On Saturday, I spent time outside in the garden. Birds were singing, daffodils were blooming, and some of the flowering shrubs were showing the tips of baby-green leaves. I watched two carpenter bees flitting around a large rosemary, and I realized that June isn’t so far away, and the linden trees will bloom again. The previous owners planted three littleleaf lindens more than 40 years ago, and the trees have a good chance of living several hundred years if they escape severe disease, insect infestation, or environmental changes. In fact, longevity may be one of the reasons lindens were planted along streets and avenues in European, and later, in American cities. Lindens make reliable city trees because they tolerate poor or compacted soil and air pollution and can withstand occasional drought conditions, although leaf margins may scorch in prolonged heat. Newly planted trees should be watered during the first years. Littleleaf lindens (Tilia cordata), also called small-leaved lindens,...