Healthy, functioning forests are dynamic systems that decompose organic matter, cycle nutrients, and provide habitat for diverse wildlife. A healthy forest is never free of insects, diseases, and other disturbances. Oregon forests cover approximately 30 million acres of the state and consist of federal (60%), private (35%), state (3%), tribal (1%), and other public (1%) ownership. In Washington County, approximately half of the county (over 230,000 acres) is commercial forestland.
Components of Forest Health
Tree vigor is the overall health and growth of a tree, and takes into account several factors, including foliage color, foliage volume, and tree growth. Stress can make trees more vulnerable to pests or disease, and can result in decreased vigor. Stress may include overcrowding, tree wounding, soil compaction, drought, or too much water.
There are four primary tree health problems: insects, diseases, abiotic factors, and physical damage. Insects are a natural part of the forest ecosystem, but some can have detrimental effects on tree health. They can be very specialized, targeting certain parts of the tree. For example, there are foliage feeders, twig feeders, and large branch and trunk feeders. Diseases are another type of tree health problem, primarily caused by fungi. Diseases come in a variety of forms such as foliage diseases, trunk/stem diseases, root diseases, and parasitic plants. Abiotic (non-living) stressors may include heat waves, drought, unseasonal frost, and high winds. Physical damage to a tree is most common around homesites, where there a closer proximity to heavy equipment and human activity. Tree wounds provide entry points for insects and diseases. A combination of tree health problems can worsen conditions.
A healthy forest includes dead trees, which provide valuable homes for many wildlife species. Fallen dead trees decompose to replenish organic matter in the soil.
The most important first step to improve forest health is to improve tree stand vigor. Thinning is one way to do this. By thinning out smaller, weaker trees, the most vigorous trees are left to grow. Other ways to improve tree health include pruning and growing a mix of species rather than just one. Healthy trees are also maintained by avoiding harmful practices and activities, such as tree wounding, soil compaction, trenching, backfilling, or over-watering.
Highlights of Accomplishments
The District has provided technical assistance to a small number of forest owners due to limited staff capacity. On properties where the District implements other programs, District staff make an effort to include forestland, if it exists, in conservation plans for these properties. District staff also help NRCS implement a variety of cost-share programs related to forest owners.
District staff have given several presentations to forest owner groups on topics such as invasive plant species and District services. Relevant news articles written by District staff are circulated to these groups to include in their publications and member correspondence.
- Landowners express interest in forest health practices.
- Forest health practices are implemented after landowners receive education and conservation planning assistance.
- Forests in Washington County are highly functioning, diverse ecosystems, managed for both wildlife and economy.
By the end of 2020, the District will improve the awareness of and implementation of forest health practices by private forest landowners in Washington County.
Resources on Our Website
Landowner profiles in forestry: Hyla Woods
Oak conservation (coming soon!)