Not known to transmit any human or animal pathogens.

Not known to vector any pathogens or other associated organisms.

When trapping more than one species of moth, separate traps for different moth species by at least 65 feet.

The trap should be placed at the same height as the rice plants, which is typically 1.5 - 3 ft. above the ground, depending on the size of the plants. Trap height should be adjusted during the growing season as plants grow taller. 

Trap color is up to the State and does not affect trap efficacy.

Attaching lures to traps

IMPORTANT: Do not include lures for other target species in the trap when surveying for this target.

The BHT (butylated hydroxytoluene) in the lure dispenser is added as an anti-oxidant only.

Trapping surveys are the only approved methods for C. suppressalis, but observing signs of infestation may help detect the pest. 

In rice, early instars will cause infested leaf sheaths to develop transparent patches that later turn yellow-brown and dry. Weakened stems and dead hearts are distinct signs of the pest early in the growing season. White heads or empty panicles are other signs for the presence of the stem borer later in the growing season. Egg masses are present at the leaves' base near the leaf sheath, and entry and exit holes are present on the stalks. 

See the CAPS Pest Datasheet for images of damaged host plants.

A Likelihood of Establishment map is available. This survey should only be considered in the states with appropriate weather conditions and suitable hosts for this insect. The map was produced by the SAFARIS Team. SAFARIS is a modeling framework that enables PPQ to quickly respond to emergencies, efficiently survey for pests, and assess potential pest impacts by collecting critical geospatial data and developing predictive models. SAFARIS is developed and maintained by the NC State University, Center for Integrated Pest Management (CIPM) with support from PPQ PPRA.

Survey timing depends on the number of C. suppressalis generations per year, rice plant availability, and environmental conditions.

In tropical regions where rice is grown year round, the pest has 4-6 overlapping generations and trapping can occur at any time. In temperate regions where the pest overwinters as mature larvae, trapping can begin at the start of the growing season (when the day length exceeds 14 hours) and continue until rice is harvested. 

Surveyors should perform trapping surveys. Visual surveys are not an approved method and cannot be used to report negative data, but we are including some visual guidance to help surveyors who may observe larvae or signs of infestation on the plants (see Signs and Site Inspection for guidance).

     Trapping Survey

     Deploy traps inside rice fields or near crop boundaries and surrounding areas where nonpreferred hosts are present.

     Traps should be placed inside the fields. Two or four traps can be placed depending on the field size. Place some traps in the middle of the field and some towards the edge, spacing traps apart by 65-100 ft. 

     Set the traps at the same height as the rice plants and adjust trap height throughout the season as needed.

Survey for C. suppressalis in preferred hosts (rice or wild rice).

In areas adjacent to or near preferred hosts, surveys can target nonpreferred hosts like Zea mays, Triticum aestivum, Saccharum officinarum, Beckmannia syzigachne, Polypogon fugax or other grasses, which serve as overwintering sites.

Visual inspection of plants is optional while deploying or servicing traps. Plants in the middle of a rice field or in areas of the field where rice stems have been visibly dislodged are more likely to be infested. 

Follow the Specimen Submission Guidance for Lepidoptera.

There are screening aids available on the CAPS website for this pest. 

Solis (2006) offers taxonomic keys for species identification (See link in references).

Chilo suppressalis adults and larvae are easily mistaken for other species within the same genus, including the three Chilo species present in the United States: 

• Chilo plejadellus has a scattered distribution throughout the eastern, southern and midwestern United States and southeastern Canada. This species is a minor pest of cultivated and wild rice (Oryza sativa and Zizania spp.) in Texas, Arkansas, Louisiana, Minnesota, Georgia, and northern Florida.
• Chilo erianthalis is a pest of sugarcane and other grasses belonging to the family Poaceae. This species has been reported from Louisiana, Georgia, and Florida.
• Chilo demotellus is a pest reported in smooth cordgrass (Sporobolus alterniflorus) in Florida.

Genitalic dissection by a specialist is required to distinguish the three species present in the United States from C. suppressalis.

Other similar species include:

• Chilo niponella and C. christophi are similar species that are not present in the United States, but they are smaller and have a more distinct pattern on the forewings.
• Outside of the genus Chilo, Diatraea saccharalis is present in North America and looks similar. These two species can be distinguished based on the presence/absence of ocelli. Diatraea saccharalis is prevalent in the tropical and subtropical Americas, extending from Florida to southern Brazil and Uruguay. D. saccharalis attacks rice, sugarcane (Saccharum officinarum), sorghum, Johnson grass, maize and other members of the family Poaceae.

See the CAPS Datasheet and the Chilo Screening aids for images of these easily mistaken species.