Furrow closing and pressing is critical for optimizing crop establishment. It ensures uniform seed cover and packing in the seed zone while consolidating soil and promoting seed-soil contact and moisture migration. Multiple component devices can combine closing and pressing in a single pass. The selection of closing, pressing or firming devices depends on soil type, moisture, amount of residue, and crop type. Pressing is generally beneficial but too much packing should be avoided, especially in wet soils.

1. Furrow closing & Pressing Key Points: Furrow closing is critical to optimising crop establishment and seed bed characteristics Closing ensures uniform seed cover and optimum packing in the seed zone Complement seeding depth Consolidate soil, promote moisture migration, and seed to soil contact Maintain slot humidity Maintain/replace residue cover (>70%) Shape furrow (capture rainfall) Flotation (compromise) Multiple components with single functions Jack McHugh Contributions from Dr Jack Desbiolles (Ashworth et al., 2010) and Baker et al., (2007) and from Jeff Tullberg (Murray et al., (2006)

2. Multi component furrow closing and pressing devices usefully combine the two process in one pass – optimisation? Seed firming devices – slides or narrow wheels Push seeds into base of furrow – useful in V and U shaped Need sub furrow tillage? Accurate depth & fertiliser separation Stops bounce

3. Multi component furrow closing and pressing devices usefully combine the two process in one pass – optimisation? Furrow closing and pressing wheels – close by gathering or ridging Independent Design and configuration vary amount of : Soil packing Furrow wall crumbling Gathering soil and residue Associated with firming devices (often-not always) Prevent moisture loss Low soil strength above seed

4. Type of closing, pressing or firming device selection factors Soil type and conditions. Cloddiness and moisture status Amount and type of residue Crop type to be planted Considerations Pressing beneficial Only minimal packing required Seed firming prior to filling improves emergence No press wheels in wet soil Closing method important on dbl disc openers under wet conditions (can reopen under drying conditions and expose seed)

5. Furrow pressing technology Single vertical press wheels provided top down furrow packing -. Flat, Wedged or ribbed tyre Furrow centred - well structured and light soil conditions – cheap & used as depth wheels – over consolidation (surface)or under consolidation in dry soils Single centred ribs – pressure above seeds in friable - non sticky soils

6. Single vertical press wheels provided top down furrow packing Twin ribbed and zero pressure tyres – pressure on seed row sides – sticky soils

7. Furrow pressing technology Inclined press wheels - heavier soil types and dbl disc openers Sweep angle – sideways action Staggered – fracturing – less compaction, soil jamming (wet soil), soil contamination Pinch at seed depth – setting critical (depth and pressure) No water channel

8. Furrow pressing technology Finger/spading and closing wheels - removing sidewall compaction, soil cover gathering and limited seed zone consolidation. Twin arrangements medium consolidation Various designs and materials for residue handling and sticky soils Low residue Poly-wet packing