Why Are So Many of Pasadena’s Oaks Dying?

Stacking rocks around the roots and trunks is bad for oaks (Photos – Pilar Reynaldo)

As an avid walker in the San Rafael neighborhood, I often see dead Oaks. Every time I see a dead Oak it breaks my heart, they’re native to the area and home to our native birds and other creatures.

By Pilar Reynaldo

Many residents do not know how to care for these trees. Unwittingly they water excessively thinking because it is summer the tree will need more water. Oaks do not need or want summer watering. They have deep root systems where they store the water they acquire in the winter.

Another issue is stacking rocks or other items around the roots and trunks. Decorative piling keeps the roots wet which becomes an invitation for pathogens to grow. Connecting or having a sprinkler head hitting the trunk of the tree is another NO NO. The saturated trunk once again becomes an invitation for fungus and other pathogens to make a home in your tree. Do not plant annuals under your tree which have different watering needs.

Ivy and Oaks have completely different watering needs (Photo – Pilar Reynaldo)

Best practice is to

• prune your tree to prevent limbs from being hit by trucks and other tall vehicles,
• shut off any sprinkler heads hitting your tree,
• remove all rocks and decorative items along the trunk and roots,
• keep your oak leaf litter on the ground as it acts as mulch, and
• contact a certified arborist if you have questions.

On the corner of Colorado Boulevard & Melrose is a grove of Oaks which provide beautiful shade to those who play at San Rafael Park. The Pasadena Department of Parks and Recreation has under planted these trees with Ivy. Ivy and Oaks have completely different watering needs, Ivy is also a very aggressive climber, often the limbs of the Oaks are wrapped with Ivy. The park also has these trees connected to irrigation which is often on when I drive by in the evenings. Does the city not employ an Arborist who knows best practices for these majestic trees?

If everyone is more mindful about the needs of these amazing trees they should be around for hundreds of years.

Pilar Reynaldo is an avid walker, community activist, master gardener, lover of nature trees, and advocate for pedestrian friendly – safer – greener – streets.