Evercrop phase II — perennial pastures in cropping
systems
Graeme Sandral
Research Agronomist
Evercrop trial at Field Site
Evercrop is a national project funded by the Grains Research and Development Corporation (GRDC)
and the Future Farming Industries CRC to explore the benefits and fit of perennial pasture plants in
cropping systems.
In pasture:crop rotations, the aim of the pasture phase is to maximise benefits to the livestock and
cropping components of the farm business. To test the merits of different pasture types and
establishment techniques to both cropping and livestock systems, five experiments were established in
2012 through parts of southern NSW at Mirool (471mm average annual rainfall), Lockhart (484mm),
Wagga Wagga (530mm), Eurongily (535mm) and Burrumbuttock (580mm).
The treatments are described in Table 1. Cultivars used include Aurora and Genesis lucerne; Sirolan
phalaris; Casbah biserrula, Angel medic; and a Sub clover mixture of Bindoon, Riverina and
Coolamon. All cultivars of the same species were sown in equal parts by weight.
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Table 1. Treatment descriptions sown in 2012 at five sites
Species and species
Pasture description and sowing rate
combination
Sub clover Monoculture
Sown with Sub clover only (4 kg/ha)
Lucerne Monoculture
Sown with Lucerne only (3 kg/ha)
Lucerne Sub clover Mix
Sown with Lucerne (3 kg/ha) and Sub clover (4 kg/ha) in the same row
Lucerne Sub clover 1:1
Lucerne (3 kg/ha) sown in one row and Sub clover (4 kg/ha) sown in
the other row
Lucerne Biserrula 1:1
Lucerne (3 kg/ha) sown in one row and Biserrula (1kg/ha) sown in the
other row
Lucerne annual Medic
Lucerne (3 kg/ha) sown in one row and annual Medic (3 kg/ha) sown
1:1
in the other row
Lucerne Sub clover 1:2
Lucerne (3 kg/ha) sown in one row and Sub clover (4 kg/ha) sown in
two rows
Phalaris Lucerne Mix Sub Phalaris (1.5 kg/ha), Lucerne (1.5 kg/ha) and Sub clover (4 kg/ha) sown
clover
in every row
Phalaris Lucerne 1:1 Sub
Phalaris (1.5 kg/ha) sown in one row, Lucerne (1.5 kg/ha) sown in the
clover
other row with Sub clover (4 kg/ha) sown in all rows.
Phalaris Lucerne 1:2 Sub
Phalaris (1.5 kg/ha) sown in one row, Lucerne (1.5 kg/ha) sown in the
clover
next two rows with Sub clover (4 kg/ha) sown in all rows.
Phalaris Sub clover 1:1
Phalaris (3 kg/ha) sown in one row and Sub clover (4 kg/ha) sown in
the other row
Phalaris Sub clover Mix
Sown with Phalaris (3 kg/ha) and Sub clover (4 kg/ha) in the same row
2
Field Plan – Wagga Wagga
1
Lucerne_Phalaris50_1:1_Subclover
2
Lucerne_Medic_1:1
3
Lucerne25_Subclover_Mix
4
Phalaris_Subclover_mix
5
Lucerne_Biserrula_1:1
6
Lucerne_Mono
7
Subclover_Mono
8
Lucerne_Phalaris25_Mix_Subclover
9
Lucerne_Biserrula_1:1
10
Phalaris_Subclover_1:1
11
Lucerne_Medic_1:1
12
Lucerne_Phalaris75_2:1_Subclover
13
Lucerne_Mono
14
Lucerne75_Subclover_1:2
15
Lucerne_Phalaris75_2:1_Subclover
16
Lucerne50_Subclover_1:1
17
Phalaris_Subclover_mix
18
Phalaris_Subclover_1:1
19
Lucerne50_Subclover_1:1
20
Subclover_Mono
21
Lucerne_Phalaris75_2:1_Subclover
22
Lucerne_Phalaris25_Mix_Subclover
23
Phalaris_Subclover_1:1
24
Lucerne75_Subclover_1:2
25
Lucerne_Phalaris50_1:1_Subclover
26
Lucerne75_Subclover_1:2
27
Phalaris_Subclover_mix
28
Lucerne_Mono
29
Lucerne25_Subclover_Mix
30
Lucerne50_Subclover_1:1
31
Lucerne_Phalaris25_Mix_Subclover
32
Lucerne25_Subclover_Mix
33
Subclover_Mono
34
Lucerne_Medic_1:1
35
Lucerne_Phalaris50_1:1_Subclover
36
Lucerne_Biserrula_1:1
3
Results
Seedling counts
Table 2. Seedling counts (plants m-2) for perennial species in 2012 and Sub clover,
Biserrula and annual medic in 2012 and 2013.
