Larch arabinogalactan is a polysaccharide powder derived from the wood of the larch tree (Larix species) and comprised of approximately 98 percent arabinogalactan. Arabinogalactans are found in a variety of plants but are more abundant in the Larix genus, primarily Larix occidentalis (Western Larch). The Western Larch is unique among pines in that it loses its needles in the fall. Western Larch is also known as Mountain Larch or Western Tamarack and is native to the Pacific and Inland Northwest United States as well as parts of British Columbia, Canada. Larch arabinogalactan is approved by the U.S. Food and Drug Administration (FDA) as a source of dietary fiber, but also has potential therapeutic benefits as an immune stimulating agent and cancer protocol adjunct.