Signs of a Sick Willow Tree in Arlington, Texas

Willows are working against the site here

A weeping willow in Arlington is a tree living outside its comfort zone. Willows evolved on stream banks with permanently moist, slightly acidic soil. Much of Tarrant County offers alkaline clay that swings from saturated in May to concrete in August. The tree survives, but it is stressed most of the time, and stressed trees are what pathogens colonise.

They are also fast and weak-wooded. A willow puts on height quickly, drops limbs readily in wind, and rarely lasts beyond about thirty years here. That is worth knowing before you spend heavily saving one.

Symptoms and what they usually mean

Yellowing leaves with green veins

Iron chlorosis — the alkaline soil is locking up iron the tree cannot then take up. Common, and correctable with chelated iron applied to the soil or injected. Not a disease.

Black or brown spots spreading on leaves, early leaf drop

Willow scab or black canker, both fungal and both worse after a wet spring. Sanitation pruning plus removing fallen leaf litter usually controls it. Repeated defoliation year after year does add up.

Whole branches wilting and dying back from the tips

Often willow blight — scab and canker together — or, if it is progressing fast, a vascular problem. Dieback that moves inward from the tips over weeks warrants a proper look.

Mushrooms or shelf fungus at the base

This is the serious one. Conks at the root collar mean established internal decay, and by the time fruiting bodies appear the structural loss inside is usually considerable. A willow with basal conks near a house or drive should be assessed for failure risk promptly.

Sudden lean, or soil heaving on one side of the trunk

Root plate movement. Do not wait on this one — call the same day and stay out from under it.

What actually helps a struggling willow

• Deep, infrequent watering rather than frequent shallow irrigation — willows want volume, and shallow watering builds a shallow root system.
• A wide mulch ring, two to four inches deep, never touching the trunk.
• Removing deadwood to cut the weight and the pathogen load.
• Checking the root flare is not buried; on willows it frequently is.
• Correcting chlorosis if that is what the yellowing actually is.

When it is time to stop

If a willow has significant basal decay, more than about a third of the canopy dead, and a target underneath it, the honest answer is removal and replacement with something suited to the soil — cedar elm, bur oak, chinquapin oak or Shumard oak all outlive a willow several times over here.

We will tell you which situation you are in. The Arlington assessment visit is free.