How to Get Rid of Pesky Fungus Gnats in Your Bald Cypress Tree

If you’ve noticed tiny flying insects hovering around the soil of your beloved bald cypress tree, chances are you’re dealing with fungus gnats. While mostly harmless, these annoying pests can become a nuisance with their incessant buzzing and swarming. As a bald cypress owner myself, I’ve had to wage war against fungus gnats invading my tree. After much trial and error, I’ve discovered some simple yet effective methods to get rid of fungus gnats for good. In this article, I’ll share everything I’ve learned about identifying, preventing, and eliminating fungus gnats in bald cypress trees.

What Are Fungus Gnats?

Fungus gnats are tiny dark flies, about 1/8 inch long, that are attracted to moist soil and decaying plant matter. Unlike fruit flies which feed on produce and liquids, fungus gnats subsist mainly on fungi and mold in potting mix. They lay eggs in topsoil, which hatch into larvae that feed on plant roots and contribute to root rot.

Adult fungus gnats are mostly a nuisance flying around plants and landing on leaves. But their larvae can damage plant roots, stunting growth and spreading plant diseases. Fungus gnats particularly plague seedlings and cuttings trying to form new roots.

Bald cypress trees with their thirst for frequent watering provide the perfect damp environment for fungus gnats to thrive. Left unchecked these annoying insects will be crawling and flying everywhere around your bald cypress. Getting rid of fungus gnats requires addressing both the adult flies and their larvae living in the soil.

Identifying Fungus Gnats

Here are some key signs and behaviors that indicate fungus gnats around your bald cypress

• Tiny flying insects hovering low near the soil surface or potting mix
• Adults are about 1/8 inch long with long legs and antennae
• Dark wings and grayish-black bodies
• Jerky, weak flight pattern with hovering
• Larvae are translucent white worms up to 1/4 inch long
• Adults found near moist soil and decaying plant debris
• Increased activity after watering or rain
• Attracted to light

Fungus gnats can be confused with other small flies like fruit flies or drain flies. But fungus gnats congregate around potted plants, not around drains or produce. Their small size and frail flying pattern also helps distinguish them from other nuisance flies. Examining the soil closely reveals the larvae and confirms fungus gnats.

If you spot swarms of tiny flies busying themselves around potting soil, it’s almost certainly fungus gnats making themselves at home. Identifying them properly is key for applying the right removal methods.

Why Fungus Gnats Are Attracted to Bald Cypress Trees

There are a few reasons why fungus gnats frequently plague bald cypress trees:

• Moist soil – Bald cypress need frequent generous watering to thrive. These moist, wet conditions are ideal fungus gnat habitats.

• Decaysing plant matter – Shed bald cypress needles and leaves provide food for fungus gnat larvae.

• Rich organic potting mixes – Nutrient-dense potting soil encourages fungi growth, feeding adults and larvae.

• Warm weather – Fungus gnat populations boom in warm, humid environments above 60°F.

• Stagnant air indoors – Still air allows fungus gnats to easily fly and reproduce.

• Lack of predators – Without competition, fungus gnat populations explode.

If conditions are right, bald cypresses basically become breeding grounds for invading fungus gnats seeking moist soil and decaying plant matter to feed on. Controlling these conditions is key to warding off fungus gnats.

Problems Caused by Fungus Gnats

Although more annoying than destructive, fungus gnats can cause the following issues:

• Stunted plant growth – Larvae feeding on roots damages plants and slows growth. Seedlings are especially vulnerable.

• Spreading plant diseases – Fungus gnats spread fungal diseases like root rot among plants through contact.

• Annoying swarms of adults – Clouds of flying adult fungus gnats are incredibly distracting and aggravating.

• Sticky honeydew on plants – Larvae secretions create sticky residues on plant leaves that encourage sooty mold growth.

• Psychological distress – Endless swarms of tiny flying insects understandably cause stress for plant owners.

The combination of plant damage and extreme annoyance motivates bald cypress owners to eradicate these insects. Thankfully, there are many effective methods to get rid of fungus gnats for good.

How to Get Rid of Fungus Gnats in Bald Cypress Trees

Here are the best ways I’ve found to eliminate fungus gnats plaguing my bald cypress trees:

Let Soil Dry Out Completely Between Waterings

Fungus gnats need moist soil to thrive. Simply allowing the soil to dry out more between waterings helps control their populations. Wait until the top few inches of soil are completely dry before watering again.

Remove Excess Plant Debris

Clear any dead leaves, needles, and other yard waste surrounding your bald cypress. This decaying organic material provides food for fungus gnat larvae. Removing it starves the larvae.

Use Yellow Sticky Traps

Sticky traps placed just above the soil capture adult fungus gnats. The yellow color attracts the flies. Traps should be checked and replaced regularly as they fill up with insects.

Sprinkle Diatomaceous Earth on Soil

Diatomaceous earth sprinkled on the soil kills fungus gnat larvae through abrasion and drying. It’s non-toxic and safe for plants. Reapply after watering to maintain effectiveness.

Repot with New Sterilized Potting Mix

Repotting your bald cypress in brand new, sterile potting soil eliminates any larvae and fungi living in the old mix. Make sure to sterilize pots too.

Use Systemic Insecticides or Nematodes

Systemic insecticides and beneficial nematodes added to soil kill fungus gnat larvae for long-term control. Always follow label directions carefully.

Set Out Dishes of Apple Cider Vinegar

Apple cider vinegar attracts and drowns adult fungus gnats. Just add a drop of dish soap to break surface tension. Replace vinegar weekly.

Apply Horticultural Oil Spray

Insecticidal horticultural oils sprayed on plants coat and smother both adult and larvae fungus gnats on contact. Avoid plant stress or damage by following label dilution rates.

Install Fans Near Plants

Fans circulating air around plants disturb hovering fungus gnats, making it harder for them to land and reproduce. Air circulation also dries out the soil.

Check for Overwatering Issues

Chronic fungus gnat problems often indicate overwatering. Allowing plants to dry out deprives fungus gnats of their favorite breeding conditions.

Preventing Future Fungus Gnat Infestations

Getting rid of existing fungus gnats is only half the battle. You’ll also want to take preventive steps to stop new infestations:

• Let soil dry out between waterings
• Minimize excess moisture
• Avoid overwatering
• Don’t allow water to pool in saucers
• Provide good ventilation and air circulation
• Remove plant debris and weed regularly
• Use sterile potting mix
• Apply Bacillus thuringiensis israelensis regularly

Making conditions less hospitable for fungus gnats goes a long way towards preventing them. Keeping your bald cypress soil on the drier side is the most important preventive measure.

Be Patient Getting Rid of Fungus Gnats

Eliminating fungus gnats takes some patience once they’ve established themselves. Focus on attacking both adult flies and soil-dwelling larvae simultaneously. Combine several methods for best results.

It can take weeks to fully clear an infestation. Don’t get discouraged! Persist with control measures and you can reclaim your bald cypress. With fungus gnats gone, you can once again enjoy your handsome tree free of annoying hovering insects.