Jun 26

Emerald Ash Borer

Posted on June 26, 2020 at 11:23 AM by Alicia Doran

EAB Tips for Front Range Residents

EAB was recently found in Arvada.  Jefferson County CSU Extension and Jeffco Invasive Species Management want homeowners to understand what they can do to prepare for Emerald Ash Borer (EAB), a non-native insect that attacks and kills ash trees. 

What You Can Do

Determine now if you have any ash trees. Identifying features of ash trees include compound leaves with 5 to 9 leaflets; leaflets, buds and branches growing directly opposite from one another; and diamond-shaped bark ridges on mature trees. More information about identifying ash trees can be found at the Colorado State Forest Service Emerald Ash Borer website.

If you have an ash tree, start planning. Decide if the overall health of the tree merits current or future treatment or if it would be best to remove and replace it with a different species. If you aren’t sure, contact a certified arborist. If pesticide treatment is the preferred option, the applicator must be licensed by the Colorado Department of Agriculture as a Commercial Pesticide Applicator.  A good resource for treatment options is Insecticide Options for Protecting Ash Trees from Emerald Ash Borer

Recognize signs of EAB infestation. Property owners with ash trees should be on the lookout for thinning of leaves in the upper tree canopy, 1/8-inch D-shaped holes on the bark and vertical bark splitting with winding S-shaped tunnels underneath. Report suspect trees by calling the Colorado Department of Agriculture at 1-888-248-5535 or filling out their EAB Report Form.

Be aware of EAB imposters. Other insects like lilac/ash borer, ash bark beetle and flat-headed apple tree borer may look like EAB or cause similar tree symptoms.

Help prevent spread of EAB.
Do not transport ash or any hardwood firewood, or any other ash wood products, to other locations. Firewood and wood products can harbor insect and disease pests.

For more information about ash tree identification, Emerald Ash Borer symptoms and control visit the CSU Extension https://extension.colostate.edu/topic-areas/insects/emerald-ash-borer-resources/  and Jeffco Invasive Species Management pages.


Arvada EAB 

Boulder EAB

Broomfield EAB

Lakewood EAB

Westminster EAB

Colorado Department of Agriculture

Colorado State Forest Service

Oct 23

Don't Invite Them In

Posted on October 23, 2019 at 1:04 PM by Alicia Doran

Fall is the time of year that mice and rats are looking for a place to be protected from the elements.  

Ways to Discourage Rodents
  • Keep food in sealable containers
  • Remove trash and garbage from inside your home
  • Remove vegetation and leaves from the perimeter of your home
  • Keep compost piles away from your home
  • Don’t leave pet food outside
  • Clean up any spilled birdseed from around bird feeders
  • Fill any cracks, openings or voids around your home 
Prevention is your best defense!

Aug 01

Douglas Fir Tussock Moth

Posted on August 1, 2019 at 8:45 AM by Alicia Doran

Doug Fir Tussock Moth - caterpillar

Douglas Fir Tussock Moth

Douglas fir tussock moth (DFTM) is a native insect whose populations are increasing in the southern portion of Jefferson County. In 2016 we saw over 24,000 acres defoliated near the Buffalo Creek area. According to the Colorado State Forest Service many of those trees will recover. Landowners in the affected area should monitor their properties and not move items infested with DFTM.

At this time of year DFTM is overwintering in the egg stage.
Landowners in the forested areas in southern Jeffco should be looking for egg masses now to determine if there is a possibility for large numbers of DFTM on their properties. Egg masses can be found on branches and the trunks of trees. The eggs are in a mass of very small pearl like eggs surrounded by grayish brown hairs. The eggs will hatch into very small caterpillars around late May, at the same time the trees will begin to bud. Landowners may decide to treat their trees if they find large numbers of egg-masses. The time to treat is in early spring when trees are growing new needles and the caterpillars first emerge Treatment is not effective after they get larger than about ¼ inch long.
?Treatment is not always necessary if the landowner can tolerate some impact to their trees. DFTM populations tend to subside within a few years. Trees will sometimes rebound but weakened trees may be attacked by bark beetles such as the Douglas-fir bark beetle or Ipps beetle. The Colorado State Forest Service has recently published a factsheet