1. General information about Japanese Knotweed
2. Comparison, treating Japanese Knotweed with Roundup Pro Biactive vs Loram 24 (Tordon 22K)
3. Treating Japanese Knotweed with Roundup Pro Biactive
4. Treating Japanese Knotweed with Loram 24

1. About Japanese Knotweed

Japanese Knotweed was introduced to the UK in 1825 and widely planted as an exotic garden ornamental before the invasive nature of the plant became clear. Japanese Knotweed is probably the most invasive plant in Britain and is scheduled under the 1981 Wildlife and Countryside Act so that it is an offence to plant or cause it to grow in the wild. In addition under the Environment Protection Act (1990) Japanese Knotweed is classified as ‘controlled waste’ and must be disposed of at a licensed landfill site in accordance with the Environment Protection Act (Duty of Care) Regulations 1991.

Growth habit

Fleshy, red shoots appear in the early spring from an extensive underground network of stems (rhizomes). The shoots can reach 1.5m by May and 3m by June. Long racemes of cream flowers appear in late summer and dieback occurs at the first frost of the autumn, leaving the leafless stems to remain throughout the winter. The rhizomes from one plant can be 2m deep and 7m across.
In the UK Japanese Knotweed does not produce viable seed, except in the rare instances of hybridisation with other similar introduced species. Many areas of the country have campaigns to eradicate Japanese Knotweed and Roundup Pro Biactive plays an important role by controlling the weed with maximum safety to operators, the public and the environment.

2. Comparison, treating Japanese Knotweed with Roundup Pro Biactive vs Loram 24 (Tordon 22K)
 

3. Treating Japanese Knotweed with Roundup Pro Biactive

• Chemical control of Japanese Knotweed in aquatic areas needs Environment Agency approval. You will need to fill in form WQM 1 and submit it to your local EA office
• Always clear the previous year’s growth during the winter. This evens up the new stems and makes spraying easier
• Treated plants take up to 6 weeks to show symptoms. Only remove plant material when there is no further sprouting. Only re-spray if there are no visible signs of dieback after 6 weeks
• As with most broad-leaved perennials, optimum control will be achieved from treatment at flowering in August or September but before die-back
• Treatment late in the season is the most effective because the glyphosate is transported deep down into the underground rhizome structure along the natural flow of plant nutrients down for winter storage. Japanese Knotweed is sensitive to frost so late season applications should be made in advance of the first frosts
• For established stands it is important to plan an effective management programme over several years as repeat applications may well be necessary, either to control very large plants, with their associated underground mass of rhizomes, or to control those plants which were missed by earlier applications due to shading. Sites should be monitored for at least three years

How to control Japanese Knotweed

Foliar spray at Flowering
This is the optimum timing. Use of specialist extending hand lances is recommended where plants are 2-3m tall. Spray the underside as well as the upper surface of the leaves.

Two foliar sprays at 1 metre stem height
Spray the Japanese Knotweed at 1-1.5m tall, in late May and repeat on any re-growth later in the season once they reach 1.5m again. This technique can be used where stands are particularly thick, as part of an integrated control programme or where long lances are not available.

Weedwiper
Applications using a hand held weed wiper have proved successful. This method can be useful where treatment of nearby vegetation is to be avoided or for spot treatment of small re-growth. It has very high success rates, but is labour intensive.

Stem injection
This recent introduction from the USA can be used to treat small stands (particularly by water) and new invasions, and to tidy up escapes from eradication control programmes. The tool uses a needle to inject directly into the stem rather than cutting the stem down. Progreen sells InjectorDos, an injection applicator with the facility to ‘dial-in’ a pre-determined metered volume of spray liquid to be dispensed.

4. Treating Japanese Knotweed with Loram 24

Loram 24 herbicide features and benefits:

    * Contains 240 g/litre (21.1% w/w) picloram as potassium salt
    * Highly effective against pernicious / troublesome species such as Japanese knotweed and ragwort.
    * Extended action - less sprays required
    * Grass selective - prevents soil erosion
    * Acts through both foliage and roots - different application methods available
    * Can be used as close as 1 metre from water sources

What does Loram 24 herbicide control?
Loram 24 herbicide controls a wide range of perrenial and annual broad leaved weeds in non-crop land. It is also effective against woody weeds and scrub. It will not harm grass when used at the correct dosage.

Difficult weeds controlled include: Japanese Knotweed, Ragwort, Thistle, Bramble & Docks.

Apply to Japanese Knotweed during active growth stage for use on roads, weeds can obstruct sightlines and road signs and create a fire risk. They can cause structural damage to road surfaces, and can create a habitat for vermin. When using  Loram 24 herbicide, grass cover can be maintained to prevent soil erosion and improve aesthetic appearance.

Off-track rail
Weeds create hazardous conditions for maintenance operations on railway trackside. They can obscure sightlines and create a fire risk. Rail track structure can be damaged and weeds can also interfere with signal wires and points.

How is  Loram 24 herbicide applied?
Loram 24 herbicide is mixed with water and applied through a hand-held knapsack sprayer or vehicle mounted sprayer. For road or railway siding weed control, the best treatment time is late winter or early spring. For grassy areas such as embankments, excellent results can be achieved with treatment coinciding with periods of vigorous growth.

Care should be taken on slopes to prevent leaching into areas where desirable trees and shrubs are present.

How does Loram 24 herbicide work?
Loram 24 herbicide contains picloram which is absorbed through plant leaves and roots. The product is rapidly absorbed by the foliage and roots of the weeds and translocated, or moved, throughout the plant causing disruption in the plant's growth and ultimate weed kill. Its residual action prevents development of germinating weeds. Loram 24 is a selective herbicide. Leaf symptoms will develop 4-10 days following treatment.

Loram 24 also offers additional environmental benefits. It is safe to grasses, which encourages the re-colonisation of the natural flora and prevents any erosion, this is particularly important in areas such as embankments on the railways and highways. It also helps in the management of habitats, providing and safeguarding wildlife corridors, as well as helping to generate a bio-diverse environment

Loram 24 should be sprayed at 5.6 litres/ha when weeds are actively growing and before they get too big. With Japanese Knotweed being so prolific - growing up to 10 cms a day - if it does get too big then the advice is to cut the weed back, and re-treat the re-growth when it is a more manageable size (approximately 1 metre high).

For more information on Roundup Pro Biactive click here
To view our knapsack sprayers click here
For more information on our Stem Injection kit click here
For more information on the weedwipers we sell click here
To view more information on Loram 24 click here