Subject
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Wildlife
2
Woody plants
2
Yields
2
Abandoned Mines
1
Acid mine drainage
1
Acid pollution of rivers, lakes, etc
1
Acid rain
1
Aerial photography in botany
1
Aerial spraying and dusting in forestry
1
Aeronautics
1
Age
1
Air pollution
1
Alluvium
1
Aluminum ores
1
Analytical geochemistry
1
Animal contraception
1
Animal populations
1
Ants
1
Aquatic biology
1
Arsenates
1
Arthropod populations
1
Aspen
1
Asphalts
1
Atlantic Provinces
1
Bacillus thuringiensis
1
Bats
1
Baxter State Park (Me.)
1
Beavers
1
Bees
1
Beneficial insects
1
Beneficiation
1
Bioaccumulation
1
Biodiversity conservation
1
Biography
1
Biological diversity
1
Biometry
1
Biostratigraphy
1
Biotic indices
1
Birches
1
Bird pests
1
Bismuth
1
Bitumens
1
Black bear
1
Blueberries
1
Borers (Insects)
1
Butterflies
1
Camp sites, facilities, etc
1
Canada
1
Canker-worms
1
Celestite
1
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