level ii agricultural business operations. 92% of agricultural land in northern ireland is in grass...
Post on 16-Dec-2015
220 Views
Preview:
TRANSCRIPT
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
top related