Chapter 6: Invasive Weeds
6.4 Are Agronomic Weeds Also Invasive Weeds?
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This is an important question. Certainly some of the weeds presenting difficult challenges to farmers do have invasive-like qualities, including spreading in the field. However, that does not necessarily mean they are truly invasive. For example, a challenging weed found in a grain crop field placed instead in a natural system may not even survive because the environmental conditions are far different. In the field crop system there is a constant disturbance that allows the invasive-like weed the unique niche it needs to thrive over other weeds. Similarly, if the farmer were to adjust how they are managing their field, like going from a conventional tillage system to a no-till system, suddenly the troublesome weed may not thrive under new environmental conditions.
To recap, when a weed is considered truly invasive, it is able to survive and spread across ecosystems.