1. Extra crop competition with weeds by reducing crop row spacing Peter Newman

2. Hi! Thanks for downloading our presentation. There’s additional information for you to use in the notes section below each slide, just be sure to leave all the logos where they are. If you have any questions, please contact Peter Newman, T: 08 9964 1170, E: petern@planfarm.com.au.petern@planfarm.com.au Thank you, The AHRI Communication Team (Peter Newman, Brogan Micallef & Lisa Mayer)

4. 1999 - Mingenew More practical seeding rates & row spacings Increasing competition reduces weed seed set Little benefit in increasing seeding rate above 60 kg/ha Panicles /m 2

5. Glen Riethmuller 27 year trial – stubble retained 27 year long crop row spacing & residue trial (Merredin) Same row spacing is repeated on the same plots Compares stubble burning with full stubble retention Uses pre-emergent herbicides for ryegrass control Introducing a ryetec seed catching system (2004) saw big differences in ryegrass seed set between row spacings

6. Glen Riethmuller 27 year trial – stubble retained The holy grail of crop competition research! 27 years of narrow row spacing & normal herbicide use with full stubble retention has smashed the ryegrass Narrow crop row spacing is a great way to suppress weeds

7. 1% / inch And the best news of all? Narrow row spacing of wheat yields more than wide row spacing! 1% yield decrease for every inch of row spacing wider than 7” (18cm) (CSU survey) The higher yielding the crop, the greater the benefit Narrow row spacing results in more crop, less weeds. It’s better than being free, it makes money!

8. Seeding Efficiency (% of seeds that emerge) Seeding rate (kg/ha) Narrow row spacing is an efficient use of wheat seed Knowing seed size, germination % & seed rate the number of wheat seeds sown was calculated Narrow row spacings at lower seeding rates had higher seeding efficiency Almost 100% of the wheat seed sown at 15cm row spacing at 60 kg/ha emerged compared to only 70% of the seed emerging in the wide row spacing, high seeding rate

9. Benefit compared to 12” 10” (25cm) 7.5” (19cm) Reduction in row spacing (cm)511 Wheat yield benefit (kg/ha)4088 $/ha benefit$10.80$23.76

10. Cost compared to 12” 10” (25cm) 7.5” (19cm) Extra cost of bar (John Deere)$13,000$24,000 Cost /ha/yr (8yr 2000ha)$0.81$1.50 Extra fuel ($/ha)$1.20$3.50 Delayed sowing cost ($/ha)0$5.56 Total extra cost /ha$2.01$10.56

11. Net benefit $/ha 10” (25cm) 7.5” (19cm) Cost$2.01$10.56 Benefit$10.80$23.76 Net Benefit $/ha$8.79$13.20 Wheat – 2 t/ha Yield increase of 8 kg/ha/cm

12. Summary Very cost effective method of weed control Cereal crops sown at narrow row spacing yield more & compete better in most situations Higher percentage of seeds sown emerge at narrow row spacing Can achieve narrower row spacing with modern equipment Not every grower can achieve 7.5” (19cm) row spacing but most growers can achieve narrower than their current row spacing. Food for thought for the next machinery purchase.