PestDecoderDecode a clue

Inspection route

Houseplants pest clues

Moist potting media and decaying roots favor fungus gnats and springtails while fruit flies track fermentation elsewhere.

Inspect in this order

Start where evidence is most likely to remain undisturbed. Photograph scale and placement before cleaning, then establish a clean baseline only when the material can be handled safely.

  1. Test each pot separately.
  2. Inspect soil surface and saucer moisture.
  3. Observe body shape and flight close to the pot.
  4. Let the surface dry appropriately and monitor change.
Avoid this shortcut

Use plant-safe, label-compliant methods only.

Common candidates in this location

Location helps prioritize candidates, but it does not identify a pest by itself. Use a physical sign and companion clue before making a treatment decision.

low concern

Fungus gnat

Sciaridae

Long-legged dark gnats hovering close to moist plant soil, with translucent dark-headed larvae in media.

Larvae and grubsEggs and cases
Read evidence profile
low concern

Springtail

Collembola

Large clusters of tiny specks that spring when disturbed and disappear as the moisture source dries.

Larvae and grubsSounds and movement
Read evidence profile
low concern

Fruit fly

Drosophilidae

Compact tan flies hovering actively around fermenting fruit, beverage residue or recycling.

Larvae and grubsEggs and casesOdors
Read evidence profile
low concern

Booklouse

Psocoptera

Minute pale or gray crawlers on humid books, cardboard or moldy surfaces, without jumping.

Larvae and grubsDamage and gnawing
Read evidence profile

Evidence types worth checking

Larvae and grubs

Hair, head capsule, legs, body curvature and food source distinguish pantry, textile, fly and wood-boring larvae.

10 candidate profiles

Inspect this clue

Eggs and cases

Capsules, clusters and attached cases can separate cockroaches, moths, bed bugs and flies when scale and placement are documented.

8 candidate profiles

Inspect this clue

Sounds and movement

Time of day, route height, rhythm and weight can narrow rodents, squirrels, bats, insects and plumbing-related noise.

6 candidate profiles

Inspect this clue

Odors

Musty, oily, ammonia-like or sewage-associated odors are supporting clues only and should be tied to a physical source.

8 candidate profiles

Inspect this clue

Damage and gnawing

Surface scraping, paired tooth marks, hollow wood, clipped fibers and food-package holes are high-value contextual clues.

12 candidate profiles

Inspect this clue

Build a repeatable baseline

Record the date, exact position and a scale reference. If cleanup is safe, note whether the sign returns in the same route, below the same opening or near the same resource. Repeat location can be more informative than color or a single photograph.

Source basis