Aspen currently unconcerned with presence of aphids

The city of Aspen has identified an increase in small, sap-sucking insects this summer compared to previous years, but the level of concern is still low. 

Aphids, as referred to by the scientific community, primarily impact deciduous trees — those that shed their leaves annually like aspens. While aphid presence can increase stress on trees by feeding off their sap, Parks and Open Spaces’ Natural Resource Manager Shelly Grail Braudis confirmed numbers are still not high enough to cause any high stress or impact.

“We would know if we started to see leaves dropping and trees looking very stressed, and we’re not seeing that right now,” Braudis said. “We’re really not too stressed about it.”

Aphids have been identified in Aspen previously, occurring in what Braudis called “cyclical” patterns.Roughly three or four years will pass between summer seasons where their presence is noticeable. 

An increase in aphid presence is primarily noted by the sticky residue they leave behind on leaves and other objects, like cars or outdoor furniture, known as “honeydew.” While honeydew might be an inconvenience, it’s possible to clean it using water and a mild detergent. 

Aside from trees, aphids aren’t impacting any other part of the Aspen ecology. As the season starts to change, they’ll disappear as they have in the past.

“Once the season ends, that’s when we’ll see them leave,” Braudis said, since the leaves they occupy will fall off the trees. “They’re just here (now) and providing an additional shine to Aspen.”

Residents can contact the city with any questions or concerns about tree health by emailing shelly.braudis@aspen.gov.