Answer: Unfortunately, your description has me somewhat stumped. I think it may be some kind of euphorbia, there are a number of different ones that grow wild in Kansas such as E. dentata pictured at the following url. Unfortunately the flowers are fading and fruit/seed is forming, but the foliage is somewhat like a poinsettia effect.
Here is another photo of an unnamed euphorbia, this one growing at the Lady Bird Johnson Wildflower Center in Texas, this one reminded me more of a poinsettia.
Since it is difficult to identify a plant based on description alone and we can't accept photos, you might want to check with a naturalist or wildflower specialist in your area and see if they can recognize your plant from either a sample or a photo, or check some reference books at the library. Your county extension might also be able to help.
Good luck with your project, I'm sorry I can't be more definite in my identification of your plant, it sounds very interesting!
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