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  4. San Juan CBP Finds Increase of Thrips in Imported Cut Flowers

San Juan CBP Finds Increase of Thrips in Imported Cut Flowers

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SAN JUAN, PUERTO RICO—Insects can find the most inconspicuous places to hide which may lead to significant effects on the local economy.

"As we are almost a month away from the busy Valentine's Day season, CBP wants to caution importers to use appropriate phytosanitary measures to manage the presence of pests," said Marcelino Borges, Director of Field Operations for Puerto Rico and the U.S. Virgin Islands.

For the past several weeks, CBP agriculture specialists in San Juan have documented an increase in the interception of Thrips (species of Thysanoptera) on various shipments of cut flowers; such as Roses, Dianthus, Chrysanthemums and Aster, imported from Colombia.

Common names for thrips include thunderflies, thunderbugs, storm flies, thunderblights, and corn lice. Thrips species feed on a large variety of sources, both plant and vegetables, by puncturing them and sucking up the contents. A large number of thrip species are considered pests, because they feed on developing flowers or vegetables causing discoloration, deformities, and reduced marketability of the crop.

Flower-feeding thrips may be responsible for pollination while feeding, but their most obvious contribution to their ecosystem remains on the damage they can cause during feeding. Flower-feeding thrips are attracted to bright floral colors, especially white, blue, and yellow, and will land on the flowers and attempt to feed. Some flower thrips will "bite" humans wearing clothing with such bright colors, though no species feed on blood. Such biting does not result in any known disease transmission, but skin irritations may occur.

Growers use limited pesticides or biological insecticides to control thrips populations in the field and in greenhouses.

All infested and contaminated shipments with actionable pests or violations are safeguarded and transferred for appropriate re-export and/or destruction under CBP agriculture specialist custody and/or treatment by the U.S. Department of Agriculture Animal and Plant Health Inspection Service/Plant Protection and Quarantine (USDA-APHIS-PPQ).

Invasive species include non-native, alien, or exotic plant pests (such as insects, mollusks, weeds, or pathogens); animal and zoonotic disease pathogens, which can transmit diseases between animals and humans; or other organisms that can cause economic or environmental harm to U.S. agriculture, range, and forest systems if they enter the United States.

While most plant pest introductions occur unintentionally as an end result of increased global travel and trade, acts of biological terrorism which threaten the United States' agricultural and natural resources are a rising fear. Plant pests, weeds, and diseases are all potential agents of bioterrorism.

CBP recommends exporters, importers and producers to be cognizant of the U.S. Phytosanitary measures and packing procedures before shipping/importing their products.

Nonetheless, CBP agriculture specialists safeguard American agriculture by demonstrating careful diligence as they examine imported shipments detecting and preventing entry into the country of plant pests and exotic foreign animal diseases that could harm agricultural resources. They do this with inspection and prevention efforts designed to keep prohibited agricultural items from entering the United States. These items, whether in commercial cargo or as "hitchhikers" with an international airline/vessel passenger or a pedestrian crossing the border, could cause serious damage to America's crops, livestock, and the environment.

Last Modified: February 3, 2021