Tree Care & Protection

Tree Care & Protection

Glendale’s protected trees play an important role in the city’s urban forest, providing shade, wildlife habitat, and environmental benefits throughout the community. Proper care helps keep these trees healthy and ensures they can thrive for generations to come.

The information below provides guidance on caring for protected trees, proper pruning practices, and when to consult a qualified arborist.

IMPORTANT

Certain work involving protected trees may require a permit from the City. Before pruning, removing, or performing construction near a protected tree, review the Rules & Permits page to confirm whether approval is required.

Caring for Protected Trees

Protected trees require thoughtful care to remain healthy and stable over time. Damage to roots, excessive pruning, or changes to surrounding soil can weaken trees and increase the risk of disease or structural failure. Property owners and residents can help protect trees by following these basic care practices:

Protect the Root Zone

Keep the area around the base of the tree undisturbed. Avoid digging, grading, or trenching near the trunk, since roots often extend well beyond the visible canopy.

Maintain Healthy Soil Around Trees

Healthy soil allows tree roots to absorb water and oxygen. Limit heavy vehicles, equipment, or material storage beneath trees to prevent soil compaction.

Water Trees Properly

Provide deep watering during extended dry periods so moisture reaches the root zone. Water slowly and evenly to allow the soil to absorb moisture.

Monitor Tree Health

Check regularly for signs of stress such as thinning leaves, branch dieback, or visible damage. If you notice changes in a tree’s condition, consider consulting a qualified arborist.

Keep Trees Free of Attachments

Protect the bark by avoiding nails, signs, ropes, lights, or other hardware attached to the trunk or branches. These items can damage bark and create entry points for pests and disease.

For guidance on safe pruning practices and when professional assistance may be needed, see the sections below.

Proper Pruning

Pruning helps maintain tree health, remove dead or damaged branches, and improve structure when done correctly. Improper pruning can weaken trees and make them more vulnerable to pests, disease, and structural failure.

If you are unsure how to safely prune a tree or whether a permit is required, contact the Forestry Section at (818) 548-3950 before beginning work. For larger pruning projects or work involving protected trees, the City may require assistance from a qualified arborist.

When pruning trees, keep the following guidelines in mind:

Prune Conservatively

Remove branches gradually and avoid cutting large portions of the canopy at once. Pruning more than 25 percent of a protected tree’s canopy may require a permit.

Remove Dead or Damaged Branches

Clearing dead, broken, or diseased branches helps protect the tree and reduces the risk of falling limbs.

Make Clean, Proper Cuts

Branches should be pruned at the branch collar (where the branch meets the trunk or larger limb) to help the tree heal properly.

Avoid Harmful Pruning Practices

The following pruning methods can severely damage trees and are not allowed under Glendale’s tree protection regulations, even with a permit.

Topping

Cutting live branches back to large stubs to reduce a tree’s size. This practice weakens tree structure and often leads to poor regrowth.

Hat Racking

Removing large sections of branches and foliage so the tree resembles a coat rack or hat stand. This practice severely stresses trees and damages their natural structure.

Lion’s Tailing

Removing interior branches so leaves remain only at the ends of limbs. This can make branches more vulnerable to breakage and reduces the tree’s stability.

Hire a Qualified Arborist

Some tree care activities require specialized knowledge and equipment. When work involves large branches, construction near trees, or potential impacts to protected trees, it may be best to consult a qualified arborist. Arborists are trained professionals who specialize in tree health, pruning, and proper tree care. They can help assess a tree’s condition, recommend appropriate maintenance, and prepare required documentation for permit applications when necessary. Working with a qualified arborist can help ensure that tree care is performed safely and in accordance with Glendale’s tree protection regulations.

When to Consider hiring a professional arborist

Professional assistance may be helpful when:

  • Pruning large or high branches
  • Assessing tree health or structural concerns
  • Preparing an Indigenous Tree Report for permit applications
  • Planning construction near protected tree
  • Evaluating trees that appear diseased, damaged, or hazardous

When hiring a tree care professional, consider working with trained and licensed professionals who specialize in proper tree care.

The International Society of Arboriculture (ISA) maintains a directory of certified arborists who are trained in proper tree care, pruning, and tree health management.

Before hiring a tree care company, verify that the contractor holds a valid license through the California Contractors State License Board (CSLB).

Consulting arborists specialize in tree evaluations and may prepare technical reports for development projects, tree preservation plans, or permit applications.

For additional guidance on selecting a qualified tree care professional, view the City’s Professional Tree Care Guide.

Protecting Trees During Drought

Extended dry conditions can place stress on trees and affect their long-term health. Even well-established trees may struggle when soil moisture is limited, especially during prolonged periods of drought. Providing proper care during drought conditions can help trees remain healthy and resilient. Residents can help protect trees by following the tips below:

Water Trees Deeply

Apply water slowly so it penetrates the soil and reaches the tree’s root zone. Deep watering encourages stronger roots and helps trees withstand dry conditions.

Water at the Right Time

Watering in the early morning or evening helps reduce evaporation and allows more moisture to soak into the soil.

Water the Area Beneath the Canopy

Most tree roots are located beneath the outer spread of the canopy. Apply water throughout this area rather than directly against the trunk.

Use Mulch to Retain Moisture

A layer of mulch around the base of the tree can help retain soil moisture and regulate soil temperature. Keep mulch a few inches away from the trunk to prevent moisture buildup against the bark.

Watch for Signs of Drought Stress

Trees experiencing drought stress may show signs such as:

  • Leaf drop or thinning foliage
  • Wilting or curling leaves
  • Dead branches or branch dieback
  • Dry or cracked soil around the base of the tree

Helpful Guides & Resources

The resources below provide additional information about tree care, professional services, and Glendale’s urban forest programs.