What wasp is nesting in the ground in my New Hampshire lawn?

In New Hampshire, the ground-nesting wasp you find is almost always one of three things: an eastern yellowjacket colony (Vespula maculifrons), which is the one that warrants professional treatment; an eastern cicada killer (Sphecius speciosus), which is solitary, docile, and harmless; or a great black wasp or related digger wasp, also solitary and harmless. The fast way to tell: one entrance hole with a steady, defensive stream of wasps that get agitated when you get close — that is a yellowjacket colony. Many separate holes across an area, each with a single large calm wasp, means harmless solitary diggers. Use the decision tree on this page to reach a verdict before you do anything else.

Are ground wasps dangerous to kids and pets?

It depends entirely on the species. Yellowjacket ground nests are genuinely dangerous — especially to children and pets who might disturb them by mowing, running, or digging nearby. A mature colony can hold 1,000 to 3,000 or more workers that sting repeatedly and will chase an intruder. Vibration from a lawnmower is one of the most common triggers for mass-stinging events. Solitary ground nesters — cicada killers, great black wasps, digger wasps — are not dangerous to kids or pets. They have no colony to defend, and females sting only if handled directly; males of most species cannot sting at all. The key is identifying which type you have before anyone or anything goes near it.

How do I tell yellowjackets from harmless ground wasps?

Use the UMD Extension field test. First, look at the entry pattern: one hole in the ground with a steady, busy stream of wasps flying in and out, and wasps that act defensively when you approach or when the lawn vibrates — that is a social yellowjacket colony. Now look at what else is happening: if there are many separate holes spread across a patch of bare or sandy soil, and each hole has only one or two large wasps that move calmly and ignore you, those are harmless solitary diggers (cicada killers, great black wasps, or digger wasps). The defensive attitude is the clearest cue: yellowjacket colonies react; solitary wasps go about their business. If you are not certain, call a professional to confirm before treating.

Should I kill the ground wasps in my lawn?

Only if you have confirmed it is an aggressive social yellowjacket nest in a location where people, children, or pets are likely to disturb it. Yellowjacket ground nests near foot traffic, garden beds, play areas, or in stone walls where gardening occurs are a legitimate hazard and warrant professional removal. Leave solitary digger wasps — cicada killers, great black wasps, steel-blue cricket hunters — completely alone. They are beneficial predators (cicada killers hunt cicadas; great black wasps hunt katydids and grasshoppers) and are gone by fall without intervention. Treating a harmless solitary digger wasp achieves nothing except harming a beneficial insect.

How do I get rid of a yellowjacket ground nest in New Hampshire?

The reliable method is professional dust treatment of the entrance at night, when workers are inside the nest and less active. A licensed applicator applies an EPA-registered insecticidal dust into the nest entrance; workers contacting the residue die within 24–48 hours, and the colony collapses. This is the approach UNH Cooperative Extension recommends for social ground nests. Anchor Pest Services performs ground-nest removal across southern and central NH for a flat one-time rate, treats after dark, and includes an approximately 30-day re-treat guarantee. NH license #782664, category F1 under RSA 430.

Can I pour gasoline or boiling water down a wasp hole?

No — do not do this. Pouring gasoline into a ground nest is hazardous (fire and explosion risk, toxic fumes), environmentally harmful, and illegal under NH pesticide law (RSA 430) since gasoline is not a registered pesticide. Boiling water is ineffective — the colony extends well below the surface, and water cools rapidly before reaching the queen or most of the brood. Both methods also damage your lawn and can kill surrounding plants. NC State Extension explicitly warns against both. The only proven-reliable and legal DIY option for a small, accessible nest is a labeled wasp/hornet aerosol applied at the entrance after dark — but if you have any doubt, call a licensed professional.

Are cicada killer ground nests dangerous?

No. Cicada killers (Sphecius speciosus) are solitary wasps — each female digs her own burrow, has no colony to defend, and is remarkably docile. Oklahoma State Extension describes them as 'unusually docile and harmless.' Females will sting only if you catch, squeeze, or sit on one; males act territorial and may hover or buzz at you, but male cicada killers have no stinger and cannot sting at all. The burrows in bare or sandy soil can be unsightly, and heavy concentrations in a lawn are occasionally a turfgrass concern, but the wasps themselves pose essentially no sting risk to people who leave them alone. They are gone by late summer once cicada season ends.

