Invasive Plant Identification | TP Knotweed

OTHER INVASIVE PLANTS

HIMALAYAN BALSAM CONTROL AND REMOVAL

Like Japanese knotweed, Himalayan balsam (Impatiens glandulifera) is considered an invasive species. The plant was first introduced to the UK in the 1800, with giant hogweed and Japanese knotweed being introduced at the same time. Since the nineteenth century it has spread across most of England, Scotland, Wales and Northern Ireland. Many wildlife trusts organise events to try and remove the invasive plant, but it is now thought that these can do more harm than good, actually helping the plant to spread.

Himalayan balsam flowers between June and October, with purplish pink helmet-shaped flowers, and seed pods that explode when disturbed, distributing seeds up to seven metres from the parent plant. It is mostly found near river banks and on wasteland, although it is also found in residential and commercial areas. Each plant can produce up to eight hundred seeds.

Himalayan balsam is also known as:

  • Impatiens glandulifera

  • Policeman’s helmet

  • Bobby tops

  • Copper tops

  • Gnome’s hatstand

  • Kiss-me-on-the-mountain

HIMALAYAN BALSAM: THE DANGERS

Himalayan balsam can attain reach heights of over two metres, and is aggressively invasive. It typically forms on riverbanks and damp, shaded areas, where it shadows out native plants and restricts access for animals and humans. When the plant does die back, it can leave the area bare of supporting vegetation, making land prone to weathering and erosion.

During the hotter seasons, Himalayan balsam’s flowers attract important pollinators away from native plant species (due to its higher than normal nectar content and long flowering periods). This competition can be damaging for native species, and contributes to their demise.

Remember:

If you are investigating or attempting to remove Himalayan balsam from your land, make sure that you handle it with care due to its propensity to distribute its seeds easily.

CONTROL

Chemical control

This is a common method to control the spread of Himalayan balsam. Chemical control involves the application of specialised weed-killing chemicals to Himalayan balsam plants, and often needs to be consistent over a number of seasons to be totally effective. Due to legislation around spraying chemicals in the wild and near bodies of water, it is safest and most effective to hire professionals that can adhere to laws and best practice.

Manual control

Pulling or cutting Himalayan balsam plants before they flower and set seed is the main form of manual control. Conservation authorities sometimes partake in “balsam bashing” parties, but these must be undertaken with extreme caution, as studies have shown that this can actually help the plant to spread.

For expert control and eradication of Himalayan balsam, get in touch with TP Knotweed today. Speak to us about your customised treatment plan and guarantee by calling 0800 389 1911.

GIANT HOGWEED CONTROL AND REMOVAL

Giant hogweed, like Japanese knotweed, is considered as an invasive species. It was introduced to the UK around the nineteenth century alongside many other similar species, such as Himalayan balsam. It frequents riverbanks, and can often displace other plants and wildlife surrounding its growth area.

Giant hogweed is also commonly found along roads and railways across Britain. Its preferred habitats are those that are relatively unmanaged and have an abundance of light.

This plant’s appearance is fairly distinctive; giant hogweed is tall and has thick stems, and features include white flat-topped flowers, which face towards the sky. In some cases, giant hogweed can be massive, and has the ability to reach over eleven feet in height.

Giant hogweed is also known as:

  • Heracleum mantegazzianum

  • Cartwheel-flower

  • Giant cow parsnip

  • Hogsbane

  • Giant cow parsley

  • Wild rhubarb

GIANT HOGWEED: THE DANGERS

Giant hogweed’s sap is harmful to humans through its ability to cause skin inflammations. The species is phototoxic, which means that if the skin comes into contact with the plant and then direct sunlight, it can cause blisters and burns. In some cases these burns can be severe and require hospital treatment. Always treat this plant with extreme caution!

The highest levels of sap have been discovered during the month of June, so this part of summer is a time to be particularly aware when handling giant hogweed.

CONTROL

As with Japanese knotweed, it is an offence under the Wildlife and Countryside Act 1981 to plant giant hogweed or cause it to grow. There are a number of control measures that can be undertaken to battle giant hogweed.

Chemical control

This is a common method to control the spread of giant hogweed. It is recommended to apply herbicide early in the growth of this species, before the plant flowers and seeds. Chemical control needs to be consistent over a number of years to have any considerable effect. There is legislation around spraying chemicals in the wild, so it is best to do your research and hire professionals that can adhere to laws and best practice.

Manual control

To mitigate the risk of contamination and destruction of nearby plants, manual control and removal of giant hogweed is often favourable. Cutting the plant out from the roots is highly effective, but must be undertaken with extreme care. Cutting the plants themselves will often only encourage faster regrowth and more flowering shoots, and in some cases can help spread the plant’s seeds even further. Strimming and trimming for cosmetic effect is not recommended.

Remember:

If you are investigating giant hogweed in your garden, make sure that you cover your arms and legs and wear gloves. If you are engaging with this species, ensure that you wear a face mask at all times. Due to its potentially harmful nature, giant hogweed needs to be handled with great care.

For expert control and eradication of giant hogweed, get in touch with TP Knotweed today.
Speak to us about your customised treatment plan and guarantee by calling 0800 389 1911.