If you haven’t seen these purple triangular tubes swaying from trees on the roadside yet, you will. Curious, I looked into it, and they turn out to be insect traps. The emerald ash borer—a non-native species—threatens to lay waste to our ash trees, having killed some thirty million thus far, and agriculture departments throughout the country are trying to figure out what sort of a problem they’re facing. These traps don’t necessarily mean that the borer is a problem, just that officials are investigating. When you see them, just leave them alone and hope for the best.
For more information, here’s a Kansas newspaper article on the topic.