I have a lot of wild plants that grow on my property. I have tried to find a good complete source of information to identify them all, but the major players always seem to be unknown. One particular plant is fairly common, the hogs eat it but the chickens ignore it, and I have mild allergies to it (sinus congestion and eye snot when it is pollinating). Any suggestions on how I can identify it? Here is a picture of the plant in bloom.