By Drs. Robert and Sonia Vogl
President and Vice President,
Illinois Renewable Energy Association
We live in the country, yet still feel the desire to experience other natural areas. One of our favorites is a leisurely paddle down a cold, crystal clear river in Wisconsin’s sand country. A few years ago a bottled water company tried to capture the water from this trout stream and sell it in plastic bottles for profit. Fortunately people successfully fought the endeavor. More recently large dairy operations have sprung up in the area potentially threatening both the availability of water and its high quality. To date the stream remains intact but in a growth oriented culture new threats to environmental quality are never ending. At some point infinite growth on a finite planet becomes impossible.
Our friends of many years have owned a small formerly abandoned farm which has served the family well as they are avid outdoors people with a keen interest in ecology. With everyone’s busy schedules we still plan at least one fall trip with them.
This fall, as we approached the farm we noticed a nearly denuded hillside just north of their woods. We wondered why anyone would do that to such a beautiful natural site. We soon learned that oak wilt had once again struck. Our friend pointed out where trees had grown in their farmyard last year but were no longer there. He is a retired biology professor; his father was Bob’s first ecology professor. So naturally, much of our conversation revolves around field biology. That day, our conversation began with the cause, symptoms and impacts of oak wilt.
Oak wilt is a disease caused by a fungus which enters a tree and stops of the flow of water by plugging vessels in the vascular system. While all oaks are susceptible some such as red oaks are highly susceptible. It is most commonly spread by root to root contact but can also spread by fungal spore mats which attract sap feeding nitidulid beetles. The beetles can carry the spores from an infected tree to another tree with a fresh wound spreading the disease. Clues to its presence and recommendations for controlling the disease can be found online.
The hillside oaks were infested with oak wilt so the entire stand was removed as a sanitation measure to limit the spread of the disease.
Our friend reminded us of his father’s theory that the presence of oak wilt might have been a contributing factor to the survival of the native prairie.
When oaks became particularly dense, the wilt would have killed off many, creating openings for the prairie to expand.
Seventy years ago ecologist and environmental philosopher Aldo Leopold chronicled the life and death of the Good Oak whose offspring also lived and now died in Sand County; “We mourned the loss of the old tree, but knew that a dozen of its progeny standing straight and stalwart on the sands had already taken over its job of wood-making.”
Our canoe trips are less frequent than in earlier years but remain an important and inspiring part of our lives. It is always good to maintain contact with old friends and reconnect with a natural setting that rekindles our spirit as it has for other generations.