Angoumois Grain Moth

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PestControlBasics Editorial Team

Reviewed by Derek Giordano · Updated 2026

Illustrated identification guide — PestControlBasics.com

🔍 Identification

Adults: 8-10mm wingspan; pale golden-yellow with narrow, pointed wings and distinctive pointed hindwing fringe. Larvae (damaging stage): 5mm; white/cream; found inside grain kernels. Exit holes: round, cap-like emergence holes in individual grains. Affects: corn, wheat, rice, barley, and sorghum in storage.

🧬 Biology & Behavior

Females lay eggs on grain in the field or in storage. Larvae bore directly into kernels, feed inside, pupate inside, and adults chew an exit hole. The entire development occurs within a single grain kernel. Multiple generations per year in warm storage. Infestation may be entirely invisible until adult emergence begins.

⚠️ Damage & Health Risk

Hollow, ruined kernels; adult moth emergence from stored grain; grain quality loss; secondary fungal infection in damaged kernels. Can cause complete loss of stored corn.

🔧 DIY Treatment

Freeze at 0°F for 4+ days before storage. Heated air drying of grain reduces moisture and creates inhospitable conditions. Store in sealed airtight containers. Diatomaceous earth at labeled mixing rates in bulk grain. Check grain regularly by floating in water — infested kernels float.

👷 When to Call a Pro

Commercial grain storage: grain protectants, proper bin sanitation, and temperature management are the foundation of integrated grain management.

❓ FAQ

How does this differ from Indian meal moth?

Indian meal moth larvae feed on grain surfaces and produce visible silk webbing throughout the storage container. Angoumois grain moth larvae develop inside individual kernels with no visible webbing — the infestation is completely hidden until adult moths emerge.

What grain is most at risk from Angoumois moth?

Corn is most commonly affected — the moth's original host crop. Wheat and rice are also commonly infested. Infestation often begins in the field before harvest.

Factor	Details
U.S. Range	All or most U.S. states
Regional Detail	Distribution varies — consult your local extension service for regional prevalence data.

Factor

Details

U.S. Range

All or most U.S. states

Regional Detail

Distribution varies — consult your local extension service for regional prevalence data.

📅 Treatment Timing Guide

Treating at the right time dramatically improves results. Pest control timed to the life cycle uses less product and achieves better long-term control.

Period	Action
Spring	Inspection and perimeter treatment before pest season starts.
Summer	Active monitoring and targeted treatments as needed.
Fall	Preventive treatment before overwintering pests seek entry.

Period

Action

Spring

Inspection and perimeter treatment before pest season starts.

Summer

Active monitoring and targeted treatments as needed.

Fall

Preventive treatment before overwintering pests seek entry.

💰 Professional Treatment Costs

Service Type	DIY Cost	Professional Cost
Initial inspection	Free (self-inspect)	$75–$150 (often credited to treatment)
One-time treatment	$30–$100 in materials	$150–$500
Annual service contract	N/A	$400–$900/year
Severe infestation	Often ineffective alone	$500–$2,500+

Service Type

DIY Cost

Professional Cost

Initial inspection

Free (self-inspect)

$75–$150 (often credited to treatment)

One-time treatment

$30–$100 in materials

$150–$500

Annual service contract

N/A

$400–$900/year

Severe infestation

Often ineffective alone

$500–$2,500+

Prices vary by region, property size, and infestation severity.

❓ Common Questions About 🦋 Angoumois Grain Moth

How do I confirm I actually have this pest (not something similar)?

The most reliable confirmation is a physical specimen — capture one and compare to reference images on this page. For cryptic pests (bed bugs, termites), look for secondary signs: frass, shed skins, mud tubes, or bites with a specific pattern. When uncertain, a professional inspection is faster than months of misidentification.

Can I treat this myself or do I need a professional?

DIY is effective for small, accessible infestations caught early. Professionals are worth the cost when: the infestation is inside wall voids or structural elements, multiple rooms are affected, you have health-risk pests (hantavirus, venomous species), or DIY has already failed twice.

How long until the infestation is completely gone?

Expect 3–8 weeks for most infestations with proper treatment. Insects with dormant life stages (pupae, eggs) extend the timeline because those stages are impervious to most insecticides. Follow-up treatments at 2 and 4 weeks catch each new cohort as they emerge.

What's the most common mistake people make treating this pest?

Treating only the visible pest population while ignoring the harborage site, entry point, or breeding location. Killing adults provides temporary relief but the population rebuilds from hidden egg cases, pupae, or new arrivals through unaddressed entry points.

🦋 Angoumois Grain Moth