Answers to Your Questions: Does Dappled Willow Pose a Threat to My Pipes?

I am considering planting a dappled willow, but I am concerned about its reputation for having invasive roots that can potentially damage pipes. Could you tell me if there is a real risk and what precautions I should take before planting such a tree?

Answer

You’re right to ask, because willows generally have a reputation for having a vigorous root system, which can sometimes be problematic. That said, the dappled willow(Salix integra ‘Hakuro-Nishiki’) is not one of the high-risk species.

Unlike large tree willows, such as Salix alba or S. babylonica, which are known for their long, powerful, and invasive roots, the dappled willow is a small shrub, sometimes grafted onto a stem, with a much more limited root system. Its roots are estimated to generally extend in a radius equivalent to its crown, which can reach up to 3 meters (10 feet) in height and width after several years. However, this extent may vary depending on soil, moisture, and cultivation conditions.

s Shrubby willows such as shrimp willow do not usually pose a problem for sanitary systems. Their roots will not actively seek to penetrate pipes unless they already have a leak or weakness. In fact, it is mainly cracked or leaking pipes that attract roots, regardless of the species. Thin roots can then sneak in, grow, and, over time, block the passage or enlarge the crack.

That said, even a “well-behaved” shrub can become problematic if planted too close to damaged pipes. It is therefore not so much the aggressiveness of the root system that is the problem, but rather the presence of cracks or leaks in the plumbing.

A Few Precautions

To minimize any risk, it is recommended that you plant your dappled willow at least three meters away from any water pipes, drains, septic tanks, or foundations. It is also advisable to ensure that your installations are in good condition before planting. In well-drained soil without excessive moisture, the roots of this willow do not usually cause any problems.

Despite the poor reputation of large willows, the shrimp willow remains a safe choice for small residential gardens, as long as its mature size is respected. You will be able to enjoy its variegated, elegant foliage without fear of damage to underground infrastructure.

More Information

• Should I Prune My Dappled Willow in the Fall?
• Major Outdoor Plumbing Issues You Should Avoid
• Trees with Invasive Roots