Many of Oak Allee’s revered trees are in danger of dying or being removed due to old age, disease, and other natural causes.
Oak Allee, located between Graham Chapel and Brookings Quadrangle, is home to some of Washington University’s oldest trees, many of which were planted in the years following the 1904 World’s Fair.
Campus horticulturist Paul Norman says he is fighting to save the oaks, but currently not much can be done.
“In an urban environment, the lifespan of most trees is less than ten years,” Norman said. “In rural areas, some oak trees can live as long as 200 years.”
Trees in urban locations struggle against pollution, inclement weather conditions, and damage from automobile accidents. Not long ago, one of the trees in Oak Allee had to be taken down after it was struck by lightning.
Recently, Norman had to remove three trees near Graham Chapel because of rot or disease. Additionally, seven trees located in front of Brookings were cut down for the same reasons. The remainder of the trees are in decline and Norman expects that in the next five to seven years, most of the trees along that path will be dead.
The university hired an independent forester, Skip Kincaid and Associates, to evaluate the trees in Oak Allee. Their opinion only confirmed what Norman had discovered: although the trees looked healthy, the bases were rotting and the tops were hollow.
“We make an effort to preserve what we have through pruning and other methods, but sometimes the trees have to come down,” Norman said. Weakened trees are more susceptible to disease and occasionally diseases such as Hypolxylon Canker hasten the death of a tree by several years.
A practice known as topping, which WU used in the 1970’s, has also affected the lifespan of the trees. Topping involves shortening the crown of a tree by cutting the branches down almost to the trunk. Eventually, the university realized that topping did not lengthen the life of a tree, but it instead caused the branches to go limp and fall out about 10 to 15 years after the initial process. Topping obstructed the trees’ ability to obtain food through photosynthesis and reduced their leaf surface.
The weakened trees present a hazardous environment for students and visitors to campus. Bill Wiley, manager of maintenance operations, noted that some trees have branches that are in danger of cracking or falling, creating a perilous situation for people walking along sidewalks throughout campus. Those trees must be removed sooner to prevent any mishaps.
Students have noticed the diminishing number of trees along Oak Allee and hope the university will do more to preserve the trees that are still standing.
“If they aren’t dead yet, don’t cut them down,” said junior Surinder Aggarwal.
Plans to replace the trees are in the works, but not much can be done in the Oak Allee area until all of the trees are removed. Once the trees are gone, replanting can commence and the new saplings can receive the proper amounts of sunlight for maximum growth. If the university planted new trees while the older ones are still standing, the overhanging branches or deep, winding root patterns would stunt the growth of the newer trees.
To contact Erin Harkless, email her at [email protected].