This agave (in my back field) is about 7-8' tall. ***The misnamed century plant typically lives only 10 to 30 years. It has a spreading rosette (about 4 m/13 ft wide) of gray-green leaves up to 2 m (6.6 ft) long, each with a spiny margin and a heavy spike at the tip that can pierce to the bone. When it flowers, the spike with a cyme of big yellow flowers may reach up to 8 m (26 ft) in height.
*** from wikipedia AKA american aloe, century plant and maguey