Thrips are most active in the spring and become evident in strawberries at this time, especially once surrounding weeds have dried off. In the extreme conditions of summer and winter, thrips are less active and are usually found on alternative hosts. Some thrips activity may also be seen in autumn when mild conditions return. High numbers of thrips can cause cat-facing, a type of malformed fruit. Serious damage to the crop occurs only when there are more than 10 thrips per flower.
Monitoring helps to identify when thrips are building up and whether it is necessary to spray.
Avoid the excessive use of insecticides as western flower thrips rapidly develop resistance. Unfortunately, there are very few insecticides effective against WFT that may be used on strawberries. Growers should use insecticides carefully or seek advice from Agriculture Western Australia. Do not take WFT infested material onto properties as this has been one of the main means of infestation. They usually appear in flat weeds, such as capeweed and Portulaca , before they are found in the strawberry crop.