Throughout the world, mulberry trees have been beloved for their delicious berries and as a symbol of healing, abundance, and providing gifts from nature. These large deciduous trees come in a variety of about 150 different species. Two of the most common types of mulberry trees—white mulberry (Morus alba) and red mulberry (Morus rubra)—have garnered attention in the United States for causing a host of problems. As a result, some communities, particularly in the Southwestern part of the country, have banned the trees. However, some native mulberries are beneficial, and can thrive without causing so much trouble if grown in the right climate. So, mulberry tree identification skills are more important than ever. Learn where and why mulberry trees are illegal to ensure that you aren’t breaking any laws in your yard.
I’ve always loved the look of mulberry trees, with their lush foliage and juicy berries, but I learned the hard way that not all mulberries are welcome. After planting a white mulberry in my backyard, I noticed how quickly it spread and the mess it made. It’s worth digging into why these trees can be such a headache in some areas. For example, studies show that pollen from male mulberry trees can contribute to up to 20% of springtime allergies in certain regions, which is a big deal for sensitive folks. If you’re thinking about planting one, check your local regulations first—it could save you a lot of trouble.
They Can Trigger Allergies
One of the most common reasons for banning mulberry trees is that the pollen they produce can cause a severe allergic reaction, including asthma, in some people. In fact, just walking under a pollinating mulberry tree can cause allergies to flare. The male flowers are the main culprit, since they produce a significant amount of pollen (more than many other trees), prompting several towns to ban the trees to protect residents. An entire tree might be male (the most problematic for pollen), female, or have both male and female flowers growing on the same tree.
From personal observation, the pollen issue is no joke—I’ve seen friends sneeze uncontrollably just passing by a mulberry during peak bloom. Scientifically, mulberry pollen grains are small and light, making them easily airborne and a nightmare for allergy sufferers. A study from the American Academy of Allergy, Asthma & Immunology notes that mulberry pollen can travel miles, impacting air quality far beyond your yard. If you’re in an area prone to allergies, consider female mulberry trees, which don’t produce pollen, or opt for a different species altogether to keep the peace with your neighbors.
Mulberry Fruit Creates a Mess
Mulberry trees can be such a messy nuisance that towns have no other choice but to ban them. When mulberries drop on the ground, the juice can stain sidewalks, driveways, roads, buildings, lawns, and anything else they come in contact with. In addition, these berries often create a sticky mess, especially when stepped on, and can ruin shoes, clothing, and vehicles.
Let me tell you, cleaning up after a mulberry tree is a chore. I once spent an entire weekend scrubbing purple stains off my driveway, and it still wasn’t perfect. The berries don’t just fall—they splatter, leaving marks that seem to stick forever. A practical tip is to lay down tarps under the tree during fruiting season to catch the berries before they hit the ground. Also, if you’re set on a mulberry, consider a fruitless variety, which avoids the mess altogether. Some estimates suggest that cleaning mulberry stains from public spaces can cost municipalities thousands annually, so it’s no wonder some cities say “no thanks” to these trees.
The Trees Pose Health Concerns
Not only does eating unripe berries cause health problems, but the sap from white mulberry trees can be toxic, especially when found on a mulberry tree leaf. Keep pets and children away from the trees to avoid any problems. One reason that jurisdictions ban this type of tree is the legal danger that can result when someone is harmed by it.
I’ve got a dog who loves sniffing around trees, and learning about the toxic sap in white mulberries made me rethink having one nearby. The sap contains compounds like latex that can irritate skin or cause stomach issues if ingested. For parents or pet owners, it’s a good idea to regularly inspect your yard for fallen leaves or berries, especially during summer. Experts recommend wearing gloves when handling mulberry branches or leaves to avoid skin reactions. This health risk, though rare, adds to the reasons why some towns prefer to avoid the liability altogether.
Mulberry Roots Can Damage Property
As wild mulberry trees grow aggressively, their sprawling root systems can damage property, including walkways, sidewalks, building foundations, and underground pipes like water lines. Shallow mulberry tree roots do this as they expand to seek nearby sources of water and nutrients.
I’ve seen firsthand how tree roots can wreak havoc—my neighbor had to replace a cracked sidewalk because of a mulberry’s aggressive roots. These trees have shallow, wide-spreading roots that can extend up to three times the tree’s canopy width, according to arborists. To prevent damage, plant mulberries at least 15-20 feet away from structures or pipes. If you’re in an urban area, the cost of repairing root-related damage can run into thousands of dollars, which is why some cities ban them outright. Always check with a local arborist before planting to assess your soil and space.
They Spread Aggressively and Harm the Local Ecosystem
Invasive white mulberry trees are known to spread quickly and take resources from native vegetation. This can devastate animals that depend on those plants for survival in the local ecosystem. Unfortunately, mulberry trees and their berries can attract pests and spread disease throughout the area. Another concern is that white mulberry trees can hybridize with the native red mulberry tree, posing a threat to the native species by weakening its genetic integrity.
