Japanese knotweed, giant hogweed, New Zealand pigmyweed, water fern and Himalayan balsam are nearly always going to need management if they are in your development footprint, you may also have other undesirable species such as three-cornered leek which can blanket areas of woodland or river bank.
A good botanical survey will inform you of what non-native species you have on your site, and liaison with SNH (and SEPA) can then identify which species are considered invasive and need to be managed and to what level as part of your construction project. Under the WANE Act, you may require a licence to work around areas of invasive non-native species.
Each species has its own method of spreading, either by seed or other propagules, vegetative fragments or vigorous vegetative growth. An understanding of the mechanism of spread of each species underpins the best approach for control.
We can provide invasive species surveys and also advice on the best methods of control.
Further information
Few flowered leek can carpet areas of woodland leaving little chance for many of our native woodland species. It reproduces by small, fleshy bulbils which are inadvertently transported around by animals and people.