Horsetail:

Equisetum, commonly known as Horsetail is a slender potentially two feet tall plant with joint stems with whorls of branches. At their tips, a small spore-producing cone arises from separate stems. They can be found in moist woodlands, roadsides, swaps, mountains, and gardens. This plant is very old and can grow a new plant from any part of the old stem making this is very difficult plant to get rid of if unwanted.

Kavanagh, James, and Raymond Leung. The Nature of Alaska: An Introduction to Familiar Plants, Animals & Outstanding Natural Attractions. Phoenix, AZ: Waterford, 2005. Print.

OSU, n.d. Web. 26 Sept. 2014. <http://oregonstate.edu/dept/nursery-weeds/weedspeciespage/horsetail/early_habit_750.jpg>.