IWM involves using numerous weed control methods to try and manage a weed problem sustainably.

Whilst herbicides can still be used as part of an IWM approach, a major aim is to reduce reliance on them by also incorporating methods including, cultural, mechanical, biological, thermal and genetic control. A combination of such approaches can allow for optimal control of a specific weed problem.

Related topics on FarmPEP include herbicides and herbicide resistance. You can also view the topic pages on grass weeds and broad-leaved weeds which provide examples of suitable control methods.

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This guidance provides instructions on how to gather IPMNET in-field observation data. By collecting observations in a consistent way, you will be able to make meaningful comparisons within and between fields across the IPM network.   Download the guidance at the bottom of this page to find out more!                          Please click here to share pest and disease information about your field(s).

Herbicide resistance is the inherited ability of a weed to survive a rate of herbicide which would be lethal to a member of the normal population. It can develop over time based on repeated selection pressure imposed on the weed. This selection pressure changes the population from susceptible to resistant. Herbicide resistance is becoming an increasing problem in UK agriculture, in both grass weeds and broad-leaf weeds. See also the general topic on herbicides.

'Integrated Weed Management (IWM) systems in the agroecology context; new challenges.' NIAB, Cambridge, UK 24th - 26th of May 2023

Herbicides are substances (usually chemical) used to control weeds in a variety of situations including agriculture, horticulture and managed landscapes. Herbicides are classified according to their mode of action (MOA) - this is the precise biochemical mechanism in which the herbicide targets and kills the weed. The 'active ingredient' of the herbicide is the specific herbicidal compound that has the phytotoxic effect and this is formulated with a variety of other ingredients (including other active substances, surfactants, buffers, adjuvants e.t.c) to make a final product which is given a trade name by the herbicide manufacturer. With any herbicide product you will find an associated product label which explains how to use the product safely and legally. This page provides an overview of herbicides including how they are classified and used. Please link any pages or projects relating to herbicide use to this topic page.  Some widely used herbicides (e.g glyphosate) also have their own topic page. Other related topics on FarmPEP include herbicide resistance,  bioherbicides, broad leaved weeds and grass weeds.  

Broad-leaved weeds are a varied group of weeds that can grow and cause significant problems in arable fields in the UK. Some of the most common broad-leaved weeds in the UK include: Common Chickweed (Stellaria media) , Scentless Mayweed (Tripleurospermum inodorum), Common poppy (Papaver rhoeas), Charlock (Sinapis arvensis L.), Fat-hen (Chenopodium album L.), Common groundsel (Senecio vulgaris), Docks (Rumex spp) and Creeping thistle (Cirsium arvense). See also related topics of: grass-weeds, herbicides, herbicide resistance and integrated weed management.

Grass weeds are a major challenge in UK agriculture and are often highly competitive in arable crops. Some of the most common grass weeds in the UK include: Black-grass (Alopecurus myosuroides), Italian rye-grass (Lolium multiflorum), Brome (Bromus sp.), wild-oats (Avena sp.), Couch grass (Elytrigia repens), annual meadow grass (Poa annua) and Rat's-tail Fescue (Vulpia myuros). You can find specific topic pages for black-grass and brome. See also related topics of: broad-leaved weeds, herbicides, herbicide resistance and integrated weed management

The herbicide glyphosate was first registered in 1974 under the original trade name RoundUp (Monsanto) and has since become one of the most commonly used herbicides globally. It is a non-selective, post-emergent herbicide with a wide range of uses including arable, forestry, and horticulture.

Crop modelling is a useful tool in agriculture to improve our understanding how a crop grows in interaction with all external factors, including environmental interactions and the crop management practices in place. The idea is that by modelling cropping system factors as a mathematical representation, and incorporating real past data to 'calibrate' the model,  you can then simulate various scenarios and predict the impacts of certain changes on crop growth. One example of this would be a simulation of predicted environmental conditions under various climate scenarios to predict the impacts of climate change on crop growth and yields. Whilst models are oversimplifications of reality and can never capture all the complexity of agricultural systems, modelling has been a vital tool underpinning key agricultural developments and models are constantly being developed to be more dynamic, complex and sensitive. One particular application of modelling is in weed control. This page highlights the application of modelling in weed management and introduces a case study of a weed model from a DEFRA report.       

