Locust vs Grasshopper

📐 FIELD GUIDE ILLUSTRATION

Grasshopper (Acrididae) identification illustration with labeled anatomical features — PestControlBasics.com

Original illustration by PestControlBasics.com. Use the labeled features above to confirm your identification.

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PestControlBasics Editorial Team

Reviewed by Derek Giordano · Updated 2026

🔍 Identification

Garden Grasshoppers: 15-50mm; brown to green; long hind legs; leaping ability. Many species; most are solitary and cause minor garden damage. Migratory Locust: The same species (e.g., S. gregaria) in a different phase — high population density triggers hormonal and behavioral changes, producing swarming, migratory locusts with different body shape and coloration. The US has no true 'locust' species currently — the last Rocky Mountain locust (Melanoplus spretus) went extinct around 1902.

🧬 Biology & Behavior

Common US grasshoppers: differential grasshopper, two-striped grasshopper, red-legged grasshopper. These cause significant crop and garden damage in drought years when populations irrupt. True locust phase-change behavior (solitary to gregarious) is well-studied in Schistocerca and Locusta — triggered by serotonin release when grasshoppers frequently touch each other's hind legs.

⚠️ Damage & Health Risk

Defoliation of garden plants; agricultural crop damage; complete defoliation during population irruptions in drought years.

🔧 DIY Treatment

Row covers for high-value garden plants. Nosema locustae (grasshopper bait) provides biological control over 3-6 weeks. Pyrethrin or carbaryl spray for direct knockdown. Kaolin clay deters feeding. Cultural: plant trap crops like clover at field margins to concentrate populations for management.

👷 When to Call a Pro

Commercial agricultural operations in high-pressure years use aerial application of malathion or carbaryl coordinated with state departments of agriculture.

❓ FAQ

Are there locusts in the US?

The US had the Rocky Mountain locust, which was once the most numerous vertebrate on Earth — then went extinct around 1902, likely due to agricultural disruption of its breeding areas. Current US grasshoppers can cause locust-like damage in drought years but don't undergo true locust phase transformation.

Why do grasshoppers become plagues?

Drought concentrates grasshoppers in remaining green areas, increasing their density. Crowding triggers serotonin release when hind legs are frequently touched by other grasshoppers — this initiates the phase change from solitary to gregarious behavior. The change is physical (color, wing length) and behavioral (swarming, migration).

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 🦗 Grasshopper & Locust

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.

🦗 Grasshopper & Locust