Rich - my grass guru says the following:
I think you might have what you are calling bermuda grass mixed up with some other grass. Bermuda is a southern grass that to my knowledge will not survive in northern climates especially Colorado. But if you are sure it is bermuda then read the following. If you have a Fescue lawn then you probably hate common Bermuda grass. The grass that creeps into everything and can out right kill your Fescue lawn if it's not beaten back. In the past all we could do was dig it out or spray it with a non-selective herbicide and risk killing everything near it. Now we are lucky to have another option. There is a herbicide that will allow you to kill Bermuda grass in a fescue lawn. It is called Ornamec. The active ingredient is known as "Fluazifop". According to the label, to kill Bermudagrass in a Fescue lawn, use .5 ounces of Ornamec, 2 teaspoons of a non ionic surfactant to one gallon of water to treat 1000 square feet of lawn space. The first application should be made in the spring when the Bermuda grass is breaking dormancy and then again in Sept/Oct. when the Bermuda grass is preparing for dormancy. APPLICATIONS DURING THE HOT SEASONS SHOULD BE AVOIDED! Even when applied at the proper times, your fescue lawn may show some discoloration or stress but should recover within 10-14 days so do not worry if it looks sick. This is also labled for use over the top of many ornamental flowers, trees and shurbs, but refer to the label before applying to determine if it is registered for what you want to spray over. Wow, this can really make your life much better. You have to love modern science. Happy Spraying. This is a herbicide mostly used by commercial applicators but I have occasionally seen it in large garden centers. Here is a link to Ornamec online at Amazon.com: https://www.amazon.com/dp/B002HJ805Y/?tag=yardener-20. It does not affect fescue but will take out other favorable grass varieties.
Hope this helps. Best and Happy Yardening, Nancy