Biological Agents control Invasive Plants
You have invasive plants on your property and now you must decide what to do about it. There are so many options! What type of plant and how many of them you have will factor greatly into what kind of treatment you use. Today we will talk about biological control. Biological control is the control of a pest by the introduction of a natural enemy or predator. Biological control reunites invasive plants with their natural enemies to suppress infestations to an acceptable level but will not eradicate these plants. The biocontrol agents need the invasive plants for food and reproduction so they will never get rid of the plants entirely. This is about controlling them. Biological control goes in cycles. The more agents there are the less plants there will be. As the plants die there are less plants for the agents to reproduce on, so you start to have less agents and more plants. As there becomes more plants there are then more insects and on the cycle goes. Different insects do different things. Some are root borers, some are seed feeders, some are stem miners, and some are defoliators. Some of the insects do more than one thing to a plant. In the Boundary we have many different agents for many different plants. In the Province of B.C. There are records for 89 separate species and strains of agent that target 38 different invasive plants. For more information search for biocontrol BC to get specific information on insects by target plant.
There are years of research that goes into biological control. Most of our invasive plants are from Europe so that is where the research starts. A biocontrol agent needs so be specific to a certain plant. Sulphur cinquefoil for example was researched for years before they had to give up. The potential insects and diseases that would control it were found to also attack native cinquefoils and strawberries.
So when would you want to use biological control on your invasive plants? If your infestation is large and dense or if it occurs in a sensitive habitat then bio control would be a good option for long-term, effective control.
As part of the free service that the Boundary Invasive Species Society provides, we do site visits to tell you what invasive plants you have and if there are already bio control agents present. Most areas already have a population of agents. If, however your property has a low population or none present at all we can try to source some for you. There is no cost to having us do a bio control release but there are some stipulations. One of our staff needs to do the release and we need to record the location and take photographs.