Judy Tajak found a mysterious plant in her garden and submitted a small sample for identification. The sample included a small woody stem with leaves attached. Mystery solved. This garden interloper appears to be the beginning of a small mulberry tree (genus Morus). So, is this plant a welcome guest or a threat? Although there are many species of mulberry, two common ones are red mulberry (Morus ruba) and white mulberry (Morus alba). The red mulberry is a native plant and never common. It’s rarely found away from the shade of mature moist woods. The white mulberry is a prolific fruit producer and aggressively colonizes open, sunny sites. It can be found in many urban settings, fence rows and abandoned fields. The white mulberry, a native of China, was first introduced to North America in the 1800s when colonists were attempting to produce silk. The white mulberry leaf is the main food source of the silk worm. The leaves of either tree are variable in shape: unlobed, 2-lobed, 3-lobed or multiple lobed. To complicate matters, leaf form can change as the tree matures. You can usually tell them apart by putting the edge of a leaf in your mouth. The red mulberry is fuzzy underneath while the underside of the white mulberry is smooth. Since definitive identification of type of mulberry tree is no easy matter, it may be better left to an arborist.