Mulberry Weed, Fatoua villosa, is an oddity – the only member of the Mulberry family (the Moraceae) in the Southeast that is a herbaceous plant rather than a shrub or a tree. Originally from East Asia, it is a relatively new arrival in North America (early 1960s),and is now spreading rapidly. The common name is derived from the plant’s close resemblance to small, seedling Mulberry trees.
Mulberry Weed is a summer annual with an upright plant form and large, alternate leaves. It is found primarily in disturbed areas, gardens and landscapes. Below is an example of the plant form.
The leaves are triangular or sometimes slightly heart-shaped, with toothed margins and prominent veins. The flowers are found in small clusters at the leaf axils, and have no petals. Leaves and flowers are pictured below.
Young plants can also closely resemble False Nettle (Boehmeria cylindrica), and both can be found in similar, shady habitats. The leaves of False Nettle, pictured below, are opposite, rather than alternate – the best distinguishing feature.
Mulberry Weed is a heavy seed producer, and the plants flower when only a few inches tall. The seeds mature quickly, and the plants are known to produce 2 to 5 generations in a single year. Thus the invasive potential is very high, and control is difficult once the plants are established.
For information on management and control, see this excellent bulletin from the NC State Extension Service: https://content.ces.ncsu.edu/mulberryweed-fatoua-villosa