Swanson Larch Tree Arabinogalactan (AG) is a glyconutrient derived from the sap of the northern Minnesota larch tree. This "miracle sugar" has shown an amazing ability to maintain and balance the immune system, helping individuals to achieve optimal health! Larch Arabinogalactan is purported to be twice as beneficial to the immune system as echinacea, and it continues to be the subject of research on methods to boost immune system strength. AG has been found to stimulate production of monocytes, which are among the body's first defense mechanisms, and enhance the growth of NK (natural killer) cell activity.