Perennial Perennial Total
Annual
Lucerne
Phalaris
Perennial legume
Species and combination
2012
2012
density
2012
Sub clover Monoculture
0
0
0
33
Lucerne Monoculture
55
0
55
0
Lucerne Sub clover Mix
45
0
45
31
Lucerne Sub clover 1:1
60
0
60
31
Lucerne Biserrula 1:1
55
3
58
15
Lucerne annual Medic 1:1
60
0
60
38
Lucerne Sub clover 1:2
54
0
54
41
Phalaris Lucerne Mix Sub clover
29
27
56
33
Phalaris Lucerne 1:1 Sub clover
23
23
47
37
Phalaris Lucerne 1:2 Sub clover
25
24
49
39
Phalaris Sub clover 1:1
0
50
50
29
Phalaris Sub clover Mix
0
56
56
39
Average
34
15
49
26
* Annual legumes: Sub clover, Biserrula and annual medic in respective treatments.
Annual
Legume*
2013
281
6
81
121
37
39
128
58
59
97
108
97
93
Considering the perennial species alone, all treatments have the same perennial plant density (Table
2). Across the three annual legume species Biserrula was the only treatment that had significantly
fewer seedlings in the year of establishment. In the first year of regeneration (2013) annual legume
seedling density was lower in Lucerne Biserrula 1:1 and Lucerne annual Medic 1:1 and highest in the
Sub clover Monoculture. Where mixed with perennial species, the highest annual legume seedling
regeneration was in the Lucerne Sub clover 1:2 treatment (Table 2).
Pasture production – 2012
The highest pasture yield in the establishment year was produced by the Phalaris Lucerne 1:1 and 2:1
(with sub clover sown in each row) and Phalaris Sub clover 1:1 treatments (Table 3). Among the pure
legume treatments the highest yields were produced in the Lucerne Sub clover 1:2 and Lucerne
Biserrula 1:1 treatments. Sub clover monoculture had the lowest total dry matter yield while the
Phalaris Sub clover mix produced the lowest legume yields (Table 3).
Commonly the highest yields were achieved where phalaris was a component of the pasture. Only one
treatment (Phalaris Sub clover mix) fell below what is recommended as the minimum legume content
(20%) required for pastures. The treatments where a perennial species (lucerne or phalaris) was sown
in alternate rows at a ratio of 1:1 with an annual tended to out yield comparator treatments in which
the perennial and the annual legume were mixed in the same row. These early results suggest there
may be advantages in sowing perennial and annual species in separate alternate rows (Table 3 – see
2012 data).
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Table 3. Total and legume only peak first year (2012) pasture production (kg/ha) and
percent legume, as well as total and legume only second year (2013) autumn/winter
pasture production (kg/ha) and percent legume.
Species and species
combination
Sub clover Mono
Lucerne Mono
Lucerne Sub clover Mix
Lucerne Sub clover 1:1
Lucerne Biserrula 1:1
Lucerne Medic 1:1
Lucerne Sub clover 1:2
Phalaris Lucerne Mix Sub
clover
Phalaris Lucerne 1:1 Sub
clover
Phalaris Lucerne 1:2 Sub
clover
Phalaris Sub clover 1:1
Phalaris Sub clover Mix
Average
Peak
Total
DM
Peak
Legume
DM
%
Legume
June
Total
DM
June
Legume
DM
June
%
Legume
2012
715
2149
1513
2098
2615
2223
2960
2012
715
2149
1513
2095
2615
2223
2960
2012
100
100
100
100
100
100
100
2013
49
769
781
723
603
642
740
2013
46
707
719
665
507
578
710
2013
94
92
92
92
84
90
96
4488
2009
45
1151
472
41
5323
1636
31
1093
492
45
6087
5064
3505
3228
1400
1177
397
1741
23
23
11
69
861
1158
1378
829
542
255
69
480
63
22
5
68
Autumn/winter 2013 production
Autumn/winter pasture production was highest in treatments that had either phalaris sown as a mix or
phalaris sown in 1:1 alternate rows. Not surprisingly the highest legume yields tended to occur in
those treatments containing lucerne. When the two Phalaris Sub clover treatments were compared, the
1:1 sowing arrangement once again had a higher legume content compared to the ‘mix’ treatment.
The lowest yielding pasture was the Sub clover monoculture (Table 3 – see 2013 data).
Valuing pasture types - Nitrogen:
In the cropping zone pastures contribute to both livestock and cropping components of a farm business
by adding atmospheric nitrogen (N) to the soil. To estimate the value of the N contribution by the
pastures (in N fixed kg/ha) we have assumed 3.5 % N concentration in the legumes and a fixation
efficiency of 80% for the cumulative above ground legume dry matter (kg/ha). The estimated dollar
value of the N was provided by assuming Urea cost was $550/t with an N concentration of 46%, while
the estimated value to crops assumes 50% of the N fixed is utilised by the following crop. The highest
N values were achieved where lucerne was included. The most valuable pasture in terms of N
contribution to cropping (Lucerne Sub clover 1:2) was seven times more valuable than the lowest
valued pasture (Phalaris Sub clover Mix) for N contribution (Table 4). The rankings for N are
expressed as a percentage of the best performing treatment which was Lucerne Sub clover 1:2 (e.g.
100% in Table 4).
