A dramatic transformation in the alfalfa seed industry began after WWII when researchers realized that alfalfa flowers require cross-pollination. In the 1950’s it was discovered that the native alkali bee, Nomia melanderi, and the inadvertently introduced alfalfa leafcutting bee, Megachile rotundata, are better pollinators of alfalfa flowers than are honey bees. Growers in the Northwest began to specialize in alfalfa seed production as opposed to taking seed as a by-product of forage production.