Thrips

Thrips damage to roses.




 

Q: I have a problem on my Mr. Lincoln rose bush. When the buds form and before they open, something either stings or bites the bud and it will not open or form properly. I have sprayed the bush with Apple cider vinegar solution, with garlic/pepper tea solution. The bush is located in a new raised bed prepared per your directions for raised beds. I hope the attached pictures can give you an indication of the problem. —Gene Thompson

A: Could be thrips. Drench the soil with Garrett Juice and garlic. Next Year apply beneficial nematodes too the soil at leaf emergence.

Common Name: Thrips

Scientific name: Order Thysanoptera, family Thripidae. Onion thrips—Thrips tabaci. Western Flower Thrips—Frankliniella occidentalis.

Size: Adult—less than 1/25"

Identification: Barely visible, slender, fast-moving insects that range from pale yellow to black. Narrow, fringed wings. Nymphs are light green to yellow.

Biology and Life Cycle: Adults overwinter in plant debris or in bark. Females lay eggs in the spring that hatch in three to five days. Nymphs feed for one to three weeks, then molt to adult stage. Many generations a season.

Habitat: Most gardens. Vegetables, flowers, fruit and shade trees. Causes leaves to crinkle, especially on beans.

Feeding Habits: Adults and nymphs rasp and suck the juice from plant cells and cause silvery speckles or streaks on leaves. Flowers turn brown on the edges and don't open properly. Thrips will attack many different kinds of plants.

Economic Importance: Causes reduced plant production and ruins flowers. A serious onion pest. Damage can cause decrease in bulb size. Spreads viruses.

Natural Control: Bigeyed bugs are the most important natural control, along with minute pirate bugs, lacewings, and lady beetles. Heavy rainfall also helps. Nematodes applied in water drenches will control species that pupate in the soil.

Organic Control: Spray with plant oil or neem products when necessary or release predatory mites or pirate bugs. Garlic tea and seaweed sprays are very effective. Cover plants with row cover material.

Insight: Will bite humans. Bite is similar to chigger bite and may cause a rash. Thrips do have one good point. Some species will eat spider mites.

Thrips damage on Ficus benjamina.

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