The Mauna Loa silversword, Argyroxiphium kauense, or Kaʻū silversword, is a rare species of flowering plant in the aster family. It is endemic to the eastern and southern slopes of Mauna Loa on the island of Hawaiʻi. A. kauense occurs in mountainous shrublands, bogs, and open mesic forest. The species is managed by the National Park Service and Hawaiʻi State Department of Forestry and Wildlife. It is a federally listed endangered species of the United States. There are three known populations remaining, for a total of fewer than 1000 individuals. Description The Mauna Loa silversword is a primarily monocarpic, single-stemmed rosette shrub. The shrub consists of a spherical rosette of many silvery, dagger-shaped leaves. The silver reflection seen on the leaves is caused by the dense, felty leaf hairs that help to lower the UV absorption of the plant. The leaves are long and narrow, so when older leaves fail to fall off, they form a skirt around the stem of the silverword; the skirt then acts as protection from freezing. The trunks grow vertically, compared to smaller forms in the other species of the silversword. The Mauna Loa silversword can reach up to 1.8 meters (5.91 feet) in height and produce multiple flowering branches. Each rosette, or branch of the plant, can grow for 20 to 30 years and may reach 40–70 cm (15.7-31.5 inches) before flowering and producing dry fruit. Each fruit contains a single seed. As a monocarpic shrub, the silversword flowers only once, bears fruit, and then dies. The silversword is self-incompatible, meaning individuals are not capable of pollinating themselves. Life History The Mauna Loa silversword is a monoecious plant that has a lifespan of 10 to 30 years. At the end of its life, the plant grows a tall flowering stalk and blooms. The stalk can be up to 2.74 meters (9 feet) in height. It is in the sunflower family, so the plant’s stalk is made up of as many as 300 individual flowers, and each flower has 300 flower heads, for an average maximum of 90,000 offspring. Very few seeds successfully disperse, negatively impacting the already-low population growth rate. After a few weeks, the plant dies as a part of a monocarpic cycle. The blooms typically occur in August through September. Ecology Range The ancestor of A. kauense came to Hawai’i approximately 5 million years ago, where it underwent an adaptive radiation, leading