Why is it dangerous to mow over a ground wasp nest?

Vibration is one of the most reliable triggers for a yellowjacket colony to deploy its defense response. Running a lawnmower over or near a yellowjacket ground nest — even without directly striking the entrance — can send vibrations through the soil that the colony interprets as an attack. The defensive response is immediate and involves many workers stinging whatever is closest. Mowing incidents are among the most common causes of serious yellowjacket mass-sting events in New Hampshire. If you suspect a ground nest in your yard, stop mowing in that area and mark the location until you have confirmed what it is and either treated it or verified it is a harmless solitary digger.

Do ground wasps come back to the same hole each year?

Yellowjacket colonies do not reuse last year's nest. Every spring, a newly mated queen that survived winter starts a fresh colony from scratch — she may choose the same general area if the soil conditions are favorable, but the old nest is abandoned. Solitary digger wasps such as cicada killers also build fresh burrows each season. That said, sites with ideal conditions (sunny, bare or sandy soil, low foot traffic) will attract new colonies year after year because the habitat remains attractive. If you had yellowjackets in the same spot for two or three seasons, habitat modification — filling the void, seeding bare soil, addressing soil drainage — reduces future attraction.

Who removes yellowjacket ground nests near Manchester, Nashua, and Concord NH?

Anchor Pest Services removes yellowjacket and social-wasp ground nests across 15 cities in southern and central New Hampshire — including Manchester, Nashua, Concord, Derry, Bedford, Salem, Hudson, Amherst, Auburn, Goffstown, Hooksett, Litchfield, Loudon, Milford, and Bristol, and across Rockingham, Hillsborough, Merrimack, and Strafford counties. The service is a single flat-rate one-time Wasp & Hornet removal — get a quote, no tiers or per-nest upcharges. Anchor confirms species before treating (honey bees are never treated — they are referred to a licensed NH beekeeper for live relocation) and carries an approximately 30-day re-treat guarantee. NH commercial applicator license #782664, category F1 (Industrial/Institutional/Structural/Health-Related) under RSA 430, administered by NHDAMF. Member NEPMA. Call (603) 785-0118.

Daniel Brady · NH-Licensed Pesticide Applicator · License #782664

|Reviewed by Daniel Brady

Ground Wasps in NH — What's Nesting in Your Lawn?

Identification

"Ground wasp" is a behavior, not a single species. In New Hampshire, a hole in the lawn is almost always one of three things: aggressive Vespula yellowjackets (the only one that needs professional treatment), docile eastern cicada killers, or other harmless solitary digger wasps. One hole with a steady defensive stream of wasps means yellowjackets — call a pro. Many separate holes, each with a single calm wasp, means harmless solitary diggers — leave them alone.

Quick facts

Aggressive ground nester in NH: Yellowjacket (Vespula maculifrons) — TREATSocial colony; repeat stings; NC State Extension
Harmless ground nesters in NH: Cicada killer, great black wasp, steel-blue cricket hunter — LEAVESolitary; docile; UMD Extension / OK State Extension
Yellowjacket colony size: 1,000–3,000+ workers at peakNC State Extension; Wikipedia / Ohio State put mature nests higher (~4,000–5,000 workers)
Field test: 1 hole + defensive stream = treat; many holes + 1 calm wasp each = leaveUMD Extension

Aggressive ground nester in NH
Yellowjacket (Vespula maculifrons) — TREAT
Social colony; repeat stings; NC State Extension
Harmless ground nesters in NH
Cicada killer, great black wasp, steel-blue cricket hunter — LEAVE
Solitary; docile; UMD Extension / OK State Extension
Yellowjacket colony size
1,000–3,000+ workers at peak
NC State Extension; Wikipedia / Ohio State put mature nests higher (~4,000–5,000 workers)
Field test
1 hole + defensive stream = treat; many holes + 1 calm wasp each = leave
UMD Extension

Overview

What's actually nesting in your New Hampshire lawn?

A hole in the lawn with wasps flying in and out is one of the most startling things a New Hampshire homeowner finds in July or August — and the most important question is not "what killed it" but "which wasp is it?" Because the right answer determines everything: do you call a professional, or do you leave it completely alone?

