Japanese knotweed threat

Recent unseasonably low temperatures may well have postponed the peak growing season for Japanese knotweed by a few weeks but, in reality, this invasive, non-native plant species has proved continually resilient to most climatic conditions, as Japanese Knotweed Control’s joint managing director, David Layland explains.
Originally native to eastern Asia and China before being introduced into Europe in the 19th century as an ornamental plant, Japanese knotweed’s rapid, and at times devastating, spread is indicative of its ability to adapt to a wide range of climatic conditions. No matter how wet our summers get, our how cold our winters, the UK’s varied and unpredictable weather is never likely to seriously diminish the knotweed threat.
It’s true that in winter, or even in the unseasonably cold conditions of recent weeks, the plant will remain dormant – indeed the rhizome material can lie dormant for up to 20 years – but it will not die. Once temperatures increase, the knotweed soon rejuvenates and quickly catches up with its growth schedule.
In recent years, our work has taken us to all corners of the British Isles and the damage caused by widespread knotweed never fails to surprise. In the remote Hebridean Western Isles, for example, where Japanese Knotweed Control has carried out a number of treatment programmes, the climate and geography present their own particular environmental challenges. Yet even here Japanese knotweed is widespread and increasingly impacting on a number of development projects.
Many plants don’t cope well with the harsh Scottish climate, less still the bracing conditions of the Outer Hebrides, but whilst the shallow peat soils, high winds and salt air have meant that, like many plants on the islands, knotweed’s growth has been stunted, its spread has been no less prolific, even ousting many native plant species in its wake.
The one weather condition that does affect Japanese knotweed, though unfortunately not in a positive way, is heavy rainfall. Knotweed, as well as other invasive species such as Himalayan Balsam and Giant Hogweed, are all growing in increasing numbers along our river corridors, often with serious impact on the biodiversity of the riparian and aquatic environment. As rain falls and water levels rise, there is increased risk of rhizome spread along the length of the river and many river authorities are now recognising and addressing this problem.
With UK weather conditions unlikely, however, to have any impact on reducing knotweed growth, the return of the growth season once again sees it largely left to professional treatment specialists to try and tackle the problem. For Japanese Knotweed Control, the treatment techniques that we’ve employed throughout the winter, for example excavation and dig and dump, tend to make way for our preferred method of stem injection treatment.
The stem injection equipment, which injects a given dose of glyphosate herbicide directly into the plant stem, is increasingly recognised as achieving maximum control and specific to the plant species, with no impact on the surrounding vegetation and wildlife.
The knotweed absorbs the herbicide into the rhizome with a much faster absorbency rate than that of foliar spraying and, crucially, much greater accuracy. Results can be seen within two weeks as the weed goes dormant and shows visible signs of foliar decay. This also enables any canes missed during the initial treatment process to be readily identified and treated with a re-application.
Most significantly, stem injection is not dependent on weather conditions such as wind or rain and can be safely used in most site conditions without any risk of spray-drift or run-off.
TEl : 0845 643 1168
Weed Control fabrics are enjoying increased exposure as an alternative to pesticides when it comes to controlling unwanted weed growth in both residential and non-residential applications. Importantly not all landscape fabrics are the same.
There are various forms of fabric on the market from woven, needle punched non woven, spun bond polypropylene as well as the DuPont Plantex range. Basis is weight is often considered a key selection criteria, but this is not always an accurate measure for critical performance factors of the products. Weed control fabrics need to provide air and water permeability, a long life time and a barrier to airborne seeds in order to provide a fully functioning layer in a wide range of applications.
When considering a product the performance cost ratio should be considered. Take the performance versus the cost of a product by comparing individual products’ data comparisons for water and air permeability, tensile strength and puncture resistance, its ability to resist airborne seeds and the products uniformity/quality.
DuPont has undertaken rigorous comparison tests at its experimental farm station in France where the results have shown that DuPont™ Plantex® provides competition beating results in all the performance criteria.
Wipe out the weeds !
Rather than spraying, a fast and far more cost-effective method of wiping out weeds is to consider the Wessex Rotowiper weed wiper.
Ideal for paddock, pasture and turf care the first thing you notice is that it uses much less chemical than spraying and, most importantly, it targets the vulnerable underside of weed leaf, hitting it where it hurts without killing grass or clover.
A wiper carpet specifically designed for weed wiping uses UV-protected interwoven loops to hold moisture drops. The 45 litre chemical tank coats an adjustable height roller with weedkiller and the wiper roller rotates in the opposite direction to travel, coating the underside of weed leaves thoroughly and efficiently, as well as wiping the stem.
A pump is controlled remotely from the safety and comfort of the seat of an ATV or UTV, the rotor is spirally welded for maximum strength and two check valves in the centre of the roller keep it evenly coated with the chemical.
There is a neoprene rubber strip that prevents any risk of spray drift and aids foaming, so the Rotowiper is the ideal solution for working near water coarses without the danger of pollution. Productivity is also increased because the weedwiper can be used on windy days where sprayers can’t. The Wessex Rotowiper is available in a 2.4m width and the large wheels and wide wheelbase keep it stable and steady in use. It fits any standard ball hitch, it can be triple mounted for controlling larger areas and three-point linkage versions are also available.
Tel 01420 478111

