I first experienced zero till when I seeded a test plot in 1990 while working as a soil conservation technician for the Applied Research Association in Manning, Alta. Then, in1994, in my first year as research coordinator for the Central Peace Conservation Society (CPCS) at Spirit River, Alta., I was invited to see a demonstration of the use of a stripper header north of Claremont, Alta.
With both of these events, it was apparent within seconds that this was simply a better way to manage annual crop production. While it was a simpler matter for me to adopt zero till in 1992 on my farm, the experience I had with a stripper header never left my mind. Both caused me to rethink how we produce annual crops and the way we approach moisture management.
Traditionally, we harvest cereal crops in Western Canada by either swathing or straight-cutting. The choice depends on a number of factors:
1)How evenly the crop has matured.
2)Presence of green weeds. Weed seeds with high moisture content can cause spoilage once the crop is in storage; swathing will dry down all plant material.
3)Your equipment. A straight-cut header costs money and not every producer is willing, or can afford, to own one.
4)The evolution and adoption of crop desiccation management.
5)Time management/production costs. Swathing adds a step to harvest and as equipment, fuel and labour costs have risen, it’s become harder to justify this separate operation.
Farm equipment is always evolving, and stripper-header combines were first developed to meet a specific harvesting challenge. In the mid 1980s, Keith Shelbourne modified a harvesting header originally developed for harvesting field peas for the canned pea market.
The header operates by the unusual principle of using a rearward rotating drum fitted with rows of fingers that have an outward V shape with the opening constricting after about eight centimeters and ending in a round opening. The V opening directs and centralizes the stems of the crop as the drum rotates. The heads are popped off the stem as the combine moves forward and the drum rotates backward, and then fed into a conventional table auger and into the feeder house of the combine.
Stripper headers can be used for crops such as field peas, wheat, barley, oats, and some grass seed crops.
The process has several advantages:
1)Increased combine capacity. Because no straw is run through the combine, all of the threshing and cleaning capacity can be focused on the grain sample itself. The impact of the stripper header is so forceful that the kernels are knocked completely out of the head, thus minimal non-grain material enters the combine.
2)Moisture retention. The tall straw traps snow over the winter and reduces evaporation during the growing season.
3)Straw spreading. Since the straw remains where the plant grew, straw-spreading efforts are not required.
4)Recovering lodged crops. It may be hard to imagine, but I’ve seen a header operate in a severely lodged wheat crop and perform way beyond expectation.
5)Green seed management. Immature seeds aren’t removed by the stripper header, and this
*means followed by the same letter within each column are not significantly. No. 1 canola at $9/bu., conventional straight combining at $19.30/ac., combining with stripper header at $12.20/ac.
improves quality and reduces the potential for spoilage. This also applies to green weeds as well as their seeds remain on the stems.
Stripper headers have a number of potential disadvantages that producers may wish to consider before purchasing one:
1)Difficult to see your line at night. As the stripper header only removes the head itself, or the kernels from the head, there is not the usual dramatic difference in stubble height when using a conventional straight cut header.
2)Weight of header. A stripper header is about 50 per cent heavier than a conventional straight cut header. This can result in a greater degree of movement when the combine is traveling. As well, care must be exercised when lowering a stripper header as the increased weight can result in the header dropping further or faster than expected. This can put stress on the header hydraulics and frame.
3)Difficult to judge height.
Judging the height of the header both above the ground and above the crop is difficult, although a header height indicator would help eliminate some of the guesswork.
4)Power to operate the rotor. The rotor is a large mass and requires power to spin it up to its operating speed. While less energy is required to thresh and separate the crop, energy is consumed in keeping the header rotor driven at the desired speed.
5)Seeding through tall stubble. Managing the subsequent tall residue is probably the most important issue that farmers will have to contend with, even with the cutting coulter that CPCS’s Haybuster 8000 zero-till hoe drill is equipped with. We’ve successfully seeded through many severe residue situations but we’ve also had an unacceptable number of instances where the drill plugged with straw. Some farmers have bailed the straw after harvest or mowed it, but this reduces the snow trapping benefit from using a stripper header, takes time and adds cost.
