1. Conservation tillage in the UK
Jim Orson
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2. 0
5
10
15
20
25
30
35
40
45
19
75
Source:
19
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76
19
77
19
78
19
79
19
80
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81
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82
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85
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86
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90
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91
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92
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93
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95
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96
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97
19
98
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99
20
after non-plough tillage
00
20
01
20
02
20
03
20
04
20
05
20
% of winter wheat in England established
06
20
07
20
08

3. Average wheat yields (t/ha)
t/ha
9
8
7
6
5
4
3
2
1
0
05
10
0
5
0
70
5
0
5
9
9
0
7
8
8
20
20
19
19
20
19
19
19
19
USA UK
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4. Min-till does not mean necessarily mean
reduced fuel use for primary cultivation
Cost/ha Total time Typical fuel Fuel cost/ha
consumption
(£) (minutes/ha) (litres/ha) (£ at 52p/litre)
Plough based
Do these comparison take into
£75-113 65-150 30-50 £16-26
account timeliness?
‘TopDown’ type (working If£61-78 speed of operation required
same 45-70 38-54 £20-28
depth 125-150 mm) then ploughing capacity needs to be
‘Carrier’ type increased by24-59 than 45%-110%
£59-64 more 26-28 £14-15
(working depth 50 mm) to be comparable with the ‘TopDown’
‘Bioseeder’ for OSR resulting in ploughing costing around
£32 24 16-18 £8-9
Direct drill
a total of an additional £45-£120/ha
£21-£31 20-30 8-10 £4-5
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5. The annual % control of black-grass plants needed within
the crop to prevent the weed increasing in winter cereals
%
Tine/disc (5cm) 99%
Tine/disc (10cm) 98%
Tine/disc (20cm) 97%
Tine/disc (20cm) + cultural 93%
(50% less heads)
Plough 90%
Plough (20-25cm) + cultural 80%
(50% less heads)
Source: Moss et al., 2010
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6. Comment faire lever les adventices ?
250
plus on travaille superficiellement,
Plantes/m² plus les adventices lèvent facilement
200
Déchaumage 2 cm fin (Horsch SE)
Déchaumage 4 cm + Rappui (Semeflex)
150
Déchaumage 5 cm (Smaragd)
Chaume nu
100
50
0
Repousses de blé Ray Grass Véronique de Perse
1er déchaumage 1er déchaumage 2ème déchaumage
Boigneville, été 2007

7. Black-grass - quicker emergence
from shallow incorporation
low dormancy seed surface sown Low dormancy seed 1cm depth
High dormancy seed surface sown High dormancy seed 1cm depth
Emergence (% seeds planted)
60
50
40
30
20
10
0
ep ep ct ct ct ct ov ov
S S O O O O N N
9- 0- 0 8- 1 6- 2 3- 3 0- 9- 7-
1 3 0 2
Sarah Cook – glasshouse at ADAS Boxworth, sown 4 September 2010
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8. STAR project – Beccles clay,
Suffolk
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9. STAR project – after 5 years
Yield (relative to ploughing = 100) and cumulative net
margin (£/ha)
Rotation
Winter Spring Continuous
Plough 100 (£2463) 100 (£1450) 100 (£1079)
Shallow (10 cm) 93 (£1885) 88 (£1383) 97 (£1046)
Deep (20 cm) 97 (£2563) 95 (1427) 94 (£870)
Average cumulative margin (£/ha)
£2345 £1428 £1088
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10. Soil penetrometer readings - 2011
STAR project - Effect of cultivation
4.0
3.5
3.0
2.5
Megapascals
2.0
1.5
1.0
0.5
0.0
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Depth (inch)
Annual plough Managed approach Shallow tillage Deep tillage
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11. Soils are now over-stressed!?
3
14 fold
2.5 increase
Soil stress 7 fold
(Bar) at 2 increase 12 t
0.4 m
depth 1.5
1
0.5
0
1930 1940 1980 2006 2006
Source – Tim Chamen, based on Koolen et al., 1992
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12. Cultivated soils susceptible to compaction
– even under very dry conditions
Chicksands – autumn 2009
Colworth – autumn 2009
August 2010
August 2010
Tim Chamen – PhD thesis
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13. More than one reason to achieve
sustainable shallow tillage
Energy inputs GHG emissions
GJ/ha (% of total chain) Kg C02eq/ha (% of total chain)
Diesel 4.7 (28%) 356.6 (11%)
N fertiliser 7.5 (46%) 2,528.6 (81%)
P fertiliser 0.7 (4%) A climate 29.1 (1%)
K fertiliser 0.4 (2%) unfriendly 21.0 (1%)
Pesticides 0.6 (4%) technology 10.8 (0.5%)
Seeds 2.5 (16%) 160.4 (5%)
Total 16.0 A climate 3,106
friendly
Source: Rickeard et al., 2004
technology
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14. Sustainable shallow tillage
• Can a virtuous circle be created:
– need to move less soil
– shallow tillage with lighter tractors should result in
higher organic matter content in the disturbed
layer (leading to improved surface soil tilth) and
less soil damage at depth
– but the impact of wheels/tracks need to be
avoided; can improvements in tyres/tracks and/or
precision techniques (controlled traffic) provide a
way forward?
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15. Initially carbon losses are reduced by the introduction of shallow tillage but
after a few years the organic matter formed from crop residues becomes
concentrated in the cultivated layer and so carbon losses not much less
than ploughing
Comparisons of tillage effects are often made on C concentrations in the top 15 cm (or
less). This is not satisfactory as it does not account for differences in soil bulk density and
placement of OM below 15 cm.
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16. Soil amendment research
8.50
8.00
7.50
Yield (t/ha)
7.00
6.50
6.00
5.50
5.00
4.50
4.00
Spring break Spring break + cover crop
- compost + compost No compost Compost
pH 7.5 7.7
N 10.9 13.7
P 24.3 32.7
K 122.0 198.5
Mg 28.5 49.0
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17. Water infiltration – 2011
NFS cultivation study
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18. Strip Tillage
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19. Strip tillage – great for winter
oilseed rape
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20. Not so good for sugar beet
NIAB Innovation Fund
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21. Conclusions
• Shallow tillage is not sustainable on the
majority of UK the arable area
• Will improved ‘soil fertility’ and better
tyre/track technology and/or controlling traffic
and/or strip tillage provide a way forward?
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