Are Mulberry Trees Bad for Plumbing?

Mulberry Tree Growth

• Of the numerous species of mulberry trees and cultivars grown in the United States, all develop fast-growing, wide-spreading shallow root systems. In their natural woodland habitats, mulberries tend to prosper and are found most densely in the fertile soils near streams and rivers. Although demonstrating some drought tolerance, mulberry trees grow better when the soil is evenly moist and well-drained, but a consistent underground water source ensures the trees are always hydrated.

Root Growth Insight

• All trees grow the majority of their roots in the top 24 inches of soil, and they spread widely from the trunk. Most trees do not develop a deep taproot. A few roots may grow downward to anchor the tree, but most roots spread far and wide into the soil where water, warmth and nutrients are most plentiful. Like willows, mulberry trees develop surface roots in moist soils. Roots are opportunistic, growing out in all directions to absorb nutrients and moisture. Once a section of a mulberry tree's root system grows into a wet area around plumbing, those roots grow more vigorously. The other roots around the tree continue to grow outward only where conditions remain favorable. Tree roots do not "seek" or abruptly change direction to grow only to an area of a plumbing pipe break or septic system field.

Planning

• If you have irrigation piping, water supply lines or a septic tank on your property, choosing to plant or retain an existing mulberry tree is an unwise decision. No plumbing line remains sealed or lasts forever. Septic systems deposit effluent underground through conduits, supplying water and nutrients to the soil. Once a drainage opening or damage crack exists, a tree root can then grow into the pipe. As the roots grow, they apply pressure to cracks and can cause them to enlarge and cause further fractures.

Insight

• Older water and sewerage lines were constructed with concrete, porcelain or metal materials, which deteriorate and crack. These lines are replaced with modern composites such as PVC, which are more durable. If your property still has older plumbing lines, do not plant a mulberry tree, or cut down the problematic tree. Even if new PVC plumbing lines are present, do not plant mulberry trees within 50 feet of them.