Prescott, Arizona has long been known for its beautiful Ponderosa pines, alligator junipers, and diverse mix of native trees. But in recent years, these trees have been under increasing stress. Prolonged drought conditions, coupled with rising temperatures and the absence of meaningful monsoon rains or winter snowpack, have created a crisis for our local forests and urban landscapes.
One of the most effective ways homeowners and property managers can help their trees survive—and even thrive—during this drought is by providing supplemental deep watering.
Why Watering Matters
Trees rely on consistent moisture deep in the soil profile to support their root systems, maintain internal hydration, and fuel photosynthesis. During drought, this moisture is depleted well below the surface, beyond the reach of light rainfall or irrigation systems designed for lawns and shallow-rooted plants. Native trees such as Ponderosa pine and juniper are adapted to dry conditions, but they are not immune to prolonged water deficits. Without adequate hydration, trees experience slowed growth, thinning canopies, needle drop, dieback, and eventually death.
Water and Tree Defenses
A well-hydrated tree is a resilient tree. When a tree has access to deep soil moisture, it can maintain healthy internal pressure and continue to produce protective compounds like resin and pitch. These substances are essential in helping trees defend themselves against bark beetle and engraver beetle attacks. Resin flows can physically push out boring insects and help seal wounds, preventing further infestation. In contrast, drought-stressed trees often lack the energy and water pressure needed to produce sufficient pitch, making them vulnerable targets for beetles seeking weakened hosts.
The Current Bark Beetle Threat
In the Prescott area, we are seeing a sharp increase in bark beetle and engraver beetle activity. These pests are opportunistic and target stressed, weakened, or dying trees. Once they infest a tree, they bore through the bark and disrupt the flow of water and nutrients, which quickly leads to decline. Outbreaks can spread rapidly, especially in neighborhoods and woodlands with clusters of stressed or unwatered trees.
How to Water Effectively
- Water slowly and deeply at the dripline of the tree (the area under the outermost branches), not near the trunk.
- Water once per month during dry seasons. A deep soak of 4-5 hours using a soaker hose or slow-running hose is ideal.
- Adjust frequency based on soil conditions and tree species, but always prioritize deep, infrequent watering over shallow, frequent watering.
- Avoid watering during the heat of the day to reduce evaporation loss.
Long-Term Benefits
Supplemental watering not only helps trees survive drought—it can also extend their lifespan, reduce the risk of pest and disease outbreaks, and maintain the beauty and ecological value of your property. Healthy trees provide shade, improve air quality, support wildlife, and increase property values.
Final Thoughts
In these challenging times, your trees need you more than ever. With just a little monthly care in the form of deep watering, you can make a significant impact on their health and resilience. If you’re unsure about the condition of your trees or need help with developing a drought mitigation plan, don’t hesitate to reach out.