generator in operation on forest cleaning. Numerous shots of light aircraft "Otter" flying over Northern Ontario forests and lakes.