Source Population Treatments

What is a Source Population? How are they managed?

  • A source population is a large area covered with one or more invasive species. In ISN’s service area, major source populations are usually invasive Phragmites, Japanese knotweed (and other invasive knotweeds), baby’s breath, and autumn olive.
  • Source populations are a risk to our region because, as the name implies, they act as a source.  Fragments of the plants or their seeds can travel to new areas, creating satellites (and eventually a new massive source). Of course, these populations are negatively impacting our native habitats.
  • Treatment of source populations is very difficult, making these populations lower priority for ISN.  They’re often large enough to be very expensive, and the areas usually span multiple ownerships and require many years of treatment.  The goal in treating these massive areas is to use large-scale funding to bring the population down to a manageable, “maintenance” level where local funding or groups may take over.
  • Some source populations may not be able to be treated because of these many obstacles.

What is ISN doing about Source Populations?

Through funding from the Environmental Protection Agency, US Forest Service, and the Michigan Invasive Species Grant Program, ISN has been able to work on source populations throughout our service area