Field horsetail (Equisetum arvense) is in the Equisetaceae family which was comprised by over 30 species some 230 million years ago. The horsetail family was the dominant plant group in that time period. Currently, two surviving species from the family which many of us today call weeds are E. arvense and E. hyemale, or scouring rush. Therefore, these ‘weeds’ have been around a long time so it’s obvious they have a tremendous ability to adapt to their environment. Field horsetail is a perennial weed that vegetatively re-propagates by spreading rhizomes. It is additionally unique because it is a non-flowering plant so it does not reproduce my seed, but rather, it reproduces by spores. The reproduction by spores occurs early in the spring when a single, fertile brownish stalk emerges and produces a ‘cone-like’ structure which releases the spores at the top of the main stalk. This early growth is followed by a single, sterile green stalk and then branched, green plants as shown in Figure 1.