"Ground wasp" is not a species. It is a description of a nesting behavior shared by wasps that are completely different in their danger level and what to do about them. In New Hampshire, the three ground-nesting wasps you are realistically going to encounter are: (a) Vespula yellowjackets — social, colony-forming, repeat-stinging, and the only ground-nesting wasp in NH that genuinely warrants professional removal; (b) the eastern cicada killer — a large, solitary, docile wasp that digs individual burrows in bare or sandy soil and is essentially harmless; and (c) the great black wasp and related solitary digger wasps — also solitary, also harmless, also beneficial.

The fastest way to tell them apart is a field test developed by UMD Extension: a single entrance hole with a steady, defensive stream of wasps that get agitated when you approach or mow nearby — that is a yellowjacket colony. Many separate holes across an area, each with one or two large calm wasps that ignore you — that is harmless solitary diggers. This page walks you through that decision in three questions, tells you what each outcome means, and explains the one safety rule that matters most: never pour gasoline or light a fire in a ground nest.

If your decision tree points to yellowjackets, this is a job for a licensed professional — not because the wasp is exotic, but because a mature colony of 1,000 to 3,000 workers defending an underground nest is a medical emergency waiting to happen for anyone who disturbs it. Anchor Pest Services serves 15 cities across southern and central New Hampshire, confirms species before treating, and removes social ground nests for a flat one-time rate — contact for a quote.

New Hampshire context

Ground-nesting wasps in southern and central New Hampshire

Ground-nesting wasps are active across all of Anchor's 15-city service area — in Manchester, Nashua, Concord, Derry, Bedford, Salem, Hudson, Amherst, Auburn, Goffstown, Hooksett, Litchfield, Loudon, Milford, and Bristol, and across Rockingham, Hillsborough, Merrimack, and Strafford counties. The eastern yellowjacket (Vespula maculifrons) is the dominant ground-nesting species in NH and the one responsible for the overwhelming majority of lawn-sting incidents. It nests in abandoned rodent burrows, stone-wall bases, and loose soil across the region. NH's characteristic stone walls — a feature of older properties throughout the seacoast and Lakes Region fringe — are prime yellowjacket habitat: the base of a stone wall gives a colony a protected, insulated cavity that is difficult to treat and easy to disturb while gardening. If you have an active stone-wall nest, treat it with the same respect as any concealed void nest. The eastern cicada killer is present in NH but uncommon, appearing near the northern edge of its range. An authentic homeowner report from Plaistow, NH, and data from the Massachusetts Cicadas project confirm that cicada killers do occasionally appear in southern NH, typically in July and August in sandy or bare-soil areas — lawns, garden edges, between pavers. They are solitary and harmless wherever they occur. Yellowjacket colonies ramp up through summer and reach peak population and aggression in August and September, exactly when cookout season peaks. Manchester's first hard frost falls around October 19 (50% probability) or October 29 (80%), per NOAA 1991–2020 normals — so an active late-August ground nest in Manchester still has six to ten weeks of growing season left. Waiting it out is not a safe strategy.

Species present in NH

Eastern yellowjacket (Vespula maculifrons)
Eastern cicada killer (Sphecius speciosus)
Great black wasp (Sphex pensylvanicus)
Steel-blue cricket hunter (Chlorion aerarium)
Double-banded scoliid wasp (Scolia bicincta)

Peak activity · August through mid-September (yellowjackets); July–August (cicada killers)

We serve these communities

ManchesterNashuaConcordDerryBedfordSalemHudsonAmherstAuburnGoffstownHooksettLitchfieldLoudonMilfordBristol

First-frost anchor: Manchester first hard frost ~Oct 19 (50%) / Oct 29 (80%) per NOAA 1991–2020 normals — yellowjacket colonies remain active until then

UNH Cooperative Extension (Resource000532) recommends treating ground-nesting social-wasp colonies after dark with a labeled product and exiting the area immediately, or calling a licensed professional — particularly for anyone with a history of allergic reactions to wasp venom.

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Same-day service
Family-owned since 2017

Service Area Map

Southern New Hampshire

Field identification

What's actually nesting in your NH lawn — the 3-branch decision

Three field marks let you sort any ground-nesting NH wasp in under a minute — without getting close enough to provoke a reaction.

