Seedy Ripening Problems With Strawberries

Thrips Description

• Although there are four known thrips species that invest strawberry plants, Eastern flower thrips are the most common in the United States. It's an extremely tiny insect that when full grown has a full body length of 1/16 of an inch. Its body is yellow-brown with feathered wings that lay on its back folded long ways. The nymph shares the same body shape as an adult, yet it lacks wings and is orangey white in color.

Destruction

• Thrips infest and eat away at strawberry plants' flower buds usually in the spring soon after blossom set and continue even after blossom drop. They're drawn to blossoms for their nectar and pollen and rarely are found on leaves. Although damage isn't immediately apparent, their vigorous feeding severely deforms flowers and affects their ability to produce quality fruit. Fruit that forms is usually pale red or light orange in color, small in size and has a seedy texture that's similar to rubber.

Detection

• Although thrips invade all strawberry plants, stressed plants are highly vulnerable. Examine strawberry plants every few days in the spring right after buds develop and until fruit set occurs for signs of thrips. Flower pedals invaded by thrips often yellow. Early season strawberries are at a higher risk of infestation because blossom set generally occurs during thrips prime feeding period. Place a piece of thick white paper below a plant and gently agitate it with your hand. If thrips are present, they should drop onto the white paper making them easy to see.

Control

• Chemical control is warranted when more than 10 thrips per flower are present or for crops with a history of infestation. Treat plants as soon as you identify immature berries with symptoms of insect damage in an effort to salvage what's left of your crop. Spray plants with insecticides formulated with thiodan or lannate, both are effective at managing thrips. Apply insecticides to plants in weekly intervals beginning a week or two prior to bud formation and ending four days before harvest.