PEST LIBRARY · IDAHO SPECIES GUIDE · TREASURE VALLEY
Eight Treasure Valley Pests: identification, habitat, treatment
The eight pest species below are the ones Boise Bug Bombers actually treats every week across Boise, Meridian, Nampa, and Eagle. Each species page covers identification, where it lives in the Treasure Valley, how to tell it from common look-alikes, and which service page handles it. Written and maintained by Hillard McMorris, Idaho State Department of Agriculture (ISDA)-licensed Professional Applicator.
What pests are common in Boise, Idaho?
The eight pest species established across Boise, Meridian, Nampa, Eagle, and the broader Treasure Valley are: black widow spider, hobo spider, yellow sac spider, boxelder bug, vole, carpenter ant, house mouse (plus deer mouse), and the wasp/yellowjacket/bald-faced hornet complex. Termites, fire ants, and brown recluse spiders are NOT established in Idaho. Each species below has a dedicated identification page.
Author + Reviewer: Hillard McMorris, Idaho State Department of Agriculture (ISDA)-licensed Professional Applicator. Owner-operator of Boise Bug Bombers. Identifications below are field-confirmed from active appointments across Ada County (Boise, Meridian, Eagle, Garden City) and Canyon County (Nampa, Caldwell) since 2024.
Medically Significant Spiders
Latrodectus hesperus
- Risk level:
- Medically significant
- Season:
- Year-round; peak Aug-Oct
- Treated under:
- Spider Control
Where it lives in the Treasure Valley: Crawl spaces, garage corners, basement window wells, exterior stairwells, rock walls, woodpiles. Established across Ada and Canyon Counties, with highest concentration in Boise Foothills (ZIPs 83703, 83712), Eagle Foothills (83616), and rural-edge Nampa (83687).
ID clues: Glossy jet-black body with the diagnostic red hourglass marking on the underside of the female’s abdomen. Builds messy, three-dimensional cobwebs near ground level. Adult body 8-13 mm; with legs, up to 38 mm.
Often confused with: False widows (Steatoda spp.) have brown-and-cream markings with no hourglass and a smaller, less symmetrical body shape.
Read more:
Eratigena agrestis
- Risk level:
- Bite-significant; toxicity debated
- Season:
- Active May-October
- Treated under:
- Spider Control
Where it lives in the Treasure Valley: Basements, crawl spaces, and ground-level rooms across the Treasure Valley. Most common in 1960s-80s slab-on-grade homes on the Boise Bench (83705, 83709), older Meridian housing (83642), and 12th Ave corridor Nampa (83687).
ID clues: Brown body with a herringbone chevron pattern down the abdomen. Builds funnel-shaped webs in dark corners; does not climb walls well. Body 11-14 mm.
Often confused with: Often confused with brown recluse, which is NOT established in Idaho per University of Idaho Extension and CDC range maps.
Read more:
Cheiracanthium inclusum
- Risk level:
- Nuisance; mild bite
- Season:
- Year-round indoors
- Treated under:
- Spider Control
Where it lives in the Treasure Valley: Wall-ceiling corners, behind picture frames, in stored linens. Active in every Treasure Valley ZIP, especially older Collister + State Street homes (83703, 83714) and North End Boise (83702).
ID clues: Pale yellow to cream-colored body. Active at night. Builds small silken sac retreats. Body 5-10 mm.
Often confused with: Frequently misidentified as brown recluse in Idaho. The brown recluse is not established here; the actual culprit is almost always a yellow sac.
Read more:
Idaho Specialty
Boisea trivittata
- Risk level:
- Nuisance only
- Season:
- Peak Sept-Oct, secondary spring emergence
- Treated under:
- Quarterly Pest Control
Where it lives in the Treasure Valley: South-facing exterior walls of homes with mature box-elder, ash, or maple trees within 200 ft. The classic Treasure Valley October-November call. North End Boise (83702), Bench (83705), Old Town Meridian (83642).
ID clues: Black body with three distinct red-orange stripes on the pronotum. Adults 11-14 mm. Clusters in groups of hundreds to thousands on south-facing surfaces.
Often confused with: Western conifer seed bugs, which are larger, browner, and aggregate differently.
Read more:
Microtus montanus
- Risk level:
- Property damage (turf, irrigation, young trees)
- Season:
- Year-round; peak damage Oct-Apr under snow cover
- Treated under:
- Rodent & Mouse Control
Where it lives in the Treasure Valley: Lawns, landscape beds, and turf adjacent to irrigation canals. Heavy concentration in Winstead Park (83706), Banbury Meadows + Two Rivers Eagle (83616), Tuscany Lakes Meridian (83646), Lake Lowell Nampa (83686).
ID clues: Chunky 4-7 inch body with a blunt, stubby tail (shorter than body). Lives in the lawn and landscape, never the house. Creates surface runways visible after snowmelt.
Often confused with: House mouse (lives indoors, long tail) and pocket gopher (creates mounds, vole does not).
Read more:
Camponotus modoc, Camponotus vicinus
- Risk level:
- Structural damage (tunnels into damp framing)
- Season:
- Indoor activity Mar-Oct; outdoor satellite colonies year-round
- Treated under:
- Ant Control
Where it lives in the Treasure Valley: Damp framing, hollow doors, around plumbing penetrations. Highest pressure in older Bench Boise (83705), Collister (83714), Old Town Meridian (83642), Floating Feather Eagle (83616).
