Thrips continue to be present in the day-neutral organic strawberry planting at the West Madison Agricultural Station, with numbers that have been pretty stable in the last several weeks. Thrips tend to move into plantings on early spring wind storms from Southern states and have not caused any significant damage in the day-neutral strawberry planting. However, several reports in early summer have come my attention from June-bearing strawberry growers and I wanted to touch back on them at this time.

First of all it is very important to remember to scout early in the season to detect thrips. To monitor for thrips, it is usually recommended to shake or tap 10 blossoms per site at 10 or more sites per variety in a white bowl or tray. Action thresholds of 2-10 thrips per flower or small berry may warrant a chemical control, depending on your level of tolerance (for more info see previous article on thrips). While this is the standard monitoring method, we have noticed that direct observations of thrips on flowers and leaves reveal many more thrips than the tapping/shaking method. This could help explain why some growers may have missed the early presence of thrips this season. Our research has also shown that red sticky cards can monitor thrips populations better than white or clear sticky cards and sticky cards can also be used to monitor thrips, though no threshold has been established for red sticky cards yet.

Finally, scouting for damage symptoms directly on fruit as soon as fruit is present is very important to insure proper management strategies can be implemented swiftly. For pictures of bronzing or discoloration symptoms and small hard and seedy berries, please refer to this Ohio State University article or see Figure 1 as an example. For more information about mites, tarnished plant bug, or thrips in strawberry, please refer to this previous article.

Happy growing season!

This article was posted in Insects and tagged Christelle Guédot, insects, Strawberries, Thrips.