Canola Harvesting BY Derek Thoms

What can be used to harvest canola This is a grain head which is used to harvest small grain products like canola. This would attach to a combine.

This is what we call a combine. This is what a grain head would attach to. Combines are used to separate small grain products like canola from their stalks. Combine

Combining canola Canola is not a difficult crop to harvest. Canola is ready to combine when the seed moisture has dropped to under 10%. Under normal conditions this is about 5-10 days after swathing. Cylinder speed should be about 650 to 700 rpm for small diameter cylinders, and rpm for large diameter cylinders.

Making combine adjustments for harvesting canola Excessive cylinder speed causes seed cracking, skinning and excessive smashing of pods and stems, which may then be difficult to remove from the seed. If the speed is too slow it reduces the capacity of the combine. Slow the cylinder speed to where the amount of cracked seeds is just acceptable

Combining adjustments Stems and pods should be broken no more than necessary and unthreshed pods kept to a minimum. This will reduce overloading the sieves and allow seed separation without excessive over load on the return conveyor. The concave should be open mm in the front and it should range from 3-13 in the back.

Combine Adjustments Wind is controlled by shutters these should be less than half open. If the fan speed is too high then it will blow the canola seeds out with the chaff allowing large amounts of pods in the return. Start with a lower fan speed and gradually increase it until separation of chaff and seed occurs with no seeds being blown over the chaff sieve.

Combine Adjustments Proper adjustment of fan and sieves for the cleaning action is important since canola seeds are light and can easily be blown out of the combine or remain mixed with the chaff. The top sieve or chaffer should be opened enough for good separation 1/4 to 1/3 open. This will keep the seeds from going over the top and out the back of the combine.

Grain loss If the sieve opening is too narrow and coupled with insufficient wind then it can result in high seed losses. The lower sieve should be adjusted depending on the sample seed quality in the grain tank. If too much residue is present in the tank, the sieves are likely too open. If the sample is overly clean, canola seed may be going back to the return conveyor so that the sieves should be opened slightly.

Grain loss A lower sieve setting at 3-6 mm will usually be sufficient. Excessive returns result in seed crackage and the overloading of one section of the combine with resultant high seed losses A loss of 1 lb/acre is equal to 2 seeds of B. napus and 4 seeds of B. rapa per square foot remaining in the field. Average canola harvesting losses in the field are 50 to 100 lb/acre. A standard grain monitor, suitably adjusted, is satisfactory for canola seed

Grain loss A loss monitor can warn of changes in the grain loss rate but it does not accurately measure the amount of loss. The loss monitor will indicate relative changes in loss rate. An increase in the meter reading is a signal to reduce the feed rate by slowing down. The loss monitor will indicate when combine adjustments are necessary.

Canola Swathing Canola can also be swathed. Swathing canola at the optimum stage of ripening reduces green seed problems and seed shatter losses and ensures the quality required for top grades and prices.

Canola Swathing Canola crops can be swathed by most self-propelled or power-take-off driven windrowers. A belt style of windrower is superior to the auger style in reducing crop damage.

Swathing Canola The swath must flow smoothly through the swather without bunching. Bunching leads to uneven drying and combining problems as well as development of diseases like white stem rot under wet or humid weather conditions Canola crops do not often lodge so badly that a conventional swather with a reel will not handle them, but in difficult conditions, a pickup reel set well forward, will help.

Swathing Canola Swathing at the right stage will reduce shattering compared to late swathing, and reduce green seed content and increase seed size/oil content compared to early swathing. When the seeds reach 35 to 40 % moisture they turn from green to light yellow, reddish brown, or brown, then the canola is ready to be swathed.

Storage Bins

Storage If the storage bin is not equipped with an aeration system, the moisture content should be 8.5% or lower. If the canola temperature is above 77 Degrees F when placed into storage, the moisture content should be below 8%. In storages equipped with aeration systems, canola can be stored safely at 9% moisture, if the temperature is reduced as soon as outside air conditions permit. Winter storage temperature should be 41 Degrees F or lower.

Storage Very tight truck boxes and storage bins are required. The seed can sweat for up to six weeks after harvest. So heating and spoilage can occur even at 9-10 percent moisture levels. Canola as low as 8 1/2 percent moisture should be examined for heating at regular intervals. If harvested at high moisture, natural air drying or artificial drying can be used. To maintain seed quality, a drying temperature of 110 F is maximum for commercial production.