Maize Agronomy 2015 Teagasc UCD Maize Seminars

2015 Tim O’ Donovan &

Dr. Richard Hackett Teagasc

Presentation Topics Maize Production Economics Decisions before sowing Nutrient management Weed management Foliar disease management Housekeeping - SUD

Maize Production Costs € per hectare

NFS 2013*

(n=50) Teagasc

2015$

Fertiliser (incl. slurry/fym)

342 476

Seed 202 185

Crop protection (incl. vat)

117 80

Machinery hire

464 685

• Representative of 60% of Irish maize crops (plastic & open, all systems) • $ Adapted from Teagasc Crop Costs & Returns 2015

Maize is expensive to grow

• ~ €110 / t DM

• Cutting corners can be expensive

• Attention to detail gives best chance

of success

Maize Production Costs

Site

• Ideally south facing ‘warm’ field

• After grass can give wireworm problems

-No effective control

• Are there scutch, thistle or dock problems

• If so, use pre-drilling glyphosate - in time

Plastic or open

• Plastic increases yield (~3 t DM/ha) and quality

• Effect will be greatest in ‘bad’ year

• Plastic reduces risk

Maize nutrition

• Maize fertiliser costs are very high (€476/ha – Teagasc figures 2015)

• Critical – current soil sample (< 3 years old) before drilling

• Nitrates directive allows 20 Kg/ha P in index 4

Teagasc soil samples 2014

Maize nutrition

• Maize fertiliser costs are very high (€476/ha – Teagasc figures 2015)

• Critical – current soil sample (< 3 years old) before drilling

• Maize is very sensitive to lime - ideal pH for maize is 6.8 - 7.0 but it will grow successfully to 6.3

• Trace elements - apply at the 6-8 leaf stage

The Effect of Lime on Soil P Availability

Sheil et al, 2014

Requirements for 6 t/ac DM maize crop

N P K

144 units/ac 32 units/ac 152 units/ac

Fertiliser required will depend on - soil test results - organic manures

Fertiliser Replacement Value Manure

Type Available Nutrients (units)

N P K Value (€€)

Pig slurry (1,000gal) 19 7 20 €25/1,000gal

Cattle Slurry(1,000gal) 6 5 30 €24/1,000gal

Broiler Manure (30% DM) 11 12 24 €30/t

Layer manure (55% DM) 23 11 24 €35/t

SMC (1 tonne) 3 5 17 €13/t

Phosphorus

Maize root growth slow in cold conditions

• Root uptake of P reduced

• Placing P will help overcome this issue

• Not as big an issue under plastic

• Heat increases P availability to roots

• P allowed on index 4 for maize

Pests

Main pests – rooks & slugs Leatherjackets Wireworm Cut-worms

No Gaucho but can order replacement €€€

Weeds Major effect on yield Up to 80 % reduction Rotation is key to pesticide reduction in plastic crops Timing is key to pesticide reduction in open crops

Weed control

• Scutch, docks, thistles • glyphosate pre ploughing if possible

• Many maize herbicides are residual

• Residual products work best on

• fine seedbeds with some moisture after spraying.

• Early control is vital

Plastic crops Uncovered areas can present a difficulty for

residuals particularly if • Soil is cloddy • Dry weather after sowing • Brassicas present

Plastic crops Option 1 All at sowing Wing P/pendimethalin (PDM) + Cadou Star 0.5 - 0.75

kg/ha or Wing P/PDM + Calaris 1 - 1.5 l/ha at sowing. On ‘newish’ ground, Wing P/pendimethalin (PDM) on

its own may suffice. Follow up may be required (only one Calaris per season)

Plastic crops

Option 2 under plastic only at sowing • herbicide under plastic at sowing (eg. PDM, Wing P) • overall follow up after emergence (Calaris 1-1.5 l/ha)

Open crops

• Main choice will be Calaris (4 – 6 leaf stage) at 1.0 – 1.5 l/ha.

• Pre-emergence options are less popular but worked

very well in Teagasc trials. • Difficult weeds such as thistle, scutch, wild oats and

volunteer potatoes will need specialist herbicides such as Accent, Clopyralid, Titus or Fluroxypyr for effective follow-up control.

Foliar Disease No research in Ireland on disease effects Varietal effects seen (NIAB) Extrapolating from UK/Danish research and farmer experience Sprays are prophylactic Need long term trials Sprays need high clearance Will July spray impact in Sept/Oct?

Foliar disease in varieties (KD – 2010)

Eyespot – UK advice (MGA) If possible choose a field not adjacent to fields where maize was

grown last year Plough ensuring all trash is buried, plough by mid February Choose resistant varieties (new score on NIAB list 2015) Apply fungicides as both a protectant at the 10 leaf stage if

temperatures do not reach 28C in July or in the South west of England

If August is wet and cold apply a contact eradicant at end of August Need high clearance sprayer to time correctly

Eyespot – Danish advice DAS

Spray in two situations: Fields with maize as preceding crop and use of non-inversion tillage

Fields with >5-10 per cent affected plants assessed on 2 leaves above and below ear.

Dose recommendation: 0,7 l Opera per ha @ gs 65 (tassling) One treatment mostly sufficient. If early attacks, use 2 x 0,5 l per ha Leave untreated strips in field to evaluate effect Research gave positive result in 9 out of 12 trials Currently evaluating DSS using rel. humidity and monitor crops

SUD - Professional Users Anyone who uses pesticides in the course of their

professional activities – knapsack, boom, etc No exemptions Appropriate sprayer course done Register by 26th November 2015

SUD - Application Equipment All boom sprayers >3m, orchard and blast sprayers,

must be tested at least once by 26 November 2016 • Tested every 5 yrs up to 2020 • Tested every 3 yrs after 2020 • Test done by private company – you make

appointment

What you sprayed – Product, rate, PCS number When you sprayed it – field, date Why you sprayed it – weeds expected, advisors guidence,etc IPM records One sheet per farm per year Only record what practise is on farm

SUD - Records

Thank You