Observing street tree installation can often be like the old saying, “watching sausage being made.” Many times, arborists have to tolerate trees being planted in what is often referred to as tree crypts, where little consideration is given to the soil, space for roots, and tree selection. Expense and lack of communication are often sited as the main reasons for the neglect. Lack of communication is exacerbated by separate departments or contractors overseeing the planning, engineering, and installation. Have you used a successful strategy to have street trees installed properly? Please share it.
Arborists are often asked to assess tree hazards on a property and are taught to look at tree health, target, and size. Jesse Milton, in his casual research, reports that in 38% of trees that he has observed to fail, the defect was either not visible or there was no defect. It is no wonder that arborists often recommend to take down healthy-appearing trees near commercial and residential structures. The decision is particularly tough when the tree is a specimen hardwood that is healthy. To complicate matters is the bigger issue of probability; typically, it is more likely for a person to get in a car accident than for the tree to fail. Arborists are left with measuring the risks and rewards of leaving a tree. Due to liability issues, these trees are typically removed. Is this the right course of action or are there alternatives?
At our recent program, “The Elements of Tree Health,” Dr. Kim Coder discussed the 20 essential elements. Often arborists in the field will sample the soil to better understand the situation, but what about sampling the tree? The sample is typically extracted from the crown, where growth is active, using either a leaf or small twig about one inch long, which is then sent to the lab. Arborists can then compare and contrast what is in the soil vs. the tree. Let us know if you have used tree sampling for chemical analysis in your work. Click on the headline to leave a comment.
Dr. Kim Coder, of the Warnell School of Forestry and Natural Resources at the University of Georgia, shared his lastest research on essential “Elements of Tree Health” at the September 24 GUFC program at the Griffin campus. While only 1% of tree material is composed of essential elements, failure to secure all essential items leads to primary deficiencies, secondary symptoms, compounding problems, and metabolic dysfunction. This 1% consists of what he refers to the “essential 20.” To lay the foundation for the class, he had to talk chemistry, and did an excellent job of making it accessible. His research is laying the ground work for arborists and urban foresters to not just test soil conditions but also sample the actual tree for the essential 20 before subscribing treatment. Thanks Dr. Coder.
The composition of your urban forest is often overlooked. Diversity of species is important for both aesthetic and health reasons. Today, Quercus phellos (Willow Oak) and Ulmus parvifolia (Chinese Elm) are two of the more popular street trees in Georgia. The reason being is they are very hardy being able to tolerate both wet and drought conditions. However, to just plant these two species could make you susceptible to a disease like sudden oak and wipe out a substantial portion of your forest in one swoop. What street trees other than Quercas and Ulmus have you had success with?
Observing street tree installation can often be like the old saying, “watching sausage being made.” Many times, arborists have to tolerate trees being planted in what is often referred to as tree crypts, where little consideration is given to the soil, space for roots, and tree selection. Expense and lack of communication are often sited as the main reasons for the neglect. Lack of communication is exacerbated by separate departments or contractors overseeing the planning, engineering, and installation. Have you used a successful strategy to have street trees installed properly? Please share it.
