[Wikipedia] Ecology, Human Use: It was first collected for science by scientist and explorer Meriwether Lewis in 1806 during the Lewis and Clark Expedition, and so was named after him. Philadelphus lewisii is able to spread vegetatively and from seed. It forms seedbanks in the top 2 inches (5.1 cm) of soil. Fire ecology The shrub is native to relatively arid regions of the American West which experience frequent wildfires, and is therefore quite well adapted to fire. Although mock-orange is typically completely top-killed by fires, it will enthusiastically resprout from rhizomes and root crowns afterward. A 1971 study found that in the next growing season after a fire, mock-orange had already regrown to 50% of its previous diameter and height, and that those plants had an average of 28.9 to 38.0 sprouts per plant postfire compared to just 0.6 to 1.5 before. Human use Ethnobotany Native American tribes used P. lewisii for numerous purposes. The hard wood was useful for making hunting and fishing tools, snowshoes, pipes, combs, cradles, netting shuttles, and furniture. The leaves and bark, which contain saponins, were mixed in water for use as a mild soap. The flowers were used in preparing perfumes and teas. (link added by Mary Ann Machi)