Is this plant a"horsetail"? And what is the scientific name of the plant?
All my adult life, I've referred to the plant, in the three images, as a "horsetail", but all of the WWW images show a green plant in very moist conditions, and none of the WWW photos are similar to what I 'captured'. This plant flourishes in an arid landscape, and in thin sandy soil. It grow up to five-feet tall, and most commonly, as a single 'stalk'. The submitted images were captured at Cherry Creek State Park, on Friday, 27Oct2017.. I am most interested in its scientific name.
Arapahoe County Colorado
This plant (and many others like it in the background) is Common Mullein (Verbascum thapsus). A very common weed in Arapahoe County, it is on the Colorado Noxious Weed List C https://www.colorado.gov/pacific/agconservation/noxious-weed-species
Field Horsetail is Equisetum arvense, a primitive plant that thrives in moist soils.
Thank you, very much! I have stopped referring to the 'mullein' plant as a "horsetail", and I now use its scientific name V. thapsus. And yes, the invasive weed, and other invasive 'weeds', is taking over some areas at Cherry Creek State Park. A real problem for the State park, from my viewpoint.