Pussy willows are beautiful and eye-catching, but like all plants, they’re not immune to issues. If you've noticed something off—maybe leaves turning brown, strange bumps on branches, or even white powder on the foliage—you're likely dealing with one of several common willow tree problems.
These issues can show up as physical damage, insect infestations, or even fungal infections. Some are just cosmetic, while others can weaken the tree if left untreated. Knowing what you're looking at is the first step in taking care of your plant the right way.
This page breaks down the most common symptoms you might see on your pussy willow and links them to their probable causes—from weak wood that breaks in storms to fungal diseases like powdery mildew and rust. If you’re concerned about willow tree diseases or pests, don’t worry—we’ll help you understand what’s happening and what you can do about it.
Let’s look at the problems, what causes them, and how you can treat or prevent them to keep your pussy willow healthy and thriving.
| Pussy Willow Problems | |
|---|---|
| Symptoms | Probable Cause |
| Break In Storms | Weak Wood |
| Bark Attacked; Leaves Curled and Distorted | Aphids |
| Holes in Leaves and Girdled Twigs | Bagworm |
| Branches Swollen And Distorted; Holes; Sawdust And Sap Stains At Base Of Trunk | Borer |
| Holes in Leaves | Caterpillars |
| Leaves Consumed; Conspicuous Tawny Egg Masses Present | Gypsy Moth |
| Foliage Turns Pale or Mottled | Lace Bug |
| Leaves Wilt and Turn Brown | Midges |
| Leaves Become Distorted and Cupped | Psyllids |
| Leaves Are Skeletonized | Sawfly |
| Leaves and Branches Encrusted With Small Bumps | Scale Insect |
| Leaves Discolored | Thrips |
| Leaves Mined and Discolored | Weevil |
| Leaves Covered With White Powder | Powdery Mildew |
| Yellowish Spots and Dark Pustules On Leaf Undersides | Rust |
| Leaves Spotted; Turn Brown; Fall Prematurely | Leaf Spot |
Breaks In Storms means Weak Wood
Willows have weak, brittle wood. They often split or break in storms, especially under the weight of ice or wet snow. There is no effective protection from this problem, except to site the trees in areas that are somewhat sheltered from wind.
Like many willow varieties, a pussy willow tree can suffer from structural issues due to its soft, fast-growing wood.
Leaves Covered With White Powder indicates Powdery Mildew.
If you notice white or dusty spots on your pussy willow leaves, it might be an early sign of a fungal infection like powdery mildew. Powdery mildew is caused by a fungus that develops mostly on the upper surfaces of the willow leaves. It looks like whitish blotches. If the mildew is serious, spray the willow leaves thoroughly with wettable sulfur once or twice at weekly intervals starting as soon as the whitish coating of the fungus is visible. Collect and discard all aboveground refuse in the fall.
For more information see file on Dealing with Fungal Disease.
Yellowish Spots And Dark Pustules On Leaf Undersides due to Rust.
Rust is one of several common willow diseases that can affect the health and appearance of your tree’s foliage. Some rust diseases that are caused by fungi attack willow leaves. They are signaled by lemon yellow spots on leaf undersides, that later develop into spore-bearing pustules. A severe infection will cause the willow leaves to drop. Although rust infections are not considered serious, they can defoliate young trees. Collect and destroy fallen leaves and prune out affected branches. Spray willow foliage with a copper fungicide.
For more information see file on Dealing with Fungal Disease.
Leaves Spotted, Turn Brown, Fall Prematurely means Leaf Spot.
Leaf spot is a typical willow tree fungus problem, especially during humid conditions or when cleanup is neglected. A variety of fungi cause leaf spot disease on willows.
These infections are distinguished by yellow, brown or black dead blotches on the leaves. Often spots come together to form larger patches of dead tissue. Some may cause premature defoliation of the tree. Because leaf spot fungi over winter on diseased fallen leaves, a thorough fall clean up is the best treatment. Gather and destroy the fallen leaves and other nearby garden debris. During the growing season spray affected trees with copper fungicide when the disease causes considerable defoliation.
For more information see file on Dealing with Fungal Disease.
Common Questions About Pussy Willow Problems
What causes black spots on willow leaves?
Black spots on willow leaves are usually caused by fungal diseases like leaf spot, willow scab, anthracnose, and rust. These thrive in moist, humid conditions, especially when there’s poor air circulation. Other factors like pests (e.g., aphids), sooty mold, overwatering, and nutrient deficiencies can also contribute. To help prevent it, prune for airflow, avoid overwatering, clean up fallen leaves, and use a fungicide if needed.
Why are my weeping willow leaves turning yellow?
Yellow leaves on a weeping willow are usually caused by watering problems, nutrient deficiencies, pests, or stress from weather or soil conditions. Too much or too little water can both lead to yellowing.
A lack of nutrients like nitrogen or iron is also a common reason. Sometimes pests like aphids or fungal diseases like rust can be to blame. To fix it, check soil moisture, feed with a balanced fertilizer, look for pests, and make sure your tree isn’t stressed by poor drainage, extreme weather, or high winds.
What is the best willow tree fungus treatment?
The best way to treat fungus on a willow tree is to prune infected branches, clean up fallen leaves, and improve air circulation around the tree. Water carefully—avoid overwatering or spraying leaves. For serious infections like rust or scab, use a fungicide with chlorothalonil, myclobutanil, triadimefon, or mancozeb, following the label instructions. It’s best to treat early in dry weather and consider applying to nearby trees to stop the spread.
How to prune a pussywillow bush?
Prune a pussywillow bush in late winter or early spring, before new growth begins. Start by cutting away any dead, broken, or diseased branches. Then trim older stems back by about one-third to encourage fuller, bushier growth. You can also shape the plant by trimming wayward branches and making cuts just above a bud.
For a bigger refresh, try coppicing—cutting the whole bush down low every few years to promote strong new shoots. Always use clean, sharp tools.
