Florida Termites: Subterranean vs. Drywood (Signs, Risk & Treatments)

Florida has two major termite groups every homeowner should know: subterranean termites (including Formosan) and drywood termites. Their behavior, damage patterns, and treatment options are completely different — and identifying the right species saves thousands in repairs.

Subterranean Termites (Including Formosan)

Subterranean termites are the most destructive species in Florida. They nest in the soil and travel upward into homes looking for cellulose (wood).

• Nesting: Underground — require high moisture.
• Entry: Build mud tubes up foundations, walls, piers, and plumbing penetrations.
• Damage Pattern: Soft, hollow wood; feeding follows the grain.
• Swarm Season in SWFL: Typically spring (Formosan: late spring → summer).
• Risk Level: Highest — colonies can exceed 1 million termites.

Treatment Options

• Trench & Rod Termiticides: Long-lasting soil barrier around the home.
• Foam / Void Treatments: Used when termites enter walls or hollow block.
• Baiting Systems: Monitor activity + eliminate colonies over time.

Drywood Termites

Unlike subterraneans, drywood termites live entirely inside dry wood — no soil contact needed.

• Nesting: Inside furniture, trim, fascia, attic trusses.
• Key Sign: Frass (pellets) — sand-like droppings pushed from kick-out holes.
• Entry: Swarmers squeeze into cracks in siding, soffits, vents.
• Swarm Season in SWFL: Late summer → early fall.

Treatment Options

• Localized Drill & Inject: Ideal for small, contained infestations.
• Whole-Structure Fumigation: Required for widespread, hidden galleries.

How to Tell Which Termites You Have

Look for these clues:

• Mud Tubes = Subterranean termites
• Pellets (frass) = Drywood termites
• Swarmers:
  • Light brown, long wings → Subterranean
  • Reddish, clear wings → Drywood

Unsure? Take clear photos or save samples — our team can ID the species in minutes.

Florida Termite Prevention Checklist

• Fix irrigation overspray and drainage around the foundation.
• Reduce wood-to-soil contact (fences, posts, mulch beds).
• Seal utility penetrations and foundation cracks.
• Replace water-damaged fascia, trim, or siding.
• Schedule an annual inspection.
• Consider a baiting or soil protection plan.