Yes, black mold (Stachybotrys chartarum or Stachybotrys atra.) is a living form of fungus that frequently grows on walls and floors exposed to water, most commonly through humidity, condensation, leaking appliances, or flood events. The black part consists of spores ready to be released. The underlying filaments or hyphae of black mold are mostly hidden.
What Is Black Mold?
Black mold is a common name for many types of fungus that grow on moist surfaces both inside and outside the home. It is neither a virus nor a bacteria. The black mold you see is mainly the black spores produced when it’s trying to reproduce and spread. The core of the fungus are filaments called hyphae that grow deep into the porous gypsum of drywall and along cracks and surfaces in your home.
Does Black Mold Die?
When mold dries out it becomes inactive and stops releasing spores. It does not die quickly and can become reactivated and start growing through your walls and floor if moisture is reintroduced.
Black Mold Life Cycle
Black mold has a 4-stage life cycle beginning with spore germination:
- Spore Germination – Airborne spores land on a suitable surface with available food and moisture. The spores sensing an ideal environment germinate and begin burrowing into the surface with filaments called hyphae.
- Hyphal Growth – Think of hyphae like the new roots of a young plant only these roots aren’t just burrowing. They release enzymes to break down the surface and dig deep into it. This is why fungus is so essential in composting and in the natural environment. It actually dissolves areas around it, consumes what it dissolves, then grows deeper into the substrate. Great for breaking down a compost pile for reuse. Bad for your home’s walls, floors, and wooden framing.
- Spore Formation – After the hyphae have grown and consumed enough food they’ll form being to form black mold spores to help them further spread to new surfaces.
- Spore Release – Once the spores are mature they’ll be released into the air. It’s these spores that you smell when you detect that musty mold odor. It’s also the same spores that are blamed for potential mold health problems.
Once the spores land on a new suitable moist surface with available food they germinate and the cycle begins again.
Is Black Mold A Bacteria Or Virus?
Black mold found on surfaces inside homes is neither a bacteria nor a virus. It’s a fungus. The most common forms have the scientific names Stachybotrys chartarum or Stachybotrys atra. However, there are many more species that could infiltrate your home.
What Does Black Mold Feed On?
Black mold fungus can eat many things: gypsum, carbon rich glue under tiles or wallpaper, exposed and wet wooden surfaces, or even surfaces with enough dust and dirt to feed on.
They desire carbon sources. The most common ones in your home come from plants – starches, cellulose, and lignin. Starches are stored sugars inside plant cell walls. Cellulose and lignin form the building blocks of cell walls for plants. Think of cellulose as the wood framing or fibers and lignins as the glues holding them together.
Plant cells in turn are the building blocks of the wood and drywall inside your home. Both of which are tasty treats for black mold.
Drywall consists of two sheets of paper sandwich around gypsum. The paper is made from trees while the gypsum is made of mined minerals. For drywall, the food source for black mold is the paper surface, not the gypsum core.
Is Black Mold A Form Of Fungi?
Yes, black mold that grows in homes is a form of fungus. The most common species are Stachybotrys chartarum and Stachybotrys atra. They have a four part life cycle that includes spore dispersal, spore germiantion, hyphal growth or burrowing into the walls, followed by spore formation which restarts the cycle in spore dispersal.