ID clues: Large 1/4 to 3/4 inch body. Black or red-and-black. Single petiole node. Tunnels produce sawdust-like frass (different from termite mud-tubes).
Often confused with: Subterranean termites, which are extremely rare in Idaho’s dry climate. Most ‘termite damage’ in the Treasure Valley turns out to be carpenter ant tunneling.
Read more:
Everywhere Species
Mus musculus, Peromyscus maniculatus
- Risk level:
- Disease vector (deer mouse: hantavirus per CDC); structural + food contamination
- Season:
- Indoor pressure peaks Oct-Mar
- Treated under:
- Rodent & Mouse Control
Where it lives in the Treasure Valley: Attic insulation, kitchen pantries, wall voids, garage corners. Pressure rises Oct-Mar as overnight lows drop. Active in every Treasure Valley ZIP.
ID clues: House mouse: 3-4 inch body with long tail nearly equal to body length, brown-gray fur. Deer mouse: similar size, white belly, larger ears. Deer mouse is the principal hantavirus reservoir per CDC.
Often confused with: Voles (live outdoors, blunt tail) and immature rats (larger body, thicker tail).
Read more:
Polistes spp., Vespula spp., Dolichovespula maculata
- Risk level:
- Sting hazard (multiple species)
- Season:
- Active Apr-Oct; nest peak Jul-Sept
- Treated under:
- Wasp & Hornet Removal
Where it lives in the Treasure Valley: Paper wasps under eaves + soffits. Yellowjackets in ground holes or wall voids. Bald-faced hornets in aerial paper nests in trees. Three vespid species, three nest types, three treatment approaches.
ID clues: Paper wasp: open-celled umbrella nest, slender body. Yellowjacket: hidden nest, banded yellow-black, aggressive at food. Bald-faced hornet: large football-shaped aerial paper nest, black with white face markings.
Often confused with: Mud daubers (build single-cell mud tubes, not social), and honey bees (which are protected; Boise Bug Bombers does not treat honey bees and refers to a beekeeper).
Read more:
Quick service cross-reference
Which Boise Bug Bombers service handles which pest. Cluster + city + pSEO pages link here for the service routing.
Species commonly searched but NOT established in Idaho
National pest control directories list these species generically. None are established in Idaho per University of Idaho Extension, the Idaho State Department of Agriculture (ISDA), and CDC range maps. If you think you have one, the linked species page below is the most likely actual identification.
- Brown recluse spider (Loxosceles reclusa): Not in Idaho. Likely identification: yellow sac spider or hobo spider.
- Subterranean termites (Reticulitermes spp.): Extremely rare in Idaho’s dry climate. Likely identification: carpenter ant.
- Red imported fire ant (Solenopsis invicta): Not established in Idaho. Likely identification: pavement ant. Treated under Ant Control.
- Eastern bed bug treatments + national franchise protocols: Effective in Idaho but require Idaho-specific scheduling around the dry climate. See Bed Bug Treatment + how to tell if you have bed bugs.
Service area for pest identification across the Treasure Valley
Boise Bug Bombers identifies, treats, and provides follow-up pest control for all eight species across Ada County (Boise, Meridian, Eagle, Garden City, Star, Kuna) and Canyon County (Nampa weekly, Caldwell on request). ZIP codes covered include 83702, 83703, 83704, 83705, 83706, 83709, 83712, 83713, 83714, 83716, 83719 (Boise), 83642, 83646, 83680 (Meridian), 83651, 83686, 83687 (Nampa), and 83616 (Eagle).
Frequently Asked Questions
What is the most dangerous spider in Idaho?
The Western black widow (Latrodectus hesperus) is the only spider in Idaho with medically significant venom and a confirmed established population. Bites are rare but require immediate medical attention. Call the Idaho Poison Center at 1-800-222-1222 if bitten and call Boise Bug Bombers at (208) 918-2597 for harborage treatment.
Are brown recluse spiders in Boise?
No. Per University of Idaho Extension and CDC range maps, the brown recluse (Loxosceles reclusa) is NOT established in Idaho. Spider bites attributed to ‘brown recluse’ in Boise are nearly always yellow sac or hobo spider misidentifications.
What is the difference between a vole and a mouse in Idaho?
A vole lives in the lawn and landscape, never the house, has a chunky body with a short blunt tail, and damages turf and irrigation. A mouse lives indoors, has a slender body with a long tail equal to its body length, and contaminates food and insulation. The treatment plan is completely different. See the full vole vs mouse identification guide.
Are termites in Boise, Idaho?
Subterranean termites are extremely rare in Idaho due to the dry climate. The vast majority of reported ‘termite damage’ in the Treasure Valley turns out to be carpenter ant tunneling. If you suspect termites, Boise Bug Bombers will field-confirm during the appointment; if it really is termites, we refer to a structural pest specialist.
When are wasps and hornets most active in the Treasure Valley?
Paper wasps emerge in April. Yellowjacket nest activity peaks July-September, when food-foraging at picnics + garbage cans becomes most aggressive. Bald-faced hornet aerial paper nests reach full size in late summer. Boise Bug Bombers schedules wasp control around the seasonal nest timing for each species.
Sources
Authoritative references for the species identifications and range claims on this page. All third-party links open in a new tab.
