Controlling Weeds

The following "Fun Fact" was published August 22, 2005.

It is that time of year that we begin to control the most invasive and tenacious exotic plants in the park. The plants we will be treating this year include Canada thistle, leafy spurge, yellow and Dalmatian toadflax, field bindweed, and reed canarygrass. Patches of infestations, totaling approximately 20 acres, will be treated within the following locations: McGraw Ranch, Hondius Park, Endovalley, Headquarters area, Upper and Lower Beaver Meadows, Moraine Park, Glacier Creek Wetland and Hallowell Park. Vegetation Management Services has been contracted to begin applying herbicides on Monday, August 22.

Signs were posted the week of August 8 at all locations to be treated. Each sign includes the description of area to be treated, date, plant species, and herbicide being used. Safety recommendations include avoiding the treated area for 24 hours and for people who may be more sensitive, up to 48 hours. Herbicides are developed to target plants and not wildlife, so wildlife will be safe. A park employee will be escorting the contractor at all locations. He/she will be in charge of monitoring weather, making sure the correct plant species is targeted, and keeping visitors informed and within a safe distance.

In case you are wondering, last year's treatments were very successful especially on leafy spurge and the toadflaxes. Some of the sites did not have any exotics resprouting. Canada thistle was definitely set back, but it is our most troublesome weed and it has persisted to a lesser degree on some of our treated sites - so we are targeting it again.

Why are we using herbicides on the park? The decision involved a great deal of planning and discussion. Click here to learn a bit more about exotic species control and the factors that went into the decision to use herbicides. Also, please realize that they will be used in less than one hundredth of one percent of the park. In more than 99.99% of the park we will use means other than herbicides to manage weeds.

Last updated: March 31, 2012

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1000 US Hwy 36
Estes Park, CO 80517


(970) 586-1206
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