Protecting Our Environment Together
Protecting Our Environment Together
Your Guide to the 10 Most Common Pests in Chicago
Table of Contents:
Ants are social insects that live in colonies with thousands to millions of members. Multiple ant species infest Chicago homes, each requiring different treatment approaches.
Carpenter Ants (Most Destructive)
Pavement Ants (Most Common)
Pharaoh Ants (Hardest to Eliminate)
DIY Methods: Ant baits (work on some species, not all)
Professional IPM Approach:
Cockroaches are fast-moving insects attracted to food, moisture, and warmth. They can trigger asthma/allergies and contaminate food with droppings.
German Cockroaches (Most Common Indoors)
American Cockroaches (Larger)
Brown-Banded Cockroaches
DIY Methods: Roach baits (limited effectiveness; usually fails)
Professional IPM Approach:
Timeline: 3-6 weeks for complete elimination
Why DIY Fails: Roaches reproduce so rapidly that single treatment insufficient; requires multi-week approach
Spiders are predatory arachnids that eat other insects. While most are harmless, a few species in Chicago can bite.
House Spiders (Harmless)
Wolf Spiders (Harmless)
Jumping Spiders (Harmless)
Brown Recluse (Venomous – Rare)
Northern Black Widow (Venomous – Rare)
Harmless spiders:
Potentially dangerous:
For Harmless Spiders: Sweep away webs; leave spiders (they eat other pests)
For Potential Venomous Spiders:
Wasps and hornets are aggressive stinging insects that can sting multiple times and pose serious risk to allergic individuals.
Paper Wasps (Most Common)
Bald-Faced Hornets
Yellow Jackets (Most Aggressive)
Honeybees (Don’t Harm Them)
✅ Paper wasp nest near door/window (safety risk)
✅ Bald-faced hornet nest (very aggressive, danger)
✅ Yellow jacket nest (ground nests hard to treat)
✅ Multiple nests on property
❌ Honeybee hive: Call local beekeeper for relocation (not pest control)
❌ Wasp nest far from activity: Leave alone (they eat other insects)
Professional Removal:
Timeline: 1-2 visits
Mosquitoes are blood-feeding insects that can transmit diseases (West Nile Virus, Zika, dengue). Only females bite (need blood for egg production).
Asian Tiger Mosquitoes (Invasive)
Culex Mosquitoes (House Mosquitoes)
Eliminate Standing Water:
Yard Treatment:
Personal Protection:
Treatment Options:
Timeline: Effects last 2-4 weeks; repeat as needed through summer
Fleas are tiny blood-feeding parasites that live on pets and can infest your home. They can jump 150x their body size.
Why it matters: To eliminate fleas, you must break the entire cycle (not just kill adults).
Pet Treatment (Veterinarian):
Home Treatment (Professional):
Timeline: 3-4 weeks for complete elimination
Ticks are arachnids that feed on blood and can transmit Lyme disease, Rocky Mountain spotted fever, and other serious illnesses.
Deer Ticks (Carry Lyme Disease)
American Dog Ticks
Yard Maintenance:
Personal Prevention:
Never:
Do:
Yard Treatment:
Flies are fast-moving insects attracted to food waste and animal feces. Multiple species infest Chicago homes.
House Flies (Most Common)
Fruit Flies
Drain Flies
Bottle Flies & Blow Flies
Source Removal (Most Important):
Professional Treatment:
Earwigs are small, fast-moving insects with pincers at their rear. They prefer moist environments and are mostly harmless.
Prevention:
Treatment:
Stink bugs are shield-shaped insects that release foul odor when crushed. They’re agricultural pests but increasingly common in homes.
Prevention:
Treatment:
| Pest | Danger Level | Call Immediately | Can Wait | Don’t Call (DIY OK) |
|---|---|---|---|---|
| Ants | Low | Carpenter ants | Common ants | — |
| Cockroaches | Medium | Any infestation | — | — |
| Spiders | Very Low | Brown recluse/widow (if identified) | Harmless spiders | House spiders (leave alone) |
| Wasps/Hornets | High | Bald-faced hornets, yellow jackets | Paper wasp nest far away | — |
| Mosquitoes | Medium | Heavy activity/illness risk | Occasional sightings | — |
| Fleas | Medium | If home is infested | Pet only has fleas | — |
| Ticks | Medium | Tick-borne illness suspected | Occasional ticks | Yard prevention |
| Flies | Low | Drain/fruit fly infestation | 1-2 flies | Single fly |
| Earwigs | Very Low | Infestation in basement | Few seen | — |
| Stink Bugs | Very Low | Large gathering/in walls | Few seen | — |