Original publication: Cuban Laurel Thrips Control in Interior Plantscapes

The Cuban laurel thrips (Gynaikothrips ficorum ) is an occasional, though potentially serious, pest of Ficus in interior plantscapes. Control of this tiny insect can be difficult because of the limited number of products registered for use in interior plantscapes, difficulty in properly timing insecticide applications to prevent damage and difficulty in obtaining adequate spray coverage indoors.  See image below.

Unlike many other thrips species, Cuban laurel thrips has a limited host range. Host plants for this pest include:  Ficus retusa (preferred host), F . microcarpa , F . azillaria , F . aurea , F . benjamina , F . elastica , F . retusa , virburnum, citrus, Eucalyptus , Gliricidia , and orchids.

 

Damage

Adult and nymphal thrips feed on the upper surface of young and expanding leaves, causing reddish feeding scars along leaf midribs. Leaves in the process of unfolding become deformed, tightly curled and folded, appearing crescent- shaped. Damaged leaves may first turn reddish, then dark brown and hard, before dropping from the plants. Besides causing unsightly plant damage, infestations slow plant growth. Occasionally, Cuban laurel thrips also bite people who come into contact with infested plants.

Life Cycle

Female Cuban laurel thrips lay their eggs in large numbers inside leaves which are curled as a result of adult feeding. The resulting offspring can be found within the pocket galls. The life cycle requires about 30-days from egg to egg-laying adult. Adult Cuban laurel thrips are active fliers and disperse rapidly during hot weather.

Management

Non-Chemical Control.   Because Cuban laurel thrips are principally pests of indoor plants, they are most likely brought in with new foliage plants. Be sure to inspect and avoid purchasing infested plant material. Look for the characteristic, crescent-shaped foliage on plants before purchasing and do not introduce new plants into an established interior plantscape until you are sure the infestation has been eradicated.

Potential host plants should be inspected regularly, particularly during growth periods in the spring and fall. If Cuban laurel thrips are detected, treatments should be applied to protect developing foliage. Since this thrips only attacks tender foliage, pruning new growth will eliminate most oviposition sites. The population should die out before additional new plant growth emerges.

Chemical Control.  Chemical treatments should be applied to infested trees while leaves are expanding. Once damage has occurred, the thrips nymphs within their protective leaf homes are difficult to treat with insecticide sprays. Compared to outdoor plants, systemic insecticides are not as readily absorbed by slow-growing indoor plants. This in combination with the difficulty in getting systemic insecticides into infested, dead or dying leaves makes control with systemic insecticides difficult at best. For this reason, management of Cuban laurel thrips must be preventative or with the goal of preventing further spread.

Products which are labeled for control of thrips in interior plantscapes include:

• Azadirachtin (Azatin XL, Ornazin 3% EC )
• Bifenthrin (Talstar Flowable)
• Clarified Hydrophobic Extract of Neem Oil (Triact 70)
• Cyfluthrin (Decathlon 20 WP)
• Imidacloprid (suppression) (Merit 75 WP, Marathon II, 1% G, & 60 WP)
• Potassium Salts of Fatty Acids (M-Pede)

Mention of commercial products is for educational purposes only and does not represent endorsement by Texas Cooperative Extension or The Texas A&M University System. Insecticide label registrations are subject to change, and changes may have occurred since this publication was printed. The pesticide user is always responsible for applying products in accordance with label directions. Always read and carefully follow the instructions on the container label.

Authors

Scott Ludwig¹ and Bastiaan M. Drees ²
Extension Program Specialist-IPM and Professor and Extension Entomologist; The Texas A&M University System