Tree Care and Maintenance

Seasonal Tree Care Tips: Spring 2024
Invasive Ivy Removal 

Ivy (Hedera spp.) is the most common invasive plant in Lake Oswego and the biggest threat to urban forest health and sustainability. It is an aggressive species with no natural enemies that grows and reproduces quickly, outcompetes native plants like wildflowers and ferns, and can rapidly grow up tree trunks with detrimental effects. Ivy competes with trees for water and nutrients, deprives tree bark of normal contact with air and microorganisms, can completely overgrow and kill trees, and the weight of ivy increases susceptibility to wind stress and the risk of branch or whole tree failure.

Ivy is easy to identify by its waxy evergreen leaves. It is a woody vine with a shallow mat-like root system that is a poor choice for erosion control. Ivy is commonly found growing along the ground, up trees, and on walls or other obstacles. Ivy tolerates drought, frost and deep shade, but climbs trees and other tall objects to access sunlight using modified roots to adhere to its host. Flowers and berries produced in late fall and early winter turn to seed in the spring and spread by birds, but ivy also reproduces from rootlike stems and sprouting fragments.

Manual removal of ivy is labor intensive, but the most effective means of control. When manually removing ivy, it is critical to remove as much ivy stem and root as possible because of its ability to regenerate. At the same time, try to minimize soil disturbance and protect desirable plants. Wear gloves and long sleeves as the sap is known to cause a reaction in some people.

Property owners can remove ivy from trees by cutting the vines at chest height in a ring around the trunk with pruners, loppers or saws. Pull the lower portion of the cut vine off of the tree trunk carefully to avoid bark injury, and pull or dig out the attached roots. Clear a 3- to 6-foot ring around the base of the tree to help prevent or postpone re-growth up the trunk. The upper portion of the vines can be left on the tree because it will die back.

Learn more about the detrimental effects of ivy and how to remove it by visiting these sites:

Please check back quarterly for more tree care and maintenance advice!


 Please check back for more seasonal tree care and maintenance advice!

Link to Tree Care and Maintenance Archives


Winter 2024: Clean and Sharp Pruners

Fall 2023: Mediterranean Oak Borer

Summer 2023: Supplemental Watering and Mulch to Prevent Drought Stress in Trees

Spring 2023: Aphids

Winter 2023: Pruning: Standards and Best Practices

Summer/Fall 2023: Emerald Ash Borer

Winter/Spring 2022: Nesting Season

Fall 2021: Healthy Trees are Defended Trees

Special Edition: After the Storm

Winter 2021: What is an Arborist?

Fall 2020: Soil Management  

Summer 2020: Retaining and Creating Snags for Wildlife

Spring 2020: Mulch: Numerous Benefits and Easy Application

Winter 2020: Tree Planting: To Stake or Not to Stake?

Fall 2019: Insects and Diseases

​Summer 2019: Drought Stress Revisited

Spring 2019: Trees and Construction

Winter 2019: Topped Tree

Fall 2018: Autumn Leaves

Summer 2018: Emerald Ash Borer

Spring 2018: Pruning Young Trees

Winter 2017: Tree Related Storm Damage

Fall 2017: New Tree Selection and Planting

Summer 2017: Trees and Turfgrasses

Spring 2017: English Ivy Removal

Winter 2017: Recognizing Tree Risk

Summer 2016: Drought Stress

Fall 2016: Preparing Trees for Winter


Additional Tree Care Resources:

National Arbor Day Foundation The Morton Arboretum
Oregon Department of Forestry Tree Care Info
ISA Find an Arborist Alliance for Community Trees
Oregon Department of Forestry  


Right Tree in the Right Place

Use this handy guide for assistance in choosing the right species of tree based on the constraints of a site, such as overhead wires, narrow plant strips, and proximity to structures.

"Right Tree Right Place" - helpful information such as "Use this guide for assistance in choosing the right species of tree based on the constraints of a site, such as overhead wires, narrow plant strips, and proximity to structures."

"Master Plant List" - a guide to the plants that are acceptable for mitigation requirements in Lake Oswego.