In the last issue ofGrainews (July/August), I went over the set up and first two years of this clover and winter wheat trial. This article covers the 2007 and 2008 growing seasons and the results of the trial.
After the difficulty of the seeding operation in 2006 coupled with the dry late summer/early fall in 2006, I did not have the greatest expectations for the winter wheat crop. This feeling especially applied to the two clover treatments compared to the chemfallow treatment. It came as a surprise, then, as we went out to get our first look at the crop in the spring of 2007. It looked remarkably good, especially considering the previous year’s conditions.
There was an in-crop herbicide application consisting of the recommended rate of Curtail M applied on June 20th using a water volume of five gallons per acre. The major weeds at this time were Canada thistle, cleavers and dandelion. One of the observations I have made with previous winter wheat trials that I have done is the lack of a requirement for using a wild oat herbicide. This has also been echoed by other winter wheat producers, and is a strong side benefit of growing winter wheat.
Observations made in early May showed that the winter wheat crop seeded into the chemfallow treatment was noticeably taller (by 20 to 30 centimetres) than the winter wheat in either of the two clover treatments. Observations made later in June found that this height difference had disappeared and the crop height was similar between the three treatments. During June and July the winter wheat in the chemfallow treatment was of a later maturity than either of the two clover treatments.
The plot was swathed on September 6 and combined on September 14, 2007. The strips were weighed with a weigh wagon and samples were retained to determine dockage, moisture and grade. The results are given in Table 6.
In 2008 the decision was made to gather soil tests from each of the treatments and replicates. The objective of this was to see if we could detect differences in the soil after three years of management between the chemfallow, red clover and alsike clover treatments. The results are given in Table 7.
In the spring of 2008 prior to seeding canola, a pre-seeding burnoff herbicide consisting of 0.67 litres per acre of Roundup WeatherMax and 200 millilitres per acre of 2,4-D Ester 700 in five gallons of water was applied on May 17. The major weeds noted were dandelion, volunteer canola, fescue, red clover, alsike clover, stinkweed and toadflax. The previous crop was winter wheat.
Seeding occurred on May 22 using a Haybuster 8000 zero-till hoe drill. 5.3 pounds per acre of LBD 4362 with Helix and Redcoat was seeded 0.5 inches deep and placed in a three-inch wide paired row. Soil moisture was considered good. The fertility program consisted of a granular blend that provided 58-26-0-0. The fertilizer was deep-banded 1.5 inches below the paired seed row.
There was an in-crop herbicide application consisting of 0.33 litres per acre of Roundup Transorb High Concentrate applied on June 12 using a water volume of five gallons per acre. The canola was at the two-to three-leaf stage. The major weeds at this time were Canada thistle, volunteer wheat, red clover, alsike clover and dandelion. The chemfallow strips were generally much cleaner with fewer Canada thistle compared to the two clover treatment strips.
There was a second in-crop herbicide application consisting of 0.33 litres per acre Roundup Transorb High Concentrate applied on July 1 using a water volume of five gallons per acre. The canola crop was bolting at this time. The major weeds at this time were field horsetail, volunteer wheat and Canada thistle
Observations made on July 21 found that the canola in the chemfallow strips was very clean with the exception of volunteer RR canola which was much further along in bloom compared to the crop that had been seeded.
The plot was swathed on August 26. There were no visual differences between treatments and there were no problems with the swathing operation. The plot was combined on September 17, 2008. The strips were weighed with a weigh wagon and samples were retained to determine dockage, moisture and grade. The results are given in Table 8.
At the NATCO site in 2008 there were significant differences in the available sulfur level of the three treatments. The chemfallow treatment had more available sulphur than did the red clover and alsike clover treatments. There were no significant differences in available nitrogen, available phosphorus, available potassium, pH, electro-conductivity/salinity, per cent organic matter, recommended available potassium, available potassium and bushel weight of the three treatments.
At the NATCO site in 2008 there were significant differences in the yield of the three treatments. The chemfallow treatment yielded higher than either the red or alsike clover treatments. The red clover treatment yielded higher than the chemfallow treatment. There were no significant differences in moisture, dockage, protein or and bushel weight of the three treatments.
The cumulative economic results are given in Table 9.
At the NATCO site in 2007 there were significant differences in the yield of the three treatments. The chemfallow treatment yielded higher than either the red or alsike clover treatments. There were no significant differences in moisture, dockage, protein or bushel weight of the three treatments.