Nest entry pattern

One busy, defensive hole = social colony (yellowjacket). Multiple calm, low-traffic holes spread across bare soil = solitary diggers. This single observation is the most reliable first sort.

Traffic and behavior

Steady two-way traffic with defensive posturing when you approach = yellowjacket workers. Single calm wasps that ignore humans and move slowly = solitary females provisioning their own burrow.

Body color and size

Chunky black-and-yellow wasps the size of a yellowjacket = almost certainly yellowjackets. Very large wasp (30–50 mm, roughly the width of two US quarters) with rusty-red thorax and yellow-banded abdomen = cicada killer. Very large all-glossy-black wasp with smoky blue-iridescent wings = great black wasp.

Soil mound vs bare hole

Cicada killers leave a conspicuous mound of loose excavated soil at each burrow entrance — like a rough C-shaped arc. Yellowjacket entrances are usually cleaner holes with worn paths but no large soil mound. Great black wasps dig less conspicuous openings in compact soil.

Common look-alikes

Eastern cicada killer (mistaken for a 'giant yellowjacket' or murder hornet)
How to tell: Cicada killers are much larger (30–50 mm — up to twice the width of a quarter) and have a rusty-red or orange head and thorax, unlike the all-black-and-yellow pattern of a yellowjacket. They are solitary and completely calm. The murder hornet (Vespa mandarinia) was declared eradicated from the entire US on December 18, 2024, and was never found in New Hampshire or anywhere in New England. The huge wasp in your NH lawn in July is a cicada killer.
Great black wasp (mistaken for a steel-blue cricket hunter or European hornet)
How to tell: The great black wasp (Sphex pensylvanicus) is entirely matte to glossy black with smoky blue-iridescent wings. The similar steel-blue cricket hunter (Chlorion aerarium) has a distinct metallic steel-blue sheen — the blue color is the tell. Neither is the European hornet, which is a large brown-and-yellow wasp attracted to lights at night and nests in tree cavities or wall voids, not open soil burrows.
Yellowjacket ground nest (mistaken for a harmless bee nest)
How to tell: Yellowjackets at a ground entrance look similar to bumblebees at a glance — both are yellow-and-black and low to the ground — but yellowjackets are smooth and hairless, move faster, and react aggressively when you approach. Bumblebee ground nests are far less common in lawns and the bees are noticeably fuzzy. Anchor always confirms species before treating; honey bees and bumble bees are referred to a licensed NH beekeeper for relocation, never treated.

NH ground-nesting wasps: treat vs. leave

Prevalence based on UNH Cooperative Extension survey data.

Species	Size	NH status	Prevalence	Typical nest
Eastern yellowjacket Vespula maculifrons	12 worker / 18 queen mm	Native	HIGH	Single ground hole (abandoned rodent burrow or self-dug void); stone-wall bases; lawn edges; defensive, busy traffic
Eastern cicada killer Sphecius speciosus	30–50 mm	Range-expanding	LOW	Single deep burrow (10–20 in) in bare or sandy soil with a soil mound at entrance; one wasp per hole; calm behavior
Great black wasp / digger wasps Sphex pensylvanicus and related Sphecidae	20–35 mm	Native	MEDIUM	Scattered single burrows in compact or sandy soil; calm wasps that ignore people; no defensive behavior

Species

Size

NH status

Prevalence

Typical nest

Eastern yellowjacket

Vespula maculifrons

12 worker / 18 queen mm

Native

HIGH

Single ground hole (abandoned rodent burrow or self-dug void); stone-wall bases; lawn edges; defensive, busy traffic

Eastern cicada killer

Sphecius speciosus

30–50 mm

Range-expanding

LOW

Single deep burrow (10–20 in) in bare or sandy soil with a soil mound at entrance; one wasp per hole; calm behavior

Great black wasp / digger wasps

Sphex pensylvanicus and related Sphecidae

20–35 mm

Native

MEDIUM

Scattered single burrows in compact or sandy soil; calm wasps that ignore people; no defensive behavior

Quick ID quiz

Answer three questions about what you see in your lawn. Each answer takes you toward a verdict — and the verdict tells you whether to call a professional or leave the wasps alone. If you have any doubt, stop and call before approaching closer.

