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Weed identification

This guide is to help you identify the weeds in your crop. Knowing the weed is the starting point for herbicide selection. Often the identification needs to be made, and herbicide applied, at an early stage if effective control is to be achieved.
Common NameScientific Name
Annual meadow grassPoa Annua
Charlock/Wild mustardSinapis Arvensis
Chickweed - commonStellaria media
Chickweed - mouse earedCerastium fontanum
Cleavers/goosegrass/stickty willieGalium aparine
Fat henChenopodium album
Field pansyViola avensis
FumitoryFumaria officinalis
GroundselSenecico vulgaris
Hairy BittercressCardimine hirsuta
Hemp nettle / DaynettleGaleopsis tetrahit
KnotgrassPolygonium aviculare
Rayless mayweed / Pineapple weedMatricaria matricarioides
OracheAtriplex patula
RedshankPolygonum persicaria
Shepherds purseCapsella bursa-pastoris

Charlock/ Wild mustard

Charlock is an annual weed and although preferring a chalky soil will grow on all soil types. Its cotyledons are kidney shaped. Its seeds can remain dormant in the ground for many years. It has an extensive root system so competes strongly with the crop for nutrients. The main germination period is February - April although a low level of germination can occur most months in the year

Chickweed - common

Chickweed is a commonly occurring annual weed. The seedling has light green oval leaves and will grow on all soils. It grows very quickly with a prostrate matted habit choking plants as it spreads over them. It has two main germination periods March - May and September to November.
chickweed        chickweed

Cleavers/goosegrass/ sticky Willie

This is a common and troublesome annual weed . The leav widths a rising in whorls around a square stem. The plants is covered in sticky hairs. It can seriously hinder harvesting in crops due to its straggly habit of growth. Cleavers mainly germinate over a long period in the autumn and winter October - February/March
goosegrass

Fat hen

This annual weed grows particularly well in rich soils. The cotyledons have a silvery appearance while the true leaves are broad with toothed margins. It is an erect ;plant producing small green flowers. It produces a great quantity of seed and removes a lot of nutrients from the soil. Main germination takes place from March - September.

Field pansy

This is a common weed in cultivated areas preferring acid or neutral soils. Its flower is a small scale version of the garden pansy.

Fumitory

This annual has very long strap like cotyledons. Stems are pinkish with leaves divided into leaflets giving the plant a feathery appearance. Its main germination period is February – April with a lesser period from August -October.
fumitory

Groundsel

This common weed has narrow cotyledons and step-like teeth on the first true leaves. It has an upright habit of growth with small yellow flowers. It has two main germination periods March to May and September to November.
groundsel

Hairy Bittercress

A native annual of bare ground growing to a height of 20cm. It flowers from March to August producing narrow seed pods which explode to release seeds.
hairy bittercress

Hemp nettle/day nettle

The cotyledons are oval to round The leaves are toothed and hairy with veins clearly showing and borne on squarish stems. Flowers are purple. Main germination period is February - May.
nettle

Knotgrass

The cotyledons and leaves are long and narrow. The plant has a prostrate wiry growth habit. It is a troublesome weed forming a dense mat which can cause problems when harvesting.
Main germination period February - May

Rayless mayweed/ Pineapple weed

Cotyledons are small and the first true leaves are narrow with few lobes. Later leaves are very finely divided. The plant makes an upright bushy habit with flowers consisting of yellow domes. It is common where trampling or treading takes place such as gateways and on waste ground. While main germination period is March –May this weed can germinate well from February through to November
mayweed

Orache

The cotyledons and first leaves are mealy. The true leaves are long and narrow and the plant generally has a prostrate habit. The seeds can remain viable in the soil for many years. The main germination period is from March to May.
orache

Redshank

The cotyledons are borne on a red stem The first leaves are tinged with red and later leaves are broad. narrowing to a point. The plant has an upright habit and has small spikes of pink seed like flowers. It prefers damp soils. Main germination period March - June
redshank

Shepherd's Purse

While the first leaves are oval later leaves are deeply lobed. The plant is upright with small white flowers and the seed pods are borne along the whole length of the flowering stems. The plant grows very rapidly and seeds profusely. Although main germination is February - May it will also germinate well through to October.
shepherds purse

Speedwell

A common arable weed with main germination periods in February – May and again from September to November
speedwell

Annual meadow grass

A compact tufted grass pale green in colour. Due to its ability to flower and set seed throughout most of the year it is a widespread weed in arable situations. Seedlings become quickly established in open ground. It will grow in all soil types.
meadow grass

Willowherb

The broad leaved willowherb is the most common small flowered willowherb growing to about 50cms.
It flowers from June to September.
willowherb        willowherb