Forest health aerial survey maps

Forest health conditions are dynamic. Therefore, forested areas in Alberta are monitored annually for insect, disease, and weather-related disturbances. Since 1998, the province has carried out annual aerial overview surveys (AOS). These surveys record the location and severity of disturbances caused by forest health damage agents (FHDA) on forested lands. AOS are foundational to forest health monitoring in Alberta. They are a very cost-effective method for detecting and monitoring disturbances to Alberta’s forested areas, providing valuable information on forest pest conditions.

Traditionally, AOS mapping included only large-scale, FHDA-caused disturbances (for example, defoliators and bark beetles). However, with a changing climate and more extreme weather events, more attention is being paid to mapping other potential issues. These could include introductions of new FHDA and/or range expansions of current ones within Alberta; and more frequent abiotic damage such as hail, large wind events, and drought.  Climate change can also affect the frequency and severity of abiotic damaging agents, such as hail or large wind events. Information from aerial overview surveys helps understand the impacts of forest pests and other disturbances, and to predict how climate change might affect forest disturbances in the future.

Here are maps and data pertaining to AOS in Alberta:

Forest health aerial survey map data

Forest Health data now available on the GeoDiscover website

Forest pest status update – aerial overview surveys 2020 – 2023

Table 1. Highlights (in hectares) from 2020 to 2022 aerial overview surveys.

1 Excludes mortality caused by mountain pine beetle, 2 Co-occurred with large aspen tortrix and damage by both could not be separated. 3 Present but not recorded.
Damage Agent 2020 2021 2022
Bark beetles      
Douglas-fir beetle 2,220 2,394 888
Easternlarch beetle 2,519 5,314 3,777
Spruce beetle 2,853 2,098 182
Total bark beetles1 7,592 9,806 4,847
Aspen defoliator complex 366,052 965,697 134,322
Aspen serpentine leafminer 29,275 206,178 215,675
Aspen twoleaf tier 157,816 33,768 34,860
Bruce spanworm 277,391 --2 --
Forest tent caterpillar 77,518 86 --
Large aspen tortrix 96,839 116,613 109,407
Satin moth 13,773 17,059 2,553
Spruce budworm 65,720 100,550 68,069
Multiple agents/Unknown/Other 301,093 17,756 2,863
Willow leafminer 4,280 8,023 10,558
Total Defoliators 1,389,757 1,466,660 578,307
Diseases and parasites      
Armillaria and other root diseases 7,107 13,503 6,998
Dwarf mistletoe 42,493 32,904 37,734
Pine needle cast 215,386 95,505 94,716
Spruce needle rust 873 4,533 3,297
White pine blister rust 9,696 --3 12,607
Total diseases 275,555 146,445 155,352
Dieback (multiple agents/unknown) 102,337 75,527 75,752
Flooding 11,463 41,353 18,707
Foliar damage (including scorch) 9,029 2,552 12,854
Hail 2,131 7,824 10,015
Mortality (multiple agents/unknown) 676,070 614,147 298,875
Windthrow/blowdown 526,990 8,544 3,498
Total Other 808,594 749,947 419,657
Total damage recorded 2,481,498 2,372,858 1,158,163


Annual report

The Alberta government publishes an annual snapshot of programs related to the management of forest health and adaptation in the province's forests.

See: Annual Reports: Forest Health and Adaptation in Alberta (2013–2019)

The annual report includes: 

  • Details on work to detect, monitor, assess and manage insects, diseases, and other disturbances that damage the health of our forests. 
  • Overviews of programs in place to address notable forest disturbance in the province, and summaries of research underway to produce well adapted trees. 
  • Summaries of seed research, seed collection, plant propagation and genetic trials carried out by the Alberta Tree Improvement and Seed Centre (ATISC).

Bugs and Diseases Newsletter

The Bugs and Diseases newsletter informs forest industry, other forestry-related personnel, and the public about current forest health issues. It is a fun and informative look at forest health in Alberta.

The newsletter is published 2 times a year in April and October.


Connect with Alberta Forest Health and Adaptation: [email protected]

Talk to Alberta Forestry staff in your area: Forestry Area Office Contacts

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