Bird's Nest Fungus in Mulch: Harmless but Unsightly – How to Manage It

After a hurricane brought 7–8 days of rain, a newly mulched bed sprouted "bird's nest fungus" everywhere. The homeowner worried about effects on new shrubs and trees.

It's a Nuisance, Not a Threat

Bird's nest fungus (Crucibulum spp.) is a saprophyte—it feeds on decaying wood and mulch. It does not attack living plants.

Simple Controls

• Blast the "nests" apart with a strong jet of water as soon as they appear.
• Fluff the mulch regularly to speed drying.
• Spray with Bordeaux mix or copper soap fungicide to suppress recurrence.
• Home remedy: 1 part dishwashing liquid to 20 parts water, poured over the area.

Long-Term

As the mulch ages and breaks down completely, the fungus naturally disappears.