Marion Heinz discovered monarch roosts near Henderson, Minnesota on August 25, 2015:

"While walking at a local nature center this morning I saw numerous small clusters of monarchs roosting. There were 15+ clusters with 15-30 monarchs per cluster. I walked about a one-mile stretch with the morning sun on my right and the tree line on my left, spotting clusters in the sunny areas all along the way. First, small groups of flying monarch caught my eye. Then I spotted others in the trees and many resting in the wet grass. Seeing over 200 roosting monarchs was a delightful sight on such a beautiful morning."