Question

What are three methods used to help control invasive species?

Answer 1

Manual Control
Mechanical Control
Chemical Control

Explanation:

For the sake of this answer we will assume the invasive species has already invaded, so that Prevention becomes obsolete. Now lets look at each control method.

1. Manual Control
   This includes digging, flooding, destruction and removal of nests, hand-pulling, burning and general destruction of the invasive species by hand. This is most useful for small infestations and is the most environmentally friendly, yet is the most labour intensive and least effective for larger populations.

2. Mechanical Control
   Mowing, hoeing, cutting, tilling, girdling, chopping and constructing barriers to the invasive species using tools and/or machines. This method is best for medium-large infestations in areas which pose a safety risk due to terrain, and when used in conjunction with chemical control it can be extremely effective, However, depending on the time spent and the size of the infestation, using mechanical means can get quite expensive as it needs to be done repeatedly, and it can cause some environmental damage.

3. Chemical Control
   Includes pesticides, herbicides, fungicides and insecticides. The least labour-intensive option, chemical control on its own is usually the most effective option, as it can target specific species and will kill them guaranteed. However, this has the potential to be the most environmentally-damaging option, as chemicals could attack other species and stay in the area long after the invasion has been dealt with.

http://dnr.wi.gov/topic/invasives/control.html
https://www.coastalisc.com/how-to-control-invasive-plants

I hope I helped!