Although it is often said that weeds are "merely plants in the wrong place", they can be disruptive and even destructive - in urban environments lifting paving slabs and causing trip hazards, trapping litter, attracting vermin, presenting a fire risk and generally lowering the tone of an area to such an extent that vandalism occurs.
In sporting facilities weeds can interfere with ball bounce and roll, reducing the playing experience. Then there are the particularly nasty types such as giant hogweed that cause serious skin irritation or Japanese knotweed that can make buildings unstable and turn development land into a no-go area.
In many amenity situations we cannot turn a blind eye and excuse weeds as "nature taking over". In lots of cases weeds have to be destroyed. But the use of chemicals remains challenging. It could be argued that the fewer applications made the better, for spray operative and the environment. For real effectiveness, residuals are an answer.
The news that agrochemcial manufacturer Belchim Crop Protection has added an "amenity vegetation (around) recommendation" to the Chikara label is most welcome. Furthermore, the same label recommendation is expected to come through the regulatory system shortly for Katana.
Chikara and Katana contain the active ingredient flazasulfuron and are already established as the key products of choice for residual total weed-control management in both the public and commercial sectors.
The addition of amenity vegetation to the label enables grounds maintenance organisations to combine efficient delivery of a low active ingredient with effective and long-lasting weed control. The products fill the void left by the regulatory loss of residual products such as Casoron G (dichlobenil), Ronstar and Festival (oxadiazon).
"There has not been an effective product for use in shrub beds for a few years now due to regulatory constraints that prohibited the use of many older products in the amenity sector," says Belchim Crop Protection senior technical adviser Peter Ingram. "Chikara/Katana aim to fill the void left by the loss of these products and will deliver season-long weed control across all porous surfaces found within the amenity industry. The products are only available via our trained and qualified distributors Rigby Taylor, Nomix and Sheriff Amenity."
Rigby Taylor chemical manager Peter Corbett adds: "The industry has been crying out for an effective product for use in shrub beds. We have been working very closely with Belchim and are delighted that we are now able to offer a highly cost-effective solution to help manage weed control in such areas."
Used correctly, Chikara - either on its own or in a tank mixture with other products - will also deliver season-long weed control across all porous surfaces, including gravel car parks, around street furniture and on kerb edges.
Premium selective herbicide
There is also good news for those managing amenity and sports turf. This year Headland Amenity launched a premium selective herbicide for the control of broadleaved weeds in turf and professional lawn care. Called Redeem, this three-way selective herbicide controls a wide range of weeds found in golf fairways, tees, sports pitches, lawns and other amenity grass areas.
Redeem, which contains Clopyralid, 2,4-D and MCPA, is effective against daisies, clovers and plantains. Control is achieved at low application rates - up to half the rate of many other selectives - ensuring a lower amount of active ingredient is required for efficient control. Grass areas can be re-seeded as early as six weeks after application and, importantly, Redeem can be applied using knapsack sprayers as well as boom-mounted equipment.
David Layland, joint managing director at treatment specialist Japanese Knotweed Control, says the scale of the Japanese knotweed problem in the UK has not abated, forcing the Government to implement new legislation in a bid to stem costs and make landowners assume greater responsibility for treating their own land.
Indeed, homeowners who now fail to control Japanese knotweed face criminal prosecution under new antisocial behaviour laws. People can be fined up to £2,500 for failing to control the invasive plant. The legislation also applies to Himalayan balsam and giant hogweed. Previous legislation covered prosecution of anyone planting Japanese knotweed - deliberately or accidentally.
The cost of trying to eradicate the problem plant from Britain has been estimated at more than £125bn. The cost of clearing the weed from just 10 acres of the London Olympics site was more than £70m. Injecting herbicide into the stems of Japanese knotweed plants remains one of the most reliable treatments.
"Stem injection is commonplace in the UK on a significant number of riverbank, parkland and amenity projects. Its growing popularity in the EU has been boosted by countries such a Belgium coming down firmly on the side of stem injection as the most appropriate and ecologically sound herbicide application method," says Layland, who is also joint managing director at Stem Injection Systems (SIS).
Academic research by the University of Liege, involving tests of different chemical herbicides, applications and mechanical treatments, has concluded that stem injection using glyphosate-based herbicide is the most effective system and the Belgian government wasted no time in ordering several units from SIS.
Specialist contractor The Knotweed Co chooses Monsanto's Roundup ProBio for much of its work in controlling invasive and troublesome weeds such as Japanese knotweed, giant hogweed, bamboo and horsetail. Applications include spraying, stem injection and weed wiping. Director Brian Taylor is impressed with the formulation, saying he has seen "improvements to a tried and tested brand".
He adds: "Roundup has always been an excellent product, very effective and safe to use, but the Roundup ProBio formulation is even better. It is rainfast in just one hour and the take-up to the plant is much improved. It is also very safe so we can be confident about COSHH assessments."
On Japanese knotweed, Taylor says: "We find that application of Roundup ProBio to the stems as well as or instead of the leaves offers improved targeting because the leaves can often be high up in the air, therefore treating the stems minimises the risk of drift and exposure for the operator."
Increasing regulation, the loss of key products and concerns about glyphosate emphasise the importance of an integrated approach to weed control. Indeed, legislation such as the EU Sustainable Use Directive and Water Framework Agreement outlines the growing obligation to minimise the use of chemicals in public spaces to protect human health as well as the environment.
Launched in spring 2015 and premiered at IoG Saltex, held at the NEC in November, Cardley Wave systems combat weeds with 100 per cent hot water at 98 degsC and enable organisations to achieve an integrated approach to weed control. The range of systems available includes manual and machine-mounted equipment to deliver a weedand moss-killing strategy that is effective and environmentally friendly.
But systems go further than weed control. With just one machine and a variety of lances, solutions can also be found to drain jetting and chewing gum or graffiti removal as well as deep street cleaning.
One authority to try the Cardley Wave is Aberdeen City Council. Communities, housing and infrastructure convener councillor Neil Cooney says: "Protecting the environment is extremely important to the city council and this excellent system allows us to get rid of weeds simply by dousing them with hot water. We can also use it as a quick and efficient way to get rid of unsightly chewing gum and graffiti.
"More and more countries are banning the use of certain types of weedkillers so it makes sense for Aberdeen to stay ahead of the legislation and take the best environmentally friendly course of action now available to control weed growth."
New sprayers: what you need to know
On 26 November last year, sprayer operatives who had previously relied on "grandfather rights" lost those rights and had to gain a certificate of competence or stop spraying.
This year on 26 November, the Sustainable Use Directive requires owners of pesticide-application equipment to ensure that the kit has been properly inspected, tested and certificated.
It is thought that the new rules could lead to a rush to buy new equipment, with owners and operators deciding that their old sprayers simply will not make the grade.
Equipment that has to be tested by that date includes air-blast sprayers, trains sprayers, equipment mounted to aircraft and - wait for it - all boom sprayers and all other forms of pesticide application equipment that is more than five years old.
If it is less than five years old, the equipment must be tested by the time of its fifth anniversary. Boom sprayers wider than 3m will then require testing every five years. For boom sprayers of 3m or less, the test interval is six years.
The legislation also covers slug pellet applicators, micro-granular applicators, weed wipers, fogging, misting and smoking equipment, seed treatment equipment, sub-surface liquid applicators and other forms of specialist application equipment.
Knapsacks, handheld and pedestrian-controlled equipment do not need to be formally tested but should be inspected by 26 November and then need to be regularly inspected by a competent person. Records must be kept of the results and any repairs made.