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Development of zero and minimal herbicide regimes for controlling weeds on hard surfaces and determining their emissions - PS2802

This project aims to develop knowledge and provide demonstration that will determine the feasibility of integrated and zero herbicide use on hard surfaces in the UK. It will be implemented jointly by East Malling Research (EMR), Kent County Council, Kent Highway Services (KHS) and the Environment Agency (EA). Any man made impermeable surface, such as concrete or asphalt (road, pavements, playgrounds etc) and including railway ballast that is not intended to bear vegetation is classed as a hard surface. Methods for the control of weeds on hard surfaces fall into two categories, preventative and remedial. The former are generally implemented during the laying (e.g. joint sealing) and are designed to stop weed growth, whereas the latter include the use of herbicide and non-herbicide methods to kill or inhibit growth of established weeds. In practice, most weed control is remedial. Non-herbicide methods of weed control fall into two further categories thermal and mechanical. Common thermal methods include flaming, hot water, steaming and hot air. Mechanical methods include brushing, sweeping, hand hoeing and harrowing gravel surfaces. Integrated weed control uses minimal herbicide application by targetting it more precisely in combination with other non-herbicide management systems. European legislations (Regulation of Plant Protective Products 94/414EE, the Sustainable Use of Pesticides and the Water Framework Directives) are restricting the range of herbicides that are permitted for use on hard surfaces. Currently, weed control on hard surfaces in the UK is dependent mainly on the widespread use of glyphosate with little experience of alternative strategies. This contrasts strongly with the situation in the Netherlands, Denmark and Sweden and to some extent Germany, where national or regional regulations greatly restrict herbicide use. As a result, technologies and experience have been built up on minimising or eliminating the use on herbicide on hard surfaces in these countries which is not replicated in the UK.

The specific project objectives are as follows:

(1) To develop tender specifications and implement non-herbicide and integrated herbicide control and improve management plans, monitor implementation
The aim of this objective will be to define and implement the weed management treatments permitted for use in the project. These will include: (1) Current standard herbicide use; (2) Non-herbicide (thermal and mechanical methods only) use; (3) Integrated management (restricted herbicide application). Three appropriate and comparable adjacent districts in Kent will be identified and characterised and one treatment applied to each district. Landscape quality specifications and standards with respect to acceptable levels of weed infestation will be developed. Contract specifications that include detailed requirements in regard of treatment to be used in each zone and data required from the contractor will be developed. This will incorporate pesticide record sheets, weather conditions at application and amount of weed present etc. Photographic records will be kept of the application areas and the implementation of the treatments. A stakeholder forum will be formed with district and parish council representatives to give feed back on the quality and acceptability of the different weed control methods. Regular feedback will also be sought from the contractor on their perception of the different regimes and issues arising.
(2) Monitor weed growth
The aim of this objective is determine the impact of the different weed control treatments on the prevalence of weeds on different types of urban areas and different surfaces. Fixed recording points each randomly selected in town centre, residential and industrial locations in each of the three districts will be located, marked and set up. The sampling points will be characterised in each location. Weed assessments of species present and infested area will be made on approximately a monthly basis from March until November and repeated each year of the project. Comprehensive photographic records will be kept of the subsequent weed growth.
(3) Determine herbicide losses to the wider environment
Analysis for glyphosate in water will be performed on replicated samples in drianage water adjacent to herbicide application areas following subsequent rainfall events. The differences in emissions between the weed control treatments will be compared and related to rainfall.
(4) Determine economic and environmental cost benefit analysis
The costs of each weed management system will be compared on a like for like basis at the tender – contractor level. This will be set by controlling weeds to the same standard in each treatment. Costs will be broken down into constituent components, including those involved in application fuel, chemicals, labour, monitoring etc. and will be calculated on per m2 for specific levels of weed growth.
(5) Develop and demonstrate guidelines for non-chemical control/ integrated control.
Regular interaction between the project management group and the local stakeholder group will ensure the research remains relevant to the industries needs and the public’s satisfaction. The results from objectives 1-4 will provide the basis for guidelines based on the data and real experience gained in the project. In addition, workshops and demonstrations throughout will be used to disseminate results and advice.
1. To develop tender specifications for non herbicide and integrated herbicide control and improve management plans, monitor implementation
2. Measure weed growth
3. Determine herbicide losses to the wider environment
4. Determine economic and environmental cost benefit analysis
5. Develop and demonstrate guidelines for non-chemical control/ integrated control
Project Documents
• EVID4 - Final project report : PS2802 - Final report   (840k)
Time-Scale and Cost
From: 2009

To: 2015

Cost: £562,594
Contractor / Funded Organisations
East Malling Research
Behaviour change              
Development of tools - facilitate behaviour change              
Environmental Impacts              
Herbicide use              
Monitoring and evaluation              
Pest and Weed Control              
Pesticide use              
Plants and Animals              
Techniques & methodolgies for waste management              
Technology Transfer              
Weed Control              
Fields of Study
Pesticide Safety