White willow is one of our common large willows on stream banks and in low areas generally. This Eurasian and other willows have long been used medicinally. After all, willows contain aspirin. Certainly you've heard that before. I have, and I believed it. Until right now! It turns out to be a myth. Aspirin is acetylsalicylic acid. Willows contain salicylic acid. Two different chemicals, the former created by chemists. Unlearn something new every day! White willow now grows in every state except AL, FL, HI, MS, OK, OR, SC, TX, UT, and in MB, NB, NS, ON, PE, QC, and SK. Lenawee Co MI, 5/3/11. Willow family, Salicaceae.