6)Excessive spring moisture. If there is a high amount of snow or if it’s slow to melt, there is a very real risk of delayed seeding.
In 2008, a field scale, replicated trial was set up just east of the Brett Young Seed Facility at Rycroft, Alta. (CPCS would like to thank Brett Young for providing the site for this trial.) The purpose of this project was to evaluate the affect of seeding canola into wheat stubble harvested with a stripper header compared to stubble of the height that would result from a swathing or conventional straight cut header.
A randomized complete block plot design with three replicates was used. Two treatments were compared:
a)Stripper header — tall stubble.
b)Mowed— to simulate swathed or conventional stubble height.
The plot area covered three different crop types. It was predominately wheat with two narrow strips, one of canola and one of barley. Barley stubble proved harder to seed into than wheat.
The wheat crop harvested in 2007 was in the 50 to 60 bu./ac. range. There were no problems encountered with the harvesting operation with the stripper header. Approximately two weeks after harvesting, strips were mowed in to the plots with a rotary mower. This allowed us to simulate the stubble height had the wheat crop been either swathed or harvested with a conventional straight cut header.
The seeding occurred on May 30 using a Haybuster 8000 zero-till hoe drill equipped with 10-inch row spacing and laying two, separate seed rows 3 inches apart from each other. BY 4414 RR canola with, the seeding rate was 5.5 lb./ac. at a depth of one-half-inch.
The fertility program consisted of a blend that provided 63-19-0-0 and was deep-banded 1-1/2 inches below the paired seed row.
There were generally no problems encountered with the seeding operation, however the previous cereal crops were harvested using a stripper header that left very tall stubble and, on occasion, the drill would plug. Overall the rate of plugging was deemed to be acceptable. There were no plugging problems encountered with the mowed stubble strips.
Initially, it was hard to evaluate the treatments as the stubble in the stripper header treatments made it very difficult to gauge the growth of the canola crop. However, as the crop approached the five-to six-leaf stage, the germination and establishment of the canola crop in both treatments was considered to be very good. This is especially important given the severe lack of rainfall that this plot site experienced during the growing season. Observations made during the growing season found that there were no distinct visual differences between the stripper header and Mowed treatments.
The center strip of each plot was swathed on September 10 and combined on October 3. Each of the strips was weighed with a weigh wagon and samples were retained to determine per cent dockage, per cent moisture and grade. The results are given in Table 1.
For economic calculations, two main economic factors probably come into play: The difference in cost between the two header types and the difference in the number of acres per hour each header can achieve. While the cost of a stripper header is higher than a conventional header, a combine equipped with a stripper header can harvest more acres per hour than a combine with a conventional straight cut header and, of course, both systems are less expensive than using a swather and combine equipped with a pickup header. For our purposes, we will be using the costs from a PAMI trial entitled “Harvest Systems Model Study RH 1196” which gives the costs for several different harvesting operations performed on wheat as follows.
There were significant differences in the yield of the two treatments. The stripper header treatment had a higher yield than the mowed treatment. There were no significant differences in the per cent dockage, moisture and green seed of the two treatments.
Seeding canola into wheat stubble harvested with a stripper header resulted in a significant yield increase as well as a $45/ac. higher contribution margin.
While there were difficulties in seeding the crop into such tall stubble, the moisture retention capabilities of this stubble played a significant role in boosting crop yields in a year when moisture was a limiting crop yield factor. This is a very simple example of what we are missing out on as producers when we to not maximize the amount of moisture retained for our crops from snow trapping and by reducing evaporation rates during the growing season.
CPCS would like to extend its thanks to the Agricultural Research and Extension Council of Alberta, for supporting this project through the ESAIP funding program.
COST $/AC. 26.00
Conventional Straight Cut
TA BLE 1 EFFECT OF STRIPPER HEADER ON CANOLA PRODUCTION, BRETT YOUNG SITE, 2008 FERTILIZER TREATMENT
HARVEST COST $/AC.
CONTRIBUTION MARGIN $/AC.
Mowed Stubble 35.4a