Mulberry Trees, No Thanks


Setting aside the associated nursery rhyme and its several contradictions, one of the first trees most children learn is mulberry. But that has not always been the case. While there is a native mulberry in the Midwest (red mulberry, Morus rubra), few people know it -- an uncommon resident of natural areas. The vast majority of mulberry trees we encounter are related to an Asian import (white mulberry, M. alba) first introduced into Georgia in the 1730's as part of an attempt to create a silk industry in the states. While the idea of growing mulberry leaves to feed silkworms failed (i.e., went away) this exotic tree did not. It naturalized and hybridized and has become one of our worst weedy plants. A major reason for the problem is the tremendous amount of fruit and seeds it produces, and the majority of the seeds seem to germinate. The sweet edible "mulberries" were one of my boyhood favorites. Unlike the name suggests, the fruit is not a berry -- rather a multiple fruit consisting of drupelets. The green peduncle (fruit stalk) also is edible. Wildlife covet the fruit which they help spread. And, although the delicate juicy bounty is delicious, it creates a mess. The fallen fruit stains your hands and hard surfaces purple and are the bane of anyone who hangs items to dry in early summer. NOTE: while there are white mulberry cultivars with fruit that mature white, most of the wild plants have fruit that start out white but, when ripe, are nearly black with a hint of red. There is also a great deal of variation in fruit size, especially the length. In fact, our plants are mostly if not entirely red x white hybrids.

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Mulberry is coarse looking, fast-growing, typically with low-branching, and is easy to identify. The bark of young specimens is orange-brown and nearly smooth, but the trunks of older specimens are narrowly furrowed and browner, sometimes with horizontal rippling. It also commonly produces deformities (witches' brooms) at the end of branches. The hand-sized simple leaves are polymorphic, ranging from unlobed to variously mitten shaped. They are serrate, have prominent light-colored veins, and exude a milky latex when detached. White mulberry leaves differ from the native species in being somewhat hairy below. The young roots of mulberry trees are yellow-orange and often possess dark tiger-like stripes. I already described the appealing and ofttimes despised fruit. Mulberry is found on practically every property, especially in fencerows, waste areas, and as grow throughs, deposited there by perching birds. The nasty Asian bush honeysuckle is a common associate. (See my book {Chapter 96} and May 2020 Rant).


As I have noted in past posts, when attempting to eradicate unwanted woodies, one usually must deal with the roots. Lopping off above ground is often merely a pruning action. This is especially true with mulberry. The plant normally will produce new branches. Mulberry wood is hard, and your hands and gloves will become sticky from handling freshly cut pieces due to the aforementioned latex.


This is NOT a desirable tree. The only nice specimen I have witnessed was in the backyard of my wife's childhood residence in N central Indianapolis. An arborist was annually employed to pollard the specimen into a thick-trunked climber. A vigorous species, mulberry responds well to pollarding. Since its flowers are produced on old wood, pollarding all but eliminates fruit production. However, do not let this potentially enticing example mislead you. My advice: attempt to get rid of ALL the mulberry specimens (large and small) on your property. Should you have a hankering for some of the fruit come mid-June, you will find there is no shortage elsewhere.


Finally, white mulberry has an interesting biological attribute. The pollen is released from its flowers (catkins) with great force -- at over half the speed of sound. This is reported to be the fastest movement in the plant world.

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