Once people are aware of invasive plants and their problems, the next question is “so, how do I get rid of them?” There are many ways to control invasive plants, including prevention, cultural, mechanical, chemical and biological options. Weed management involves more than just removing weeds. It is important to set priorities for your land to determine the best approach. A good start is the seven steps to weed management:
1. Describe the property or management area.
2. Inventory and map the property or management area for weeds.
3. Set land management goals and weed management objectives.
4. Set priorities for weed management.
5. Select weed management strategies.
6. Develop an integrated weed management plan.
7. Develop a monitoring plan.
For more information on each of these steps, see the Seven Steps to Managing your Weeds manual.
Integrated Weed Management
The Central Kootenay Invasive Plant Committee promotes Integrated Weed Management. Integrated weed management involves using a combination of appropriate control methods to reduce the weed infestation to an acceptable level, and requires monitoring these activities to evaluate the effectiveness of the control strategy. Click here for more information.
Weed Control Methods
The best control option depends on a number of factors including; knowledge of the potential damage of the weed, relative abundance of the plant species, characteristics of the site, the cost of the control method, and the environmental impact of the weed and the control option. For management methods for a particular weed species, look up the weed on the Weeds BC website.
For an overview of alternative weed control methods developed by the CKIPC, click here. To see a device that can be used to make pulling knapweed easier, click here.
Biocontrol
Biological control is a form of weed management where by the weeds’ natural predators are introduced from their land of origin to attack the weeds in their new environment. These predators, known as “biological control agents”, are usually insects, and are carefully screened before they are released in Canada to ensure that they do not attack any other species. Insects may attack the roots, leaves, stems or seedheads of a plant, reducing its ability to survive and providing more opportunity for native plants to establish. For more information on biocontrol, click here
The goal of biocontrol is not to eliminate the weed but to reduce its population to levels that no longer cause significant environmental or economic impacts. Biocontrol has been used in the Kootenays since the 1950’s. Only some invasive plants have biocontrol agents, including spotted knapweed, Dalmatian toadflax, purple loosestrife, Canada thistle, and hound’s tongue. This long-term method of weed management may take decades to show effects.
Many bioagent species have been released on knapweed in the Central Kootenay area. These agents are primarily root-attackers (weakening the plants ability to store food and water) and seedhead-attackers (reducing the number of seeds each plant produces). Given the large number of insects already released in the area, and the insects’ dispersal ability, many properties in this region likely have these insects present. To find out how to assess your property for insects, download our Bioagent Checklist.