Cirsium Douglasii Lambert M Surhone, Mariam T Tennoe, Susan F Henssonow Betascript Publishing, Mar 2, 2011 - 76 pages Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Cirsium douglasii is a species of thistle known by the common names Douglas' thistle and California swamp thistle. It is native to California and adjacent parts of Oregon and Nevada, where it grows in wet places in a number of types of habitat. This native thistle is a biennial or perennial herb growing up to 2.5 meters tall, with a branching woolly stem. The longest leaves, located about the base of the plant, are up to a meter long. They are sometimes lobed or toothed and are borne on a spiny petiole. The inflorescence is a cluster of several flower heads surrounded by small leaves. Each flower head is up to 3 centimeters long and lined with purple-tipped spiny phyllaries. The head contains purple or white flowers. The fruit is a dark-colored achene a few millimeters long with a pappus which may reach 2 centimeters in length. |