Growth regulators can reduce new growth by 40-90% with a residual control of 3 years/application. This is a great tool for situations where tree size is a concern. For example, we walk a lot of properties where river birch are planted too close to homes as corner landscape accents. As they mature homeowners often become concerned. Treatment with a growth regulator combined with pruning are effective management options. Other reasons for applying growth regulators may be to promote fibrous root growth. Studies have shown that growth regulators can provide several tree health benefits which can assist in rejuvenating trees showing signs of environmental stress.