Weed removal by excavation
There’s no doubt that excavation of weed infected areas is the optimum solution if you’re wanting or needing complete remediation of invasive weeds. In this article we explore which types of weeds are best to excavate, the considerations required when carrying out weed excavation and how to dispose of the excavated waste.
Which weeds can be excavated?
In general most land based weeds can be excavated, however some weeds are best suited to excavation because of their physiological makeup, and others are better suited to other methods of control or removal, such as chemical, biological or mechanical.
Invasive weeds that are woody and have root (or rhizome) systems tend to be the best types of species to excavate, examples of these being Rhododendron, Yellow azalea and Bamboo. Because root excavation ensures all fragments of the roots are removed leaving nothing viable to reproduce, excavation can be used after another type of control method such as herbicide treatment. Species such as Giant hogweed and Buddleia benefit from this combined (integrated) methods approach.
excavation considerations
In general there are 4 main aspects to consider when planning an excavation project, these are listed below.
However, aside from these 4 it’s also vital to have a full Risk Assessment Method Statement (RAMS) prepared for the project. This is an important health and safety document that identifies the steps that must be taken to carry out the excavation in a safe manner.
All projects will start with a site survey, including discussions with the site manager and sometimes, if required, an ecologist before a full brief can be given to the excavation team.
Biosecurity measures will always be factored in to ensure no plant materials are inadvertently taken off site to another area where it can spread.
1. HABITAT
When digging up land it’s vital to consider the habitat and ecosystems that flourish there. This includes flora and fauna, species that may be endangered, or that may be in their hibernation or reproduction cycle.
2. GROUND
What lies in the ground itself is the next consideration. As well as invasive weeds, the ground itself may also contain contaminants such as Asbestos or Lead for instance. These will need to be removed carefully and in a compliant and controlled manner during excavation.
3. ENVIRONMENT
Environmental aspects require careful planning. If the land has supply lines or cables underground then a different form of excavation may be used, such as vacuum extraction which uses high pressured air to gently and safely extract the soils around the utilities.
4. SOCIAL
Social considerations are also important. For instance if the land is near to housing or residential facilities or amenities, then the noise and disruption of moving heavy plant vehicles on and off site will need to be factored in.
what happens with the waste material?
This all depends on the type of plant species that has been excavated. Some invasive plants can be left on site to die off, others such as Bamboo or Rhododendron can be mulched and either removed or left onsite in a suitable place to die off. Others which are noxious weeds, such as Hemlock or Giant hogweed need to be removed completely from site to a landfill licensed to receive noxious waste.
If you’d like to know more about our methods of excavation please contact us to speak to the team.