Crop Crack: Time to get cleaning ahead of harvest

Bear in mind that no insect pests of grain come in from the field – they are all in the store or on associated machinery just waiting for the grain to arrive. Pests such as grain weevils, saw-tooth grain beetles and mites survive on spilled grain which can be found in crevices, ledges, roof trusses, pits, ducts and augers.

Successful control requires an integrated approach that includes good store hygiene, monitoring for any pest activity and, if necessary, then, applications of pesticide.

A good store hygiene plan

Store cleaning is crucial and should be done as early as possible – ideally at least two months before crop storage is required. It’s important to remember that even empty stores can be at risk of infestation, and particularly if there is grain left from a previous crop. The store should be swept and vacuumed to remove all loose fragments and previous crop that could shelter pests. As well as cleaning the obvious areas, farmers should be sure to check and clean awkward and inaccessible places, including roof spaces and ventilation ducts, tops of dividing walls, grain driers and grain handling equipment.

Pest monitoring

Once the store has been cleaned, it is advisable to check for the presence of insect pests using pheromone traps. These should be placed strategically around the grain store, and if insect pests are detected, then the store should be treated with an insecticide.

Treatment

Where an application of insecticide to the structure of the store is required, options are fewer than previous years K-OBIOL EC25, a pyrethroid insecticide, is now one of the very few products approved for spraying the fabric of the store and handling machinery.

K-OBIOL EC25 is an insecticide containing deltamethrin for treating both the fabric of buildings and for application directly to infested grain, for the control of crawling insects such as grain weevils, saw-toothed grain beetles and grain borers. As well as providing a quick knockdown of grain storage pests on application, it continues to control insect pests that come into contact with the treated surfaces for up to two months after application. There is no waiting period between treatment and use of the store and equipment. However, for maximum efficacy, treatment should be applied 3 to 4 weeks before filling the store to target pests at every stage.

Pre-Harvest Desiccation

The timely use of glyphosate pre-harvest will lower the moisture content of both straw and grain by speeding on the ripening of all green material – secondary tillers, weed-grasses and any broad-leaved weeds that otherwise would remain green and retain moisture in both straw and grain after cutting if not desiccated. Lowering grain and straw moisture levels improves the speed of combining, making for a more efficient threshing and the straw collected more quickly, and will also reduce drying times and costs.