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Table 4. Cumulative total dry matter (kg/ha), percent legume, cumulative legume dry
matter (kg/ha), estimated N fixed (kg/ha), N value ($/ha), Value to crop ($/ha) and
ranking of highest to lowest value (%).
Species and species combination
Sub clover Monoculture
Lucerne Monoculture
Lucerne Sub clover Mix
Lucerne Sub clover 1:1
Lucerne Biserrula 1:1
Lucerne annual Medic 1:1
Lucerne Sub clover 1:2
Phalaris Lucerne Mix Sub clover
Phalaris Lucerne 1:1 Sub clover
Phalaris Lucerne 1:2 Sub clover
Phalaris Sub clover 1:1
Phalaris Sub clover Mix
Average
Cumulative
Cumulative
Cumulative
Estimated
Estimated
Estimated
Total DM
% Legume
DM
100
98
97
98
97
98
99
44
33
28
23
10
69
Legume
Kg/ha
761
2856
2232
2760
3122
2801
3670
2481
2128
1942
1432
466
2221
N Fixed
kg/ha
21
80
62
77
87
78
103
69
60
54
40
13
62
Value of
N $/ha
25
96
75
92
104
94
123
83
71
65
48
16
74
Value to
Crop $/ha
13
48
37
46
52
47
61
42
36
32
24
8
37
764
2918
2294
2821
3218
2865
3700
5639
6416
6948
6222
4883
4057
Valuing pasture types – Livestock
An estimate of the value/ranking of each of the treatments on livestock production was calculated
using GrazFeed®. Dry matter available for grazing was calculated by assuming an efficiency of
utilisation of 50% above a minimum amount of 1200 kg/ha of available pasture. The daily intake rate
and growth rates of 30 kg merino wether lambs, were calculated for each of the treatments based on
the legume composition achieved and assuming digestibility of 80 % and 45% for green and dead
pasture respectively. Total weight gain was then calculated based on the dry matter available for
grazing, the daily intake rates and the daily growth rates predicted. Each of the treatments was then
ranked according to estimated weight gain (per ha) revealing that the best lamb production would be
achieved from treatments that contained both phalaris and lucerne (Table 5).
The rankings for livestock performance are expressed as a percentage of the best performing treatment
which was Phalaris Lucerne 1:2 with sub clover sown in every row (e.g. 100% Table 5). Overall rank
considers both the nitrogen contribution and the livestock performance and this indicates that the best
performing treatments were Lucerne Sub clover 1:2, Phalaris Lucerne Mix with Sub clover, Phalaris
Lucerne 1:1 with Sub clover and Phalaris Lucerne 1:2 with Sub clover.
6
Rank
for N
out
of 100
21
78
61
75
85
76
100
68
58
53
39
13
61
Table 5. Cumulative dry matter production, legume content, pasture available (for
grazing), predicted dry matter intake of 30 kg merino wether lambs and calculated
animal production for each pasture treatment assuming 80% digestibility of green
pasture and 45% digestibility of dead pasture. Dry matter available for grazing was
calculated by subtracting the dry matter assumed in each of the scenarios from the
cumulative dry matter production.
Cumulative
Total DM
Species and species combination
Sub clover Mono
764
Lucerne Mono
2918
Lucerne Sub clover Mix
2294
Lucerne Sub clover 1:1
2821
Lucerne Biserrula 1:1
3218
Lucerne Medic 1:1
2865
Lucerne Sub clover 1:2
3700
Phalaris Lucerne Mix Sub
clover
5639
Phalaris Lucerne 1:1 Sub
clover
6416
Phalaris Lucerne 1:2 Sub
clover
6948
Phalaris Sub clover 1:1
6222
Phalaris Sub clover Mix
4883
Average
4057
DM
Grazed
103
153
190
157
237
349
Rank for
livestock
out of
100
28
12
25
35
27
48
1.43
394
79
73
2608
1.42
426
91
75
2874
2511
1842
1578
1.41
1.38
1.55
1.49
365
254
162
254
100
84
56
53
76
62
34
59
kg/ha
Estimated
DM Intake
859
547
811
1009
833
1250
kg/hd
1.54
1.55
1.54
1.55
1.55
1.45
2220
Estimated
wt gain
kg/ha
Overall
Rank
53
37
50
60
52
74
Conclusion
At this early stage an overall ranking which incorporated nitrogen and livestock benefits show that 3
of the top 4 ranked pastures included both lucerne and phalaris. This highlights the potential value of
adding a perennial grass to lucerne/sub clover based pastures. The results also showed that the choice
of sowing method and pasture species together can have a large impact on returns ($/ha). For example,
the Phalaris plus Sub clover 1:1 outperformed the Phalaris plus Sub clover mixture and Lucerne plus
Sub clover 1:1 which also outperformed the Lucerne plus Sub clover mixture. Pastures containing
perennial species also outperformed annual species based pastures (i.e. the Sub clover monoculture).
These are the first year results of an experiment that will continue for a further two years before
treatments will be cropped to measure grain industry benefits.
Report produced by Graeme Sandral, Richard Hayes, Guangdi Li and Jim Virgona - September 2013
7