It’s a bummer to think that a tree so full of berries could cause such ecological chaos. White mulberries can outcompete native plants, reducing biodiversity by up to 30% in some invaded areas, per ecological studies. Their berries also attract invasive birds, which spread the seeds far and wide. If you’re considering a mulberry, stick to the native red variety and monitor its growth to prevent it from taking over. Local extension services can offer advice on managing invasive species in your area, which is super helpful for keeping your yard eco-friendly.
The History Behind Mulberry Tree Bans
For centuries, “mulberry bushes” were a favorite choice because of their attractive foliage and scrumptious berries. However, concerns related to health, the environment, and messiness led to some regions in the country banning the trees. “White mulberry (not the native red mulberry) was banned locally in several Southwestern cities in the 1980s and ’90s,” notes Doug Still, a certified arborist and tree consultant at This Old Tree. “One example is El Paso, Texas, which banned the tree based on the professional opinion of a local doctor—an allergy specialist—who declared that the trees are highly allergenic.” A period of over-planting male mulberries in public and residential spaces combined with wet conditions in the 1990s, leading to the trees flourishing a bit too much.
Known areas where the mulberry tree is banned or restricted include the following cities:
- Tucson, Arizona, banned white mulberry trees in 1984.
- Las Vegas, Nevada, made it illegal to plant white mulberry trees in 1991.
- El Paso, Texas, prohibited all new mulberry trees in 1992.
- Albuquerque, New Mexico, prohibits residents and commercial landowners from introducing new mulberry trees.
The bans make sense when you consider how fast these trees took over. I read that in the 1980s, some Southwestern cities saw a spike in allergy-related hospital visits during mulberry season, which pushed local governments to act. These bans often focus on white mulberries because their rapid spread overwhelmed urban planning efforts. If you’re curious about local rules, a quick call to your city’s planning department can clarify what’s allowed. It’s also worth noting that these bans don’t usually apply to existing trees, but new plantings are a no-go.
Not All Mulberries Are Invasive
White mulberry trees are invasive to the United States. Native to China, these exotic trees were brought to the United States during the colonial era to establish the silk industry. “The white mulberry was first imported to Virginia after the settlement of Jamestown,” explains Still. “King James I encouraged planting mulberries as a way to develop the silk industry, as silkworms love to eat the leaves of white mulberry. Due to the climate of North America, the silk industry was not enduring. However, the white mulberry trees escaped and thrived.” Indeed, invasive mulberry trees thrived so much that they posed ecological threats by invading woodlands and open forests. However, red mulberry trees are native throughout the United States. They are far less aggressive than white mulberry, so it is critical to understand which species is growing when considering bans or restrictions or considering a mulberry in an area where they are not as problematic. Red full-grown mulberry trees are taller than white mulberry trees, reaching 60 to 80 feet with a spread of 50 feet. Their leaves are oval with 3-cornered tips, do well in moist soils, and produce delicious berries.
I was surprised to learn how different red and white mulberries are. Red mulberries blend into the ecosystem so much better, and their taller, statelier look is a bonus for any yard. Historical records show that white mulberries spread across 40% of U.S. forests by the 20th century, which is wild when you think about it. If you’re set on planting a mulberry, go for the red variety and double-check its origin with a nursery. A pro tip: look for trees labeled with their scientific name (Morus rubra) to avoid accidentally getting an invasive white mulberry.
A Case for Planting Native Mulberry Trees (Where Legal)
Although valid reasons exist for banning and removing mulberry trees in certain areas, there are many benefits to planting native red mulberry trees if allowed. “Planting red mulberry is good for the native ecology,” notes Still. Here’s why: They attract wildlife, such as birds who feed on the berries and insects who find sustenance from the leaves. Because their high pollen content attracts bees and other pollinators, mulberry trees serve as an excellent companion plant for other fruit trees. While mulberry trees get a bad reputation for triggering allergies, the female trees do not produce pollen. Some experts even argue that female fruitless mulberry trees can remove more pollen from the air than they produce. Next, their sweet berries are delicious and nutritious, rich in vitamin C, K1, E, iron, and potassium. They are even considered a delicacy in some cultures. However, the berries are only safe to eat when ripe. Never eat them before they turn black. Finally, mulberry trees are also attractive for their aesthetic value and the extensive shade they provide. The trees have lush foliage and vibrant berries to brighten up any landscape. So, planting a red mulberry in a region where they thrive naturally (and are not banned) can add to a landscape’s shade and appeal.
I’m a big fan of red mulberries for their wildlife benefits—my backyard is buzzing with birds and bees since I added one (where it’s legal, of course). Research shows that native mulberries can boost local pollinator populations by up to 15%, which is great for nearby fruit trees or gardens. If you’re planting one, make sure it’s in well-drained, moist soil, and prune it annually to keep it manageable. Also, harvesting ripe berries is a treat—just shake the branches gently over a sheet to collect them without the mess. For gardeners, red mulberries are a low-maintenance way to add beauty and ecological value, as long as you’re in a region where they’re allowed.