Spiky, round objects scattered across lawns and sidewalks often spark curiosity about their origin. These distinctive “gumballs” appear consistently each year, leading many to wonder which tree produces them. Understanding the specific tree and the nature of these objects clarifies their presence in many landscapes.
Identifying the “Gumball” Tree
The tree renowned for dropping these spiky spheres is the sweetgum, scientifically known as Liquidambar styraciflua. This deciduous tree is native to warm temperate regions of eastern North America, extending into Mexico and Central America. It commonly grows 60 to 75 feet tall, though wild specimens can reach heights of 120 to 160 feet.
Identifying a sweetgum tree involves recognizing several key features. Its leaves are distinctly star-shaped, typically having five to seven sharply pointed lobes with serrated edges. In summer, these leaves are a glossy green, transitioning to vibrant shades of yellow, purple, and red in the autumn. The bark of mature sweetgum trees is grey-brown, characterized by deeply furrowed, scaly ridges. Younger twigs may develop corky, wing-like projections.
What Are Sweetgum Balls?
The “gumballs” produced by the sweetgum tree are actually its fruit, specifically an aggregate fruit or “syncarp.” These are hard, dry, and spherical, typically measuring between 1 and 1.5 inches in diameter. Each fruit is composed of numerous individual capsules, with each capsule containing one to two small, winged seeds. The spiky exterior of the ball comes from the pointed projections of these fused capsules.
Sweetgum trees produce small, inconspicuous yellow-green flowers in the spring as their leaves emerge. Following pollination, the female flowers develop into green, spiky clusters, which gradually mature and turn brown throughout the growing season. The mature fruit balls drop from the tree starting in late fall and continue through winter. Once on the ground, the capsules within the ball open to release their winged seeds, which are then dispersed by wind or consumed by birds and small mammals.
Why Sweetgum Balls Are a Nuisance
The volume and physical characteristics of sweetgum balls make them a nuisance in residential and public areas. These hard, spiky spheres can create a tripping hazard on lawns, sidewalks, and driveways, potentially causing falls. Their rigid structure makes them difficult to manage with standard yard equipment.
Attempting to rake them is ineffective, as they resist collection due to their shape and ability to interlock. Running a lawn mower over them can damage the mower or cause the balls to be propelled at high speeds, creating additional hazards. A single sweetgum tree can drop hundreds of these balls annually, leading to a thick, persistent layer of litter. This continuous shedding, from late fall through winter, requires repeated cleanup efforts. Beyond personal property, these balls can also clog storm drains and sewers, contributing to localized flooding issues.