Clubroot

Clubroot is a serious soil-borne disease of field crops such as canola and mustard but also of vegetable crops such as cabbage, broccoli, cauliflower and many other plants in the Brassicaceae family. Clubroot was declared a pest in the Alberta's Agricultural Pests Act in 2007.

Clubroot is a fungus that can not multiply without a living host. It infects the roots of the plant and as it continues to multiply within the root it causes the root tissues to swell. This leads to the formation of galls which are characteristic of Clubroot. The galls are quickly decayed by soil microbes, leaving millions of resting fungal spores in the soil. These resting spores are extremely long lived, with a half-life of about 4 years, but they can survive in soil for up to 20 years. Severely infected roots of canola cannot transport sufficient water and nutrients to support the plant. Research has shown the percentage of infected plants will result in half of that percentage in yield loss, for example if 20% of the plants are infected there will be a 10% yield loss.

Growers and any land users such as surveyors, seismic operators, recreationalists, etc., need to be vigilant and diligent in removing potentially contaminated soil from equipment prior to leaving fields, to prevent the introduction of Clubroot to clean fields. Equipment coming from Clubroot infected areas should further be disinfected with a 1-2% bleach solution.

Canola rotations should be 1 in 4 to prevent propagation of potentially introduced spores. The extended rotation away from canola must also include diligent control of host species susceptible to Clubroot including volunteer canola and weeds in the Brassicaceae family.

Use direct seeding and other soil conservation practices to reduce erosion. Reducing the amount of tillage will reduce the spread of the spores within the field and to other fields. Resting spores may also readily move in soil transported by wind or water erosion. Avoid the use of straw, hay or green feed, silage and manure from infested or suspicious areas. Clubroot spores may survive through the digestive tracts of livestock.

Please view the control measures specified in the Alberta Clubroot Management Plan, which are the minimum standard that is to be applied in all municipalities across the province. The Mountain View County Clubroot (Plasmodiophora brassicae) Management policy became effective March 26, 2007 and the Procedures state:

1. Random Field inspections throughout the County will be conducted by the Agricultural Fieldman or designated Pest Inspectors appointed by Mountain View County.

2. Inspectors will attempt to notify land owners as a courtesy, but as per the Agricultural Pests Act, notification is not necessary to enter on to private property to conduct inspections.

3. Inspectors will follow procedures set out by the Agricultural Fieldman on proper sampling techniques and protocol for entering upon land. Best Management Practices will be followed to ensure inspections do not become a source of spreading the disease. The Agricultural Fieldman will maintain current Clubroot Inspection Guidelines for staff.

4. Positive identification of Clubroot shall be confirmed by a laboratory test (PCR).

5. When land is verified positive for Clubroot the landowner will be notified in writing with a legal notice under the Province of Alberta Agricultural Pests Act.

6. When an infection is found, the current crop may be harvested, but all residues from the crop shall not be retained for further use or moved off of the property. Future crop residues will be dealt with at the time the notice is issued.

7. The notice will prohibit the growth of host crops during the next 4 crop years. Following 4 non host crop years Canola or other Clubroot susceptible crops may be re-introduced into the rotation.

There are 19 Municipalities in Alberta that have confirmed cases of clubroot. For a map of the Clubroot infested areas please see the Government of Albert Agriculture and Rural Development link for Clubroot Infested Areas in Alberta in 2011. Mountain View County does not have any confirmed or suspected cases of Clubroot but still must remain vigilate in preventing the disease from entering our County.

Mountain View County is trying to protect its canola producers from Clubroot with our Equipment Cleaning Requirements Prior to Municipal Entry policy. This Policy States:

Mountain View County requires that any equipment brought in from outside the County be cleaned and free of soil and debris prior to entry. Pressure washing equipment will be adequate to achieve this in most circumstances. If the equipment is coming from a municipality known to be infected with Clubroot, the equipment should be further disinfected to minimize any potential liability concerns. Equipment moving between projects within the County should be free of soil and debris. Movement within the County only requires hand cleaning to remove loose soil and debris unless specified otherwise by the landowner. If Clubroot is found within our municipality, cleaning requirements for movement within the County may change.

It is important to keep in mind that equipment sanitation serves many purposes. Proper sanitation procedures will assist in preventing the spread of invasive species, Clubroot and other soil borne diseases.

Further information on cleaning equipment can be found on Alberta Agricultures website under the title Best Management Practices for Disinfesting Farm Machinery and Equipment to Prevent the Spread of Clubroot

These Requirements apply to everyone involved in transporting equipment. Including but not limited to, Agriculture, Oil and Gas Industry, Utility companies, Private Contractors and Municipal Equipment.

For more information on management please see the Government of Alberta Agriculture and Rural Development link for Clubroot Disease of Canola and Mustard.