Invasive Species

Non-native plants - usually introduced originally as garden plants, but which self-propagate like weeds. These are now spreading around the country outcompeting native UK species and in some cases damaging property.

Japanese Knotweed - RHS

Japanese knotweed (Reynoutria japonica syn. Fallopia japonica) is a weed that spreads rapidly. In winter the plant dies back to ground level but by early summer the bamboo-like stems emerge from rhizomes deep underground to shoot to over 2.1m (7ft), suppressing all other plant growth. Eradication requires determination as it is very hard to remove by hand or eradicate with chemicals. New legislation now covers its control

Groundsure-Japanese-Knotweed-Home-Holiday-Home-Let-Property.jpg

Your Legal Responsibility - Boshers Insurance

The first point to state is should the plant appear on your premises, it’s your responsibility to eradicate it. New laws state that landowners can be found liable. Especially if there is proof they knew about an infestation of Japanese knotweed and failed to deal with it properly.

Identification - Inside Conveyancing

As Japanese knotweed is a perennial plant, its’ appearance changes throughout the year. Knowing how to spot this weed as the seasons pass is vital to ensure you don’t miss those all-important signs.

Management - Britannica

Japanese knotweed thrives in areas with disturbed soil, such as farmsteads, trails, and roadsides, where the conditions are prime for seed germination and for the spread of the plant’s rhizomes. The plant can tolerate drought, full sun, deep shade, high temperatures, and high soil salinity and is frequently found along streams and rivers. Japanese knotweed is allelopathic, meaning it releases chemicals into the soil that inhibit the survival of surrounding plants.

Horsetail or Mare's Tail - 'Equisetum arvense'

Is horsetail as bad as Japanese knotweed?

While Horsetail is a native plant species and therefore not legislated, many have found it to be the cause of more damage to infrastructure than Japanese Knotweed. It is well known for breaking through tarmacadam, block paved areas, car parks and destroying landscaped areas.

Developers who have failed to identify and remove Horsetail during construction can find this plant re-appearing through newly laid driveways and footpaths.

Horsetail has deep roots (up to 5ft) and not only spreads by spores in the air, but also underground by rhizomes.

It's very important to kill off the first stalks that produce spores to prevent them from reproducing and spreading further later on. Even though these are likely to regrow, hoeing them out before they spore is an effective way of controlling their spread.

Cut back as much of the weed as you can in early spring, before the pinkish-yellow domes that contain the spores ripen. Work carefully to avoid spreading the spores, and place all debris into a sealed plastic bag to dispose of it.

What is the best weed killer for horsetail?

'Kurtail Evo' is a professional solution, giving the best control of Horsetail/Mare's Tail and most other weeds (including grass). SBK Brushwood Killer is also a good solution and perfect for non-professional use.

1 - 'Roundup' doesn’t kill horsetail. The weed’s waxy leaves give them protection from the majority of topical herbicides, and the plant’s resistance to Roundup’s active ingredient makes this a huge mistake.

2 - Using ground-covering plastic or thick mulch does not work either. Horsetail will thrive in the low-light, low-oxygen environment that you create when you cover the area.

3 - Pulling the weed by hand, will not work - it will grow back again and again from the deep root beneath.

Where to buy?

SKB - Brushwood - For unlicensed use (£24.45 - with Kplus)

ProGreen.co.uk - Details for Horsetail

ProGreen - 'Kurtail' - (£28.99)

ProGreen - Kurtail Evo - (Safety details)

Kurtail at 'A1 Lawn'

Diamond Horsetail Killer

Repeated applications will be necessary. 3 or 4 times a year, for a couple of years.

When you buy a professional use pesticide you and/or the end user must ensure that the product is legally used in line with the Approved Code of Practice set out by The Food & Environment Protection Act 1985 (FEPA) & Control of Pesticide Regulations 1986 (COPR).

Himalayan Balsum

Other names: - 'Indian Balsam, Garden Balsam, Policeman’s Helmet'

Himalayan balsam is an Invasive Non Native Species (INNS) which is now widespread along many rivers. Since its introduction balsam is the UK’s largest annual plant.

Thriving in damp marshes and by rivers, it dies back in winter leaving river banks bare of vegetation and prone to erosion. Eroded soil forms silt which smothers invertebrates and fish eggs, causing eco-system change.

What’s the problem and how do we tackle it? Why has Himalayan Balsam spread so quickly?

• Seed pods explode, throwing seeds up to seven metres.

• Each plant has 600 to 2,000 seeds.

• Seeds will float downstream and spread along watercourses.

• Seeds survive for about three years.

• In the UK it has no pests or diseases and can grow to two-three metres in height, outcompeting all other plants.

• Bees are so attracted to balsam they reduce pollination of native plants.

• Germination is staggered over several months and seedlings grow quickly, out-competing all other plant species.

Cutting – It is possible to cut back Himalayan to just above ground level before it flowers, which prevents flowering and seeds forming. As Himalayan Balsam is an annual plant, it will not grow back from the roots the following year. Should be repeated for at least two seasons.

https://www.environetuk.com/invasive-species/himalayan-balsam

If sighted in Dorset report it here -

The Dorset Environmental Records Center

DERC