Level II Agricultural Business Operations

92% of agricultural land in Northern

Ireland is in grass

Grass is the cheapest feed for dairy

cows

Maximise grass output from every acre

Introduce more productive swards

Earlier grass growth

Increased grass yield

Better response from fertiliser nitrogen

Improved grass digestibility & palatability

Higher grass sugars and improved ensilibility

The sheaths and backs of the leaves are smooth and shiny

Red stem base

Upper surface of leaf is strongly ribbed

High Moderate Low

PRG Meadow foxtail Bent grass

IRG Rough stalked meadow grass

Crested foxtail

Hybrids Smooth stalked meadow grass

Yorkshire fog

Timothy Cocksfoot Annual meadow grass

Meadow fescue Red fescue Couch grass

White clover

Red Clover

Walk a ‘W’ and assess at points how much PRG is in a sward.

If PRG below 70% - then some work to improve sward will be required

If PRG below 50% then reseed needs to be considered

If the percentage of broadleaved weeds is high, then take action

Before improving sward quality consider-

Cleaning sheughs Drainage Compaction Soil fertility pH Fencing Hedges

1. Sward Replacement – destruction of old sward and replacement by reseed (plough)

2. Sward Renovation - introduction of seed into an existing sward with minimum cultivation

3. Sward Rejuvenation - gradual improvement to sward by better management.

Required if % of PRG in sward is low

Most reliable method of replacing a sward

Spring reseed is usually end March to mid May

Autumn reseed between mid July to late August

Spring reseeds often have a heavier weed

burden than late summer reseed

If high % of scutch/bent grasses or weeds like dock/thistles then old sward should be destroyed by Glyphosphate herbicide

Poor seedbed preparation is most common cause of failure

Seedbed to be fine and firm

Consolidate without compacting

Sow 6-12mm deep

Roll to maintain moisture in top layer of soil

Watch out for pests (slugs, frit fly, leatherjackets)

Alternative to conventional method of plough and reseed

Suitable for;1.Stony soils2.Heavy land that takes time to dry out3.Where rapid establishment is required4.Thin swards (silage ground)

Specialist drills/equipment required

Control perennial weeds before over-seeding

Minimise competition from existing sward. Graze hard or cut silage beforehand.

Prepare a shallow tilth by discing and/or harrowing prior to broadcasting or drilling of seed

Conditions need to be good (not too dry or wet)

Graze lightly when grass seedlings are 10cm high. Graze often for short periods thereafter.

Do not allow long intervals between grazings or closing for silage

Identification and correction of poor managementpractices- Poor drainage Poor soil fertility Weeds Under-stocking Poor integration of cutting and grazing Poaching Excessive use of slurry Compaction

After these issues have been addressed consider reseeding/ stitching-in

Sward Replacement with

ploughing

Sward Replacement

without ploughing

Sward Renovation by stitching-in(Over-seeding)

£/acre £/acre £/acreSoil analysis 1 1 1

Spray 23 23Cultivations 67 42 20Seed & sow 98 98 64

Fertiliser - sowing 38 38 38

Lime – 2t + application 51 51 51

Total/acre 278 253 174

Factors to be considered

1.Sward life – short, medium or long term

2.Sward purpose – Grazing or cutting

3.Growth season/area – early, intermediate, late

4.Soil type – dry & light or heavy & wet

Use varieties with similar heading dates and dates which correspond with intended cutting date

Short term leys – use Italian ryegrass Long term leys – perennial ryegrass Clover inclusion of little benefit if intensive

silage system (2-3 cuts) Hybrids and tetraploids to be considered for

high sugar content Consider Timothy on heavier land

Mixture of 3-4 varieties is normal

Do not need to be similar heading date – can include intermediate and late varieties together

Persistence and ground cover are very important to ensure that sward lasts and can withstand poaching or trampling

Clover can have a role to play

Use mostly diploid varieties (more persistent)

Include some Timothy if ground is heavy

Always use from recommended lists

Why include clover?

Improves digestibility and intakes Increased animal performance Higher protein % than grass Increased mineral content of sward Can reduce need to spread chemical N

fertiliser

Weeds cause economic loss in several

ways;

1.Compete with grass for nutrients and light

2.Less area available for grass growth

3.Poorer quality silage

4.All lead to reduced animal performance

3 types of weed;

1.Annual weed – these complete their life cycle in one year from germination (e.g. Redshank)

2.Biennial – complete their life cycle in two years from germination (e.g. Ragwort)

3.Perennial – live year after year and develop strong underground roots (e.g. Docks)

Annual plant

Can be grazed out by cattle or sheep

Herbicides needed if high infestations in silage swards

Annual plant

Common in spring or early summer reseeds

Hard to graze out if becomes established

Spraying necessary if infestation is severe

Biennial plant Develops leaves in first

season Flowers and grows to

maturity in second season Poisonous to livestock (in

silage or dead) Cutting not advised Pulling or spraying best

control

Perennial weed

Can spread by underground roots

Topping can help but not kill

Spraying best way to eradicate

Perennial weed Develop deep tap

roots and can spread quickly

Topping not effective control

Spraying required but often one spray programme not enough

Perennial weed Common in acidic

wet ground with low fertility

Repeated cutting gives some control

Spreading lime and improving fertility helps

Spraying very effective

Take care to ensure adequate:

Drainage and aeration

Soil fertility

Use of organic manures

Weed control

Stocking levels

Assess existing sward

Check for underlying problems

Select improvement method

Select suitable grass seed mixture

Careful management of new sward