Subject
Trees Diseases and pests
139
Forest insects
31
Shade trees Diseases and pests
14
Ornamental trees Diseases and pests
13
Trees Diseases and pests Control
11
Trees Diseases and pests Research
11
Shrubs Diseases and pests
10
Bark beetles
8
Forest health
8
Forest insects Environmental aspects
8
Trees Wounds and injuries
8
Aphids
7
Insect pests
7
Locust trees Diseases and pests
7
Plant mites
7
Anthracnose
6
Aphids Control
6
Forest management
5
Mountain pine beetle
5
Oyster-shell scale
5
Trees Diseases and pests Law and legislation
5
Trees, Care of
5
Bacterial diseases of plants
4
Beetles
4
Dwarf mistletoes Control
4
Forest fires
4
Forest nurseries Management
4
Spruce Diseases and pests
4
Sycamores Diseases and pests
4
Western spruce budworm
4
Wood borers
4
Birch Diseases and pests
3
Forest fires Law and legislation
3
Forest management Law and legislation
3
Insect pests Control
3
Introduced insects
3
Spruce bark beetles
3
Tree hazard evaluation
3
Wildfires Law and legislation
3
Wood-decaying fungi
3
Dwarf mistletoes
2
Emerald ash borer Biological control
2
Emerald ash borer Control
2
Entomology
2
Forest ecology
2
Forest fungi
2
Forest health Law and legislation
2
Forest insects Host plants
2
Forest plants Diseases and pests
2
Forest surveys
2
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