One of the first things our arborists do is assess the trees to determine if any of them have a disease or if there are any safety concerns. This is very important because many diseases can spread from one tree to another. If it's determined one or more trees have a disease, we decide if the disease can be safely treated or if the trees must be cut down.
The Assessment Process
We assess the health and soundness of each tree by thoroughly examining its visible roots, trunk, leaves and canopy. There are 13 things we look at to determine the health of a tree (there are variations in the assessment process depending on species; this is a general guideline). They are:
1. Trunk Wounds - Firm, 100% intact trunk bark is a sign of a healthy tree. Numerous woodpecker holes and 40% to 80% missing bark means the tree is unhealthy.
2. The Presence Of Mushrooms - No visible mushrooms on the tree means it's healthy. Visible mushrooms on its trunk or large branches means its unhealthy and unsafe.
3. Co-Dominant Branches - Trees with a strong central leaders and no visible co-dominants are usually healthy.
4. Annual Branch Extension - Healthy trees show 10 inches or more of annual growth. Trees with 2 inches or less of annual growth are unhealthy.
5. Annual Trunk Diameter Growth - Healthy annual tree trunk diameter growth is 3/4 of an inch or more. Trees with 1/4 inch or less of growth are not healthy.
6. Trunk Flare - Trees with visible trunk flare are healthy. Buried trunk flare makes a tree unhealthy.
7. Surface Roots - Healthy trees have surface roots that radiates out from its trunk like the spokes of a wheel.
8. Soil Drainage Rate - Water must be able to drain into the soil at the base of a tree at an infiltration rate of 1/2 inch to 3 inches per hour it can support a healthy tree.
9. Density Of Canopy Leaves - Dense, thick, canopies is another indicator a tree is healthy. A sparse canopy means it's unhealthy.
10. Canopy Perimeter Shape - Healthy tress have canopy shapes that are oval or round.
11. Leaf Color And Appearance - Healthy tress tend to have large, dark green leaves. Unhealthy trees often have small, yellowish leaves which have scorch marks covering 50% or more of it.
12. Branches On The Trunk and Trunk Base - Healthy trees don't usually have visible small branches on their base or main trunk. Unhealthy trees often do.
13. Mulch Application - Healthy mulch application forms a dish-like shape around the tree's base. Thick mounds of mulch that touch the tree trunk is an unhealthy application.