A 1998 study commissioned by the Pesticides Safety Directorate to assess the non-target impacts of pesticides on non-target terrestrial plants (NTTP's).  'To conserve and enhance biological diversity within the UK' was a stated aim of of the UK Biodiversity Action Plan (1994). Over 25 years later this is still a vital issue and the UK has stated its commitment to secure a post-2020 Biodiversity Framework as well as developing a 10 point plan for financing biodiversity (UK Government, 2022). However, a threat to plant biodiversity is non-target effects of pesticides - this is when pesticide materials reach areas beyond the target application area and affect the species there. Effects of pesticides on non-target plants can range from lethal (death of the plant) all the way to enhanced growth of these plants. Such varied effects depend on a range of things including the type of pesticide used, the concentration of its active ingredient and the sensitivity and spatial range of affected plants. Importantly, plants are part of complex food and pollination webs and so pesticide effects on plants can have cascading effects on the fauna that rely on them, and vice versa.

We are establishing a network of farms to share knowledge and data on the application and impact of IPM strategies with the aim to better understand the effectiveness of IPM approaches on farm yield and profitability, and support sustainable, productive systems with no pesticide inputs wasted. We’ve had some initial funding from Defra to design the network, and now we are moving into a pilot phase.   

Written By James Clarke - ADAS Research Director

Docks are perennial weeds that compete with forages of nutritional importance for livestock production.

Biofumigation involves incorporating brassicaceous cover crops into the soil.

The IPMWORKS e-learning modules have been prepared based on successful experiences within the project network, including technical aspects of IPM strategies, farm performance or co-innovation and method for farm hub coaching, targeting both farmers and advisers.

A series of case study booklets compiled through the IPM Works project.

Creeping thistle has become an increasing problem especially for organic arable farms with soils of higher organic matter content.

Root structures and genetics give the weed an advantage over wheat and explain field patches.  

Pre-registration sign up: https://forms.office.com/e/D3gRpBrpFg BASIS and NRoSO points have been applied for.  

Multi-species grassland leys in crop rotations can improve soil quality and nutrient efficiency, particularly with legume inclusion, which enhances nitrogen availability and reduces the need for mineral fertilisers. 

This report is a comprehensive literature review of weed control options, on a national and international level, that could benefit UK crop production in horticultural crops, cereals and oilseeds, sugar beet, potatoes, grassland, legumes and maize

Intercropping, sometimes known as polycropping, is the practice of growing two or more plant species simultaneously in the same field. 

This site offers free access to Proceedings from over 50 years of BCPC Conferences and Symposia dating all the way back to 1954; over 100 Technical Reports from the Weed Research Organization; and the WRO Annual Reports which include reports from each research section of the WRO.

Published in 1999, this report forms part of the work associated with the Integrated Farming systems (IFS) project (1992-1998). The aim of the study was to determine whether there is any difference between the riskiness of IFS and conventional systems in terms of spring spraying opportunities and its effects on production and the environment.. Herbicides were chosen as the 'role model'. The study looks at spraying opportunities and requirements at IFS sites (Hampshire, Cambridgeshire x 2, Herefordshire, Yorkshire and Midlothian. It seeks to apply the rotations to 2 different sized farms of 200 and 350 hectares and finally looks at the risk implications of each situation.  

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Simple meta tags.

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A comma-separated list of keywords about the page. This meta tag is used as an indicator in Google News.
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The Open Graph meta tags are used to control how Facebook, Pinterest, LinkedIn and other social networking sites interpret the site's content.

The Facebook Sharing Debugger lets you preview how your content will look when it's shared to Facebook and debug any issues with your Open Graph tags.

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A set of meta tags specially for controlling the summaries displayed when content is shared on Twitter.

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  • Product Card requires the 'description' field, the 'image' field, the 'Label 1' field, the 'Data 1' field, the 'Label 2' field and the 'Data 2' field.
A description that concisely summarizes the content of the page, as appropriate for presentation within a Tweet. Do not re-use the title text as the description, or use this field to describe the general services provided by the website. The string will be truncated, by Twitter, at the word to 200 characters.
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The MIME type for the media contained in the stream URL, as defined by RFC 4337.