Pin oaks are one of America's most popular trees for big cities and suburban lawns. Unlike other oaks, they have one strong leader from which all the other branches grow. Unfortunately, the branches tend to grow downward, so the lowest branches have to be removed higher than those of other trees to provide the same clearance. But pin oaks can grow 75 feet tall and last a long time. Below, they grace an outdoor cafe along Pennsylvania Avenue near the capitol building.