By Ronnie Dauber, Garden Guides Contributor Wild Mustard is an
aggressive annual weed that is ingenious to Europe, Asia and North
Africa, and has now become common in the northern part of North
America, namely Canada. It is found in cultivated fields, gardens,
pastures, river banks, roadsides and waste places in Ontario,
creating a serious problem in potential yield and seed quality of
harvested crops. Wild Mustard weeds are responsible for a large
percentage of crop losses because it overpowers the crops and
destroys them. It can also become fatal to cattle when it is mixed
in with the pasture greens and digested in large quantities. As
well, it is a popular host to many pests, insects, fungi and
viruses that cause severe damage to cultivated crops.
General Characteristics
Wild Mustard ranges in height from 30 to 100cm, and can have either
single or multi-branched stems which are greenish/purple. Bright
yellow flowers about 1.5cm wide grow in clusters at the end of each
branch, elongating as the seedpods develop. Each plant produces
about 10 to 18 seeds per pod, and about 2,000 to 3,500 seeds per
plant. The seeds are distributed when the intended crops are
harvested and the seeds are strewn into the ground and spread to
other fields by harvesting machinery. The seeds can remain viable
in the soil for up to 60 years because they are buried deep when
the ground is cultivated and can come forward and germinate any
time.
Growing Conditions
Wild Mustard grows well in almost any soil and prefers full
sunlight, although, it can grow well in partial shade.
Cultivation and Care
Wild Mustard is spread when regular crops are cultivated since its
crop of Wild Mustard seeds is harvested in the fall when the
regular crops are harvested. The care and maintenance given to the
regular crops like wheat or barley, encourage this plant to grow
well.
Weed Control Techniques
The most successful technique in controlling Wild Mustard is to use
regular applications of herbicides. However, Wild Mustard plants
are now adapting to many of these herbicides and have become
resistant to them. As well, since the seeds can germinate over a
long period of time, it is not plausible to allow one field grow
only Wild Mustard so that chemicals can be sprayed on to eliminate
it, since this process will only remove those plants from those
seeds, leaving many more years of supply still in the ground. There
are many kinds of chemicals that can be used to get rid of Wild
Mustard, and many doses and applications depending on the degree of
the infestation. It is suggested that people wanting the proper
technique should contact the Ontario Ministry of Agriculture and
Food Publication 75, Guide to Weed Control.
