What’s worse: wild mustard in canola, canola in organics?

July on the Canadian Prairies is a vision of beauty. A great many fields are ablaze with the golden yellow of canola in full flower. It seems at times that this brilliant colour is the dominant feature of the landscape, so strong is its visual presence.

Of course it’s not all canola out there. Some of those pretty yellow flowers are a similar but less popular cousin: wild mustard.

Let’s consider one hypothetical, but not unlikely situation, where the ocean of yellow is split by a highway. On one side is canola; on the other, wild mustard.

Likely the canola is a genetically modified variety, containing a gene that makes it Roundup Ready. Likely the mustard is flowering above an organically managed crop.

Although the two sides of the road look pretty similar, they are rarely seen in the same light. To many people, the canola brings a smile and the wild mustard a frown. After all, the canola is an important crop. Wild mustard can significantly reduce crop yields. It’s a pretty clear-cut difference, but let’s consider a different perspective.

Wild mustard has a long history on the Prairies. Rumour has it that the Agriculture Canada weed research station in Regina was established to address this weed problem. When 2,4-D was introduced, and just a whiff of the herbicide seemed to be enough to kill wild mustard, many folks felt it was under control.

Of course, there can still be problems. Wild mustard has a variable dormancy and seems to germinate after each spring or summer rain. This makes control temporary in years with many scattered showers.

An organic farmer has a number of pre- and post-emergent tillage options for early emerging wild mustard, but tillage is often not recommended when there is frequent rain. Some organic farmers will clip the wild mustard plants above a short crop to reduce further seed set.

Wild mustard can be competitive in an organic crop and reduce crop yields.

On the other hand, crops such as flax and lentils do little to suppress wild mustard, but they hold their own surprisingly well in organic fields. As well, wild mustard roots secrete an acid that dissolves small amounts of soil phosphorus, which makes it more available to weeds and crop. Some farmers report that yields were higher in phosphorus-depleted soil when the wild mustard was abundant.

How much problem is an organic field of wild mustard likely to present to the neighbour across the highway?

The seed is small and round and likely to bounce. It is likely to be picked up by birds, other animals, people and equipment. Indeed, it can spread to a neighbour’s field.

Chances are good that this neigh-bour was already planning to spray. Most chemical herbicides will kill wild mustard. There has been some herbicide tolerant wild mustard, but there is no selection for it on organic farms. So the additional problem of wild mustard crossing the highway will be minimal.

Now let’s take another look at that canola. Recommended practice used to be to grow canola no more often than one year in four to prevent insect and disease problems. The Canola Council of Canada now recommends that people have “at least one year” between canola crops. This corresponds to a huge increase in canola’s presence on the land and an associated increase in insecticide and fungicide use.

Increased likelihood of spray drift is not the only problem for canola’s neighbours. People growing cole crops (cabbage family vegetables) have a harder time avoiding canola insects. And canola itself is a weed concern.

How likely is canola seed to spread to the organic neighbour across the highway? Canola seed, like wild mustard seed, is small and round, bouncy and easily carried by birds, other animals, people and vehicles.

More importantly, entire swaths of the stuff have been known to lift off and scatter in the wind. It is likely that canola too will spread beyond the originating field.

How much of a problem is that likely to cause? Canola can cause yield loss, but this is certainly not the main problem.

The presence of canola can prevent sales for an organic producer be-cause of the detection of GM genes in the organic crop. Any crop that could not be easily cleaned of canola would have to be abandoned. As well, organic farmers have a good feed market for their screenings, but this would be lost as well.

Most organic farmers are sympathetic to their canola growing neigh-bours. They understand that they feel compelled financially to buy into GM canola. As the courts have determined, straying transgenic seed remains the property of the developing company, which means liability must belong to the breeder rather than the grower.

Of course, both theoretical neigh-bours across the highway should do their due diligence to prevent spread of their yellow crops.

Blaming the organic farmer for a sea of yellow fails to consider the relative risks of wild mustard and canola spread.

Last year was an especially fav-ourable year for wild mustard, given the pattern of the rain that came. But let’s rethink the shame that organic farmers often feel about mustard. Perhaps the mustard flowering period is, as one old time organic farmer used to say, “time to go fishin’” and avoid coffee row. If only the neigh-bours would do the same.

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