Weeds are no fun to deal with. Whether it’s knotweed, ragwort, or giant hogweed, there are different removal solutions available depending on the type of weed. Here are five common solutions you will encounter when you call a professional weed remover.
Herbicides, also known as chemical control, is a kind of treatment that is applied via a sprayer, most often a knapsack sprayer. This is one of the most efficient ways to treat large monocultures of invasive plant weeds. It can also be used to treat specific spots of weeds that are too difficult to remove manually.
Japanese knotweed and other deep rooted species of weeds will continue to regrow year after year even after treatment. While their growth will not be as expansive as it would be without treatment, it will still require follow up spray treatments at the right time of year. Spot treatments will continue until there is no regrowth.
Stem injection is a method used often for Japanese knotweed control. It includes a higher concentration of the ingredient used in spray applications. There are many other recommended herbicides for spray applications that don’t allow for stem injection.
Instead, this method uses a special herbicide injection tool where the active ingredient in the spray method is injected directly into each cane of Japanese knotweed. The injection occurs about 30 centimetres from the base, or between the first and second nodule. After this, smaller amounts of herbicide mix are injected into the cane with a different specialist tool.
Glyphosate based products are commonly used for injection. They work best when applied in the early autumn, around September. Like the spray method, regrowth will continue year after year, but it will not be as bad as its original appearance. You will need to hire follow up treatments each autumn. However, the follow up treatments will only be spot treatments instead of full injection sequences.
Excavation and encapsulation are a solution only for extreme weed infestations. Invasive plants will be mechanically removed from the ground. The plants, considered a contamination, will be buried on site at least 5 metres deep. They will also be wrapped in a protective membrane to avoid soil contamination. The only time this method is used is if the infestation site is very large.
There is another kind of excavation removal option called Dig and Dump. This is when the plant has contaminated the soil. The soil is excavated 3 metres deep. This depth extends to 7 metres deep if there is Japanese knotweed above ground.
The soil is loaded onto Lorries and sheeted securely to be transported to a licensed landfill site. The soil is classified as controlled waste and is only allowed to be removed by a licensed waste carrier.
A soil screening is a method to purify the soil that has recently seen an invasive plant infestation. The contaminated soil goes through a screening machine on-site. The roots, or rhizomes, are separated from the soil. Rhizomes are removed and thrown into a licensed landfill site. This allows the soil to be used again on site.
There are other invasive plants that have their own particular removal methods. For Giant Hogweed, the spraying or stem injection method is used during the growing season of March to August. Giant Hogweed takes many years to completely eliminate and should only be done by a professional because of the toxic sap. Excavation is also an option for Giant Hogweed that has contaminated the soil.
Ragwort can be removed in two ways. The most effective way when dealing with individual plants is to dig them out. There is a specially designed ragwort fork that has central tines, ensuring complete root removal. This tool is used when the ground is soft after wet weather. Spot spraying is another removal method. This is perfect for areas with lots of ragwort plants contained in small paddocks.