Free high resolution photo of wild blue flax flowers (Linum Lewisii). Blue flax, also known as Lewis flax, or prairie flax is a perennial plant native to North America. It was discovered by Meriwether Lewis on the Lewis and Clark expedition. It has tiny gray green grass like leaves and pale blue flowers with five petals. Great for xeriscapes and other low water applications as the plants are quite drought tolerant. Free picture for any use.