Trees are desirable to Northern Virginia land owners for the aesthetic and monetary value they can add to a property.
In urban and suburban areas, trees are valued for shade and natural beauty. In rural areas, and on larger tracts of land, trees may be valued for timber and the habitat they provide for game. Regardless of their purpose, keeping your trees healthy is important for the value of your Northern Virginia land.
The foundation of tree health
Healthy trees provide shelter and shade for humans and animals. Unhealthy trees, on the other hand, can create hazards and liabilities. A diseased, rotten tree, for example, poses a danger to nearby cars, buildings, and people if it topples overs. Therefore, maintaining tree health is important.
The key to tree health is to choose species that are suited to your local climate and property conditions. This goes beyond simply choosing trees that will grow in your USDA growing zone. Altitude, soil type, and amount of rainfall are all important considerations when selecting trees to plant on your property.
Northern Virginia has a wide range of climates and growing conditions. Trees that grow well in the mountains and valleys of the Shenandoah Valley may not grow well in coastal areas with saltier soils. If you are unsure of which trees will grow best in your area, the best people to contact for advice are your local extension service, a forester, or an arborist. Choosing the right tree and planting it correctly is the first step to tree health.
Signs of health and signs of trouble
A healthy tree will have a single leader or central branch. However, some species thrive with more than one leader. Some examples include fruit trees. Whether the species is a single leader tree or can support multiple leaders, each one should have a sturdy main trunk without any major cracks, holes, or round outgrowths on the trunk. A tree with an abnormal number of central leaders is at a greater risk of splitting or falling in a storm.
The next health check involves standing under the tree and looking up. The canopy of the tree should be full, lush, and only allow a small amount of light to pass through. The leaves should be a deep green color, not pale, yellow, or brown. The leaves should be abundant, full-sized, and the proper shape for the species.
You should also check for obvious signs of insect infestation, fungus, and other diseases. The bark is like the skin of the tree, protecting the tree from dangerous infections. The bark should be thick, unbroken, and not peeling away from the central wood. Some trees, such as the shagbark hickory, can have the appearance of bark falling off, but the bark is actually securely attached. Insects can damage the tree bark and make it vulnerable to disease.
Other signs of insect or disease infestation include:
- Dead or broken branches
- Loose or peeling bark
- Leaves that look wilted
- Bare patches in the canopy
- Branches without leaves
- Holes in leaves
- Yellow or pale leaves
- Patches that look like rust on the leaves
- Visible insects or evidence of them
- Sap oozing from the tree
- Trees that are falling off deciduous trees in the summer or spring
- Fruit and trees that do not bear fruit as expected
- Galls (round balls or knobs) growing on the branches or stems
- Excessive moss growing on the tree
- A vertical crack in the trunk of the tree
- Woodpecker holes, or damage from animals
- Black flowers or shoots in the spring
- Fungus that look like shelves on the base of the tree
- White, powdery substance on the leaves indicates powdery mildew
- Any type of spot or discoloration on green leaves
- Brown, dry needles on pines
These are general guidelines to look for on any tree species. However, certain trees have diseases that are specific to that species. For instance, quaking aspens are susceptible to aspen canker, elms are susceptible to Dutch Elm disease, and ash trees are susceptible to emerald ash borer infestations. Knowing the signs and symptoms of species-specific diseases is important. If you are unsure if something is cause for concern, you may wish to have the tree examined by an arborist or forester.
When in doubt, consult an arborist
A healthy tree should be putting on regular growth every year. The trunk should expand every year, even if only slightly, and it should put new growth on the branches, too. If a tree does not appear healthy, or you observe telltale signs of disease or insect infestation, you should consult with a local arborist as soon as possible. Most problems do not just go away on their own. It is best to seek help early—an arborist or forester may be able to save the tree before it is too late.
Healthy trees are an asset to your property, but keeping them healthy requires consistent attention. If you’d like to learn more about tree health in Virginia, the Virginia Cooperative Extension offers a wealth of free informational resources.