Emerald Ash Borer

Emerald ash borers (Agrilus planipennis) are non-native, wood-boring beetles that feed on ash trees (Fraxins sp). EAB has rapidly spread throughout North America since first being detected in 2002, resulting in the loss of millions of trees. EAB has not yet been found in Alberta, but predictions show it could arrive in Calgary in 2024.

While adult beetles only feed on foliage, causing minimal damage, the larvae burrow beneath the tree's bark and stop the flow of water and nutrients up the tree, leading to the tree's death.

In Calgary, we have over 70,000 public ash trees, with many more on private land. This means EAB poses a severe threat to our urban canopy.

While EAB has not yet been found in Calgary, we are monitoring it proactively, as early detection is critical in helping us slow its spread and prolong the life of our ash trees.

In spring 2024, we are setting up 200 traps throughout Calgary to monitor for EAB. We use green prism traps placed in ash trees across the city from late May to early September. The traps, made of corrugated green plastic, are coated with sticky glue on the outside and baited with pheromone lures to attract insects.

If you find one of the traps, please:

• Don't touch the outside of the trap, as it is coated with sticky glue that may cause skin irritation.
• Do not touch the lures inside the trap; they will be placed back into the tree for the remainder of the monitoring season.
• Contact 311 so we can try to locate and replace the trap.

In addition to using the traps for EAB detection, we also collaborate with surrounding municipalities and provincial and federal partners to monitor the spread of EAB across Canada and the United States.

EAB can spread up to 20km per year under its power but can spread much faster with unintentional human help. The transport of infested ash products, such as firewood, is the primary method of human-assisted spread. The number one thing to stop the spread of EAB is to ‘Burn It Where You Buy It’ and not transport firewood from place to place.

Within the first few years of an infestation, trees still appear healthy. Once EAB populations have grown, signs of infestation on a tree include:

• D-shaped exit holes in the tree bark
• Thinning or yellowing of the tree's crown
• S-shaped markings left from larval feeding under the tree bark
• Epicormic shoots (also known as water sprouts or suckers) growing from the trunk of the tree
• Woodpecker damage, such as bark flaking or the presence of woodpeckers in the winter.

Adult EAB beetles are metallic green, about 8.5 to 14mm long, and 3 mm wide.

If you see a tree that shows signs of EAB infestation or spot a beetle that you suspect might be EAB, please contact 311.