Forest Pests (Insects and Diseases)

Likely Forest Pests in Douglas County

Douglas County is home to several forest community types where forest pests (insects and diseases) may be found. The most common forest pests are listed below along with the Fact Sheets published by the Colorado State Forest Service (CSFS), the lead agency in the State of Colorado for forestry and forest management.  Naturally, forests in Colorado are host to endemic populations of forest pests. At times pest populations can reach epidemic levels and cause serious damage to forest communities as witnessed with the 2014-2015 Douglas-fir Tussock Moth outbreak. This outbreak resulted in a high rate of tree mortality. While some dead trees have been harvested, many remain in place. The most recent impact on many pines and other vegetation throughout Douglas County was the October cold of 2020 followed by significant temperature fluctuations. The best strategy for protection against forest insects and disease is to protect the forest resource through active management, creating a more resilient forest. 

Commons Insects and Diseases

Ponderosa Pine


Gambel Oak



Will someone come out and look at my trees?
Douglas County employs a professional forester through the wildfire mitigation program who is available to visit a property on a consulting basis to assess forest pests as well as wildfire hazards. You may contact Jill Welle via email [email protected] or phone at 720-733-6924. The CSFS also employs professional foresters who make site visits on a consulting basis, usually with an associated charge, contact them via email [email protected] or phone 303-660-9625.

Who is responsible for forest/vegetation management?
Property owners are responsible for the management of vegetation on their property.

Are there programs to assist landowners with forest management including the removal of dead trees?
There are potential cost assistance and technical service programs that can aid in management activities, including the removal of dead trees through the Colorado State Forest Service (CSFS) and possibly the Douglas County Conservation District depending on the funding program for qualified applicants. For more information visit and Douglas County also hosts a slash/mulch site, located in Castle Rock, for dead trees and other qualifying vegetative debris. Sometimes other local civic organizations assist community residents in some capacity.

Can authorities mandate the removal of dead trees?
Some communities may have Covenants, Controls, and Restrictions (CC&R’s) that mandate management actions on properties located within the respective community. Douglas County Government does not mandate the removal of dead trees on private property unless associated with an active building permit and accompanying wildfire hazard assessment as applicable.