July 20, 2013
1 - Many gardeners do not recognize mulberry seedlings when they come up in their garden because mulberry seedlings produce a variety of leaf shapes.
Yard and Garden July 20, 2013
Can you help me identify these plants? The first plant is about 2.5 feet tall and came up as a volunteer a couple of years ago. Its leaves have many lobes. The second plant is 14 inches tall; it is actually two separate plants. I am not sure if it is a tree or shrub.
In both cases you appear to have mulberry seedlings. The leaves look distinctly different, but mulberry trees are known to have polymorphic leaves even on the same plant. That means the leaves have different forms. This is especially true of mulberry seedlings. In the case of the first plant, the leaves have seven lobes and the lobes have lobes. They look somewhat like the leaves of some varieties of figs to which they are related. Like figs, they have white latex that drips freely from the point where leaves are broken from the twigs. The white latex will help confirm the identification of the plants as mulberry trees.
The second sample has heart-shaped leaves that are more characteristic of mature trees, though some mature trees may have variation in the shape of their leaves. Two lobes in a mitten-shaped leaf are common. Such leaves have a large lobe like the fingers portion of a mitten and then a smaller, thumb-like, lobe. Fruitless, white mulberry trees that are commonly grown as an ornamental in New Mexico often exhibit the heart-shaped and mitten-shaped leaves.
Since these are small, seedling trees, they are not from the fruitless white mulberry, but are probably from red mulberry trees (Morus rubra) that also grow in New Mexico. Birds often spread the seeds as they eat the tasty fruit. The extreme variation in lobes exhibited in the photographs you sent are typical of the seedlings of red mulberry. The leaves of seedling trees may look nothing like the mature trees, or may be identical to the leaves on mature trees.
Your decision to keep or dispose of these trees should be based on the knowledge of several factors. These trees may become fairly large so they should not be allowed to grow near walls and other structures. These trees will produce fruit that can stain sidewalks and your carpets if carried indoors on the soles of shoes. The fruit is considered to have a pleasant flavor by many people and can be used in jams, pastries, and other treats. Mulberry pollen is also a major cause of allergies in the spring. Keep both the positive and negative characteristics in mind as you make your decisions regarding the mulberry seedlings.
For more gardening information, visit the NMSU Extension publications Web site at http://aces.nmsu.edu/pubs/_h, or to read past articles of Yard and Garden go to http://aces.nmsu.edu/pubs/periodicals.html
Send your gardening questions to:
Yard and Garden, Attn: Dr. Curtis Smith
NMSU Agricultural Science Center
1036 Miller Rd.
SW, Los Lunas, NM 87031.
Curtis W. Smith, Ph.D., is an Extension Horticulture Specialist emeritus with New Mexico State University's Cooperative Extension Service. NMSU and the U.S. Department of Agriculture cooperating.