How many entrance holes do you see?

Common Questions

Frequently asked

References

Sources & further reading (12)

[1]
NC State Extension — Yellowjackets
extension · Eastern yellowjacket colonies up to ~3,000 workers; no gasoline or fire in ground nests; field identification guidance · verified Jun 2026
[2]
Penn State Extension — Eastern Yellowjacket (Vespula maculifrons)
extension · Ground-nesting behavior; repeat stings; do not plug wall-void entrance; worker 12 mm / queen 18 mm sizes · verified Jun 2026
[3]
Wikipedia — Yellowjacket
encyclopedia · Eastern yellowjacket builds nests underground; peak worker population 1,000–3,000 individuals; repeat stinging; smooth unbarbed stinger · verified Jun 2026
[4]
UMD Extension — Predatory Wasps / Social Wasps
extension · Field test: single hole + steady defensive stream = social ground nest (treat); many holes + 1–2 wasps each = harmless solitary diggers (leave); solitary wasps sting only if handled · verified Jun 2026
[5]
UNH Cooperative Extension — Controlling Wasps, Bees and Hornets Around Your Home
extension · After-dark professional dust treatment as the reliable NH method; foundress overwintering; nests not reused; NH colony calendar · verified Jun 2026
[6]
Oklahoma State Extension — Cicada Killers
extension · Eastern cicada killer described as 'unusually docile and harmless'; females rarely sting; males cannot sting · verified Jun 2026
[7]
Illinois DNR — Cicada Killer
gov · Burrow depth 10–20 inches; solitary; active July–August; docile behavior · verified Jun 2026
[8]
University of Minnesota Extension — Great Black Wasp
extension · Great black wasp solitary and docile; stings only if handled; males cannot sting; beneficial katydid/grasshopper hunter · verified Jun 2026
[9]
Massachusetts Cicadas / New England Cicada Research — Cicada Killers of New England
extension · Cicada killer NH records sparse (Plaistow NH homeowner report); records 'extremely lacking especially in Vermont, New Hampshire and Maine' · verified Jun 2026
[10]
NOAA / The Old Farmer's Almanac — NH Frost Dates (Manchester, 1991–2020 normals)
gov · Manchester first hard frost ~Oct 19 (50%) / Oct 29 (80%); colony collapse calendar · verified Jun 2026
[11]
Michigan State University — Yellowjackets
extension · Yellowjacket nests not reused; new queens overwinter and start fresh colonies each spring · verified Jun 2026
[12]
Northern New England Poison Center
medical · 24/7 poison control for NH/ME/VT; 1-800-222-1222; anaphylaxis signs · verified Jun 2026

Written & reviewed by

Verified

Daniel Brady

NH-Licensed Pesticide Applicator · License #782664 (NHDAMF, RSA 430)

Daniel Brady is the New Hampshire–licensed applicator behind Anchor Pest Services, a family-owned pest control company serving the Manchester area since 2017.

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Last updated Jun 2026

Anchor Pest Services

Wasps gone — and they stay gone.

Same-day service across Southern New Hampshire. NH-licensed #782664, family-owned since 2017. We handle ground, wall, and aerial nests with EPA-registered products and an approximately 30-day re-treat guarantee.

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Keep Exploring

Ground Wasps in NH — What's Nesting in Your Lawn?

What's actually nesting in your New Hampshire lawn?

Ground-nesting wasps in southern and central New Hampshire

What's actually nesting in your NH lawn — the 3-branch decision

Nest entry pattern

Traffic and behavior

Body color and size

Soil mound vs bare hole

Common look-alikes

Eastern cicada killer (mistaken for a 'giant yellowjacket' or murder hornet)

Great black wasp (mistaken for a steel-blue cricket hunter or European hornet)

Yellowjacket ground nest (mistaken for a harmless bee nest)

NH ground-nesting wasps: treat vs. leave

How many entrance holes do you see?

Frequently asked

Sources & further reading (12)

Wasps gone — and they stay gone.

Your next step

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How to Get Rid of Cicada Killer Wasps

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Cicada Killer Wasp — Quick ID for New Hampshire

How Can I Tell if I'm Dealing With Wasps or Bees Before Attempting Removal?