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

Furrow closing & Pressing

Contributions from Dr Jack Desbiolles (Ashworth et al., 2010) and Baker et al., (2007) and from Jeff Tullberg (Murray et al., (2006)

Jack McHugh

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

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

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

Multi component furrow closing and pressing devices usefully

combine the two process in one pass – optimisation?

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

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)

Considerations

Single vertical press wheels provided top down furrow packing -.

Furrow pressing technology

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

Twin ribbed and zero pressure tyres – pressure on seed row sides – sticky soils

Single vertical press wheels provided top down furrow packing

Inclined press wheels - heavier soil types and dbl disc openers

Furrow pressing technology

Sweep angle – sideways actionStaggered – fracturing – less compaction, soil jamming (wet

soil), soil contaminationPinch at seed depth – setting critical (depth and pressure)No water channel

Finger/spading and closing wheels - removing sidewall

compaction, soil cover gathering and limited seed zone

consolidation.

Furrow pressing technology

Twin arrangements medium consolidation

Various designs and materials for residue handling and sticky soils

Poly-wet

Low residue

packing