Fully Biodegradable Weed Control Fabric

A completely organic weed suppression blanket, which fully breaks down to nutritious matter over 3 to 5 years leaving no synthetic residues, was successfully launched by Hy-Tex (UK) Limited last year.
Ecotex MulchMat (which also passes the cigarette burn test) has proved to be an effective, easy to use and economical solution for low maintenance weed control and moisture conservation in planted areas and has a very low production carbon footprint.
It may look and feel like conventional non-woven, petrochemical based weed control fabric but Ecotex MulchMat is made purely from an environmentally friendly alternative called Polylactic Acid (PLA).
PLA is made from 100% annually renewable, starch rich vegetables and production requires fewer fossil fuel resources and generates less greenhouse gases than traditional plastic fabrics. Furthermore, Ecotex felt is the only weed control fabric certified to the stringent EN 13432:2000 test for compostability.
In addition, Ecotex MulchMat is stronger, more durable and easier to handle than any previous “degradable” fabrics and resists airborne seed settlement far better.
Finally, the fabric is ideally suited to the problem of controlling weeds on sloping beds as the visually pleasing, colour fast, earthy brown fabric does not need to be hidden beneath bark mulch (which is prone to slipping
Tel 01233 720097
High standard of work and service

Specialist weed control contractor Complete Weed Control has brought its technical expertise into play to ensure that the Celtic Manor Resort in South Wales is always in pristine condition – and continues to flourish with a long-term maintenance programme.
Director of Golf Courses & Estate Management James McKenzie MBE is convinced the fantastic-looking resort is in no small way due to the high standard of work and service provided by Complete Weed Control (South Wales).
Following a positive testimonial from a greenkeeper at a nearby golf course, CWC has been working with James for almost twenty years
Since then, CWC have become a regular visitor to the resort with work including moss control, weed control, disease management and last minute cosmetic spraying applications as well as emergency works.
“Complete Weed Control are experts in their field and we see them as an extension to our in-house team,” explains James
A major innovation in recent years has been the introduction of new technology to apply pesticides more accurately as part of a continuing drive to apply fewer quantities and conform to the EU sustainable use directive (SUD).
“The technology of weed control and spraying applications is quite sophisticated these days, and CWC is widely recognised as the number one contractor in the industry. They put a lot into research and development and really look after us. What we receive from them is a total solution, not just spraying, but a scientific approach and the best expert advice for the future. It’s very cost-effective too, and we receive excellent value for money.”
TEl 01325 324 277
Photo James McKenzie MBE, Director of Golf Courses & Estate Management at Celtic Manor relies on Complete Weed Control for a total solution programme.

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