The efficacy of some of the most prominent herbicides has dwindled over the past few years, with weeds now appearing in crops that were previously taken out.

Some less well-known weeds are also being increasing seen, such as rat’s-tail fescue, but identifying unfamiliar weeds can prove tricky.

Help is at hand with several smartphone apps offering help. These four apps not only aid identification, but also offer possibilities for control. Each allows most of its features to be used offline, allowing farmers to make the most out of them while in the field.

Bayer Weed Spotter

This is based on the Bayer CropScience weed guide and provides growers with a weed identification app. It has photos of nearly 100 common grass and broad-leaved weeds found in commercial crops, so covers most angles.

Grassweeds can be identified by following a simple question and answer menu identifying different features on the weed.

This could be looking at whether the leaves are rolled or folded in the stem, whether rhizomes or stolons are present or whether auricles (small projections from the base of a leaf) are present. Similarly, broad-leaved weeds can be identified by pinpointing one or more of the following features: cotyledon shape, true leaf shape and flower colour.

Alternatively, users can browse by growth stage, comparing weeds just after emergence or at flowering, or by searching for weeds in the A-Z menu.

BASF Weed ID

Based on The Encyclopaedia of Arable Weeds in association with ADAS, this provides a reference guide to 140 of the major broad-leaved weeds and grassweeds species in the UK.

It contains 1,000 images and a full description of each weed at the different plant growth stages to allow all-year-round identification. Grassweed drawings are also included, distinguishing features often too difficult to see from a photograph.

Users of the app can take a picture of the weed they are trying to identify, which remains as a smaller image on screen while users filter weeds out by choosing characteristics relating to the weed.

Once the selection has been narrowed, growers can swipe through a slideshow of similar weeds to find the correct one. Each weed comes with additional information and also, where appropriate, some information on similar weeds that it could be mistaken for.

The app also contains a “Map My Weed” tool to help pinpoint location of weeds on a Google map; assign name, size of patch and year, so growers can record the worst affected areas of on their farm.

Dow Agro Product Finder and Weed Wizard

This app gives up-to-date information on the company’s product range for cereals and oilseed rape, helping growers and agronomists select the best solution for specific circumstances.

Product information on the app includes weed lists and tank mixes, as well as key facts.

Users are given six main options including, products, the Weed Wizard and tank mixes.

Users are able to select Weed wizard before being invited to select a crop. They are then taken to a scroll-down menu. Simply select one or more weeds and it will reveal product solutions. However, the app only contains the company’s own products.

DuPont SU Sequencer

This app enables farmers and agronomists to choose the most suitable sulfonylurea (SU) herbicide tank-mix or sequence option available to them.

It also gives up-to-date information on the choice of following crops after the use of SU herbicides. Once on the app, it is a fairly straightforward process; however, growers must register first in order to access it.

Users firstly have to select the crop and season of first applied herbicide. So for example “wheat” + “autumn”. Next select the first herbicide. This then needs to be repeated for the second season.

The app will then give you information on the herbicide combination selection, together with following crop information and other notes as appropriate for example “plough before planting”.