Timber Stand Improvement

When the cold rolls in and the leaves fall, it signals the beginning of Timber Stand Improvement (TSI) season for Polk County Conservation staff. Most TSI work takes place during wintertime in order to minimize the risk of harm to both people and the environment.

Winter work allows staff to minimize park-user exposure to the TSI process. This is critical because timber work is inherently risky given the use of heavy machinery and power tools, and the potential for falling debris.

Working on trees in the winter also prevents the spread of disease from plant to plant. Because native tree species are more susceptible to diseases like oak wilt during the summer months, doing TSI work during the winter helps limit plant infections.

TSI is an important conservation practice which aids in the restoration of Iowa’s natural environment. Without it, remaining woodland areas in the state will be choked out by
invasive species such as honeysuckle. Polk County helps ensure the safety of both the natural environment and people through its work.

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