Here comes Sam's murderers row of invasives. Callery pear is one of the newer ones on the list. It was introduced as the cultivated variety called Bradford pear. That tree was developed as a sterile form that would not spread. It has been around for decades, and worked very well. But we never leave well enough alone. Attempts to improve on this good thing led to varieties that were not sterile. Now Callery pears are rapidly spreading, and becoming a serious threat to native flora. Despite being a pear, the fruit are berries about 3/8 inch across. Birds spread them everywhere. Given any chance, they will take over your fields and roadsides. This image is from Ives Fen Preserve, where the tree and its relatives have now been eradicated. Reported so far from AL, AR, CT, DE, FL, GA, IL, IN, KY, MA, MD, MI, MS, NC, NJ, NY, OH, PA, SC, TN, TX, VA, and WV. Lenawee Co MI, 5/5/11.