Texas Department of Agriculture Website > Regulatory Programs > Plant Quality > Pest and Disease Alerts > Pecan Weevil
Skip to content
Search
(800)-Tell-TDA
835-5832

Pecan Weevil

The pecan weevil, Curculio caryae (Horn), is a dangerous nut pest of pecan found throughout the southern United States and portions of Texas.  The adult is a brownish weevil, about 3/8 inch long.  The female’s snout is as long as its body; while the male’s snout is somewhat shorter.  The larvae are cream colored grubs with reddish heads. When fully grown, larvae reach a length of 3/5 inch. Pecan weevil infestations reduce nut yield at two points in the growing season. In the summer, adult weevils puncture and feed on immature nuts, causing the nuts to abort.  Later in the growing season, females lay their eggs into larger, more mature nuts.  Larvae consume the developing kernel, rending it unfit for human consumption.

Quarantine

CLICK HERE to view TDA's Pecan Weevil Quarantine regulations.

TDA Approved Treatments for In-shell Pecan Nuts

TDA has designated this section to publicize the departmentally approved treatment methods for in-shell pecan nuts.  

The following are TDA approved treatments for in-shell pecan nuts.

1) Cold treatment of in-shell pecan nuts held at a temperature of 0º Fahrenheit (F) for a period of 7 consecutive days OR 12.2º F for a period of 14 consecutive days or longer after the entire lot has reached the desired temperature.

2) Hot water bath treatment of in-shell pecan nuts.  Water shall be maintained at or above 140º F for a minimum of 5 continuous minutes OR 170.6º F for a minimum of 3 continuous minutes. Water must be continually agitated throughout the dipping period. In-shell pecan nuts must be completely immersed. The exposure period shall begin when water has regained the desired temperature following introduction of in-shell pecan nuts. 

Note: Fumigation is not a TDA approved treatment method.  Fumigation has been proven ineffective at 100% elimination of pecan weevil larvae in nuts without exit holes. 

Shipment of In-shell pecan nuts from Quarantined Areas to Free Areas

In accordance with Title 4, Part 1, Chapter 19, Subchapter L, Rule §19.123(c), quarantined articles from quarantined areas are prohibited entry into or through the free areas of Texas, unless they have been treated to eliminate pecan weevil using a TDA approved treatment method.

Due to a lack of treatment facilities in the pecan weevil quarantined area within Texas, TDA is allowing in-shell pecan nuts from quarantined areas in Texas to ship directly to cold treatment facilities in pecan weevil free areas under conditions outlined in a compliance agreement.

You must obtain a TDA compliance agreement to move or receive untreated in-shell pecan nuts from pecan weevil quarantined areas.

Shipments of out-of-state pecans must be treated prior to entering pecan weevil free areas of Texas. Compliance agreements are not available for out-of-state shippers.

Contact: PlantQuality@TexasAgriculture.gov if you wish to obtain a compliance agreement to ship or receive in-shell pecan nuts from quarantined areas.

TDA Approved Facilities to treat in-shell pecan nuts in Quarantined Areas

Please contact the TDA Plant Quality program at PlantQuality@TexasAgriculture.gov or (512) 463-7660.

TDA Approved Facilities in Pecan Weevil Free Areas of Texas authorized to receive untreated in-shell pecan nuts from Quarantined Areas of Texas

Please contact the TDA Plant Quality program at PlantQuality@TexasAgriculture.gov or (512) 463-7660.

Exporting In-shell pecan nuts to Mexico

Export shipments of in-shell pecan nuts must abide by phytosanitary restrictions imposed by the importing country. 
For in-shell pecan nuts produced in Texas, only those produced in Culberson, El Paso, Hudspeth, Jeff Davis, and Presidio counties are allowed entry into Mexico.  In-shell pecan nuts that have been produced outside of those five counties may not enter Mexico.  Additionally, in-shell pecan nuts must be treated prior to entry, or upon entry, into Mexico. A federal phytosanitary certificate may be obtained by contacting the West Texas TDA Regional Office at (806) 799-8555.

For more information, please visit the United States Department of Agriculture (USDA) Plant Health Export webpage by clicking the following link:  USDA Plant Health Export