At the NATCO site in 2006 there were significant differences in available N and available S of the three treatments. The chemfallow contained significantly more available N than either the red or alsike clover treatments. The red clover contained more available S than either the chemfallow or alsike clover and the alsike clover contained more available S than the chemfallow. There were no significant differences in available P, available K, pH, electroconductivity and organic matter of the three treatments.
At the NATCO site in 2005 there was a significant difference between the moisture levels of the three treatments. The chemfallow had a lower moisture content than the red clover; the alsike clover was not significantly different from either the check or red clover treatments. There were no significant differences in yield, dockage and per cent green between the different treatments.
The alsike clover had the highest contribution margin followed by the chemfallow and then followed by the red clover treatment.
We should not be surprised that the crop yield was higher on the chemfallow treatment compared to both clover treatments. There is a period of time required for the clover residue to decompose and for the N it contains to be released. By comparison, the chemfallow treatment experienced significant N production through the mineralization of organic matter. This was documented in the 2006 soil samples that were taken from the individual treatments. What we are interested in learning is whether or not the N released from the clover treatments will be high enough in the subsequent years to offset the advantage that the chemfallow started with so in the end we can answer our question as to which system is better in the long term at economically supplying N to annual crops.
CPCS wishes to extend its thanks to Calvin Yoder, forage seed specialist with Alberta Agriculture, Sandra Burton, manager of the Peace Region Forage Seed Association and Bernie Schoorlemmer for their support and assistance with this project.
GarryRopchanisresearchco-ordinatorfor theCentralPeaceConservationSociety,and, alongwithhissonAidan,operatesagrain farmnearGrimshaw,Alta.Contacthimat [email protected]
THE ZERO TO SIX INCHES COMPOSITE SOIL TEST REVEALED THE FOLLOWING INFORMATION:
Organic Matter 27 lb./ac., deficient
20 lb./ac., deficient
490 lb./ac., optimum
38 lb./ac., marginal
0.29, good 6.3, neutral
Treatment Yield bu./ac.* % Moist.* % Dock.* % Protein*
*MEANS FOLLOWED BY THE SAME LETTER ARE NOT SIGNIFICANTLY DIFFERENT AT P=0.05, FEED WHEAT @ $5.50/BU TABLE 7 SOIL TESTS OF DIFFERENT MANAGEMENT TREATMENTS AFTER THREE YEARS
- MEANS FOLLOWED BY THE SAME LETTER WITHIN EACH RATE AND COLUMN ARE NOT SIGNIFICANTLY DIFFERENT AT P=0.05 TABLE 8 EFFECT OF UNDERSEEDING CLOVER SPECIES ON WINTER WHEAT PRODUCTION, 2008
- MEANS FOLLOWED BY THE SAME LETTER ARE NOT SIGNIFICANTLY DIFFERENT AT P=0.05, #1 CANOLA @ $9.50/BU TABLE 9 ECONOMICS OF TRIAL TO DATE, NATCO SITE, 2005 -2008
Chemfallow Red Clover
Alsike Clover 52.3a 40.4b
41.7b 15.3a 15.7a
15.4a 1.7a 1.8a
1.5a 9.2a 9.3a
Bu Weight lb./bu.*
Chemfallow 27.3a 21.1a 487.7a 41.3a 6.3a 0.29a Red Clover 26.0a 20.3a 481.0a 37.3b 6.3a 0.29a AlsikeClover 28.7a 19.7a 500.7a 35.7b 6.3a 0.29a
N/ac.* P/ac.* K/ac.* S/ac.* pH*
EC* % OM* N/ac.* P/ac.* K/ac.* S/ac.*
9.7a 84.3a 37.7a
Cont. Margin $/ac.
0a 19.0a 19.0a
Treatment Yield bu./ac.* % Moist.* % Dock.* % Green* Bu Weight lb./bu.* Cont. Margin $/ac.
Red Clover Alsike Clover 18.5a
21.4b 22.3c 9.6a
9.3a 9.4a 1.4a
0.9a 1.0a 0.6a
0.5a 0.5a 52.4a
Chemfallow Red Clover
2008 Revenue $/ac.
2007 Revenue $/ ac.
2006 Revenue $/ac.
2005 Revenue $/ac.
Cont. Margin To Date $/ac.