The most common misunderstanding – and fear – about mold is around a specific mold often incorrectly referred to as “toxic black mold.” However, scientifically there are no molds with the name of “black mold” or “toxic mold.” The correct name is Stachybotrys chartarum.
Here are a few other correct facts about Stachybotrys:
- Most commonly, Stachybotrys is more of a dark greenish-black than pure black.
- There are over 20,000 species of black mold that aren’t Stachybotrys chartarum. The color of Stachybotrys can appear different on drywall and wood than under a microscope, or in a variety of culture plates. It can even appear white or pink depending on the environmental conditions, what it is growing on, and moisture levels.
- You cannot determine toxicity of mold by its color.
- The only way to correctly identify mold is under a microscope by a trained microscopist. Identification is based primarily on