365 Urban Species. #234: Cucumbertree

Photos by cottonmanifesto. Location: Brookline Ave., Boston.

Urban species #234: Cucumbertree Magnolia acuminata

This tree was a mystery to us until cottonmanifesto asked for some help identifying it from her blog readers. It's a large tree, but it's in a bushy row of trees between the street and our nearby city park. Its leaves are huge and glossy, but otherwise not distinctive, and in late summer, it bears bizarre-looking fruit. A knowledgeable friend in Pennsylvania recognized it as a cucumbertree, native to the hillier parts of eastern North America, including the western half of Pennsylvania. It is not native to Massachusetts, but in Boston that is true of a majority of our tree species. It is, in fact, a magnolia; the most cold-loving species of a group of trees more well-known in the southern states.

The magnolia family is an ancient group of flowering plants which evolved before "advanced" insects such as bees and butterflies. Instead magnolias rely on beetles to pollinate them, and their flowers are sturdy, fleshy structures that can withstand the attention of heavier insects. While other magnolias are known for their showy flowers, the cucumbertree's flowers are yellow and green, and, though large, blend in with its oversized foliage. The cucumbertree is named for its long pinkish fruit, which, when young, is fed upon by blackbirds. The seeds of the tree are eaten by other birds and mammals. The tree was undoubtedly chosen for planting in the park for its rapid growth, its value as a shade tree, and for its exotic character. Its position at the edge of the road allows it the full sun that it craves; also, fortunately, cucumbertrees can tolerate the acid, sandy soil that characterizes an urban roadside.