Mulberry

Three species, three histories

There are three commonly cultivated mulberries:

• Black mulberry (Morus nigra) — Mediterranean origin, intensely flavored, the prized fresh-eating fruit
• White mulberry (Morus alba) — Chinese origin, milder flavor, primary food for silkworms
• Red mulberry (Morus rubra) — North American native, intermediate between the two

In English the unmodified word “mulberry” usually refers to the black, but in many regions (especially the US Midwest), it means white or red mulberry — leading to confusion.

The silk industry depends on it

White mulberry leaves are the only food silkworms will eat (commercially, anyway). The Chinese silk industry has been built on white mulberry cultivation for over 5,000 years — vast acreages of mulberry trees feed the silkworms whose cocoons are unwound to produce silk thread.

Today, China still leads global silk production, but India, Brazil, Uzbekistan, and Vietnam have significant mulberry-and-silkworm operations. Each kilogram of raw silk requires about 200 kg of mulberry leaves.

Berry bombing the neighborhood

In American suburbs and Midwestern cities, mature mulberry trees produce enormous quantities of fruit that mostly fall to the ground, staining sidewalks and cars purple. Because the trees are old, large, and free-standing, neighbors with mulberries often invite friends to harvest as much as they want.

The practice of “mulberry bombing” — shaking branches over a tarp to gather hundreds of fruits at once — is a Midwestern summer tradition.

Stains and dyes

Mulberry juice is one of the most aggressive natural fruit stains — purple-black, persistent, and difficult to remove from clothing. Pre-industrial dye-makers used mulberry as a fabric dye, though it fades over time.

The fruit’s high anthocyanin content (the same pigment that colors blueberries and bilberries) is why a single mulberry can stain a tablecloth permanently.