Two sure signs of spring in the Chicago area are end-of-year band concerts at schools, and plants beginning to grow. This week we revisit a couple of stories from the archives on that theme. First, tenacious weeds like buckthorn, milkweed and goldenrod grow everywhere in Chicago from railroad tracks to sidewalk cracks. We find out how they survive city life. Plus reporter Monica Eng gets an answer to the question: why do so many kids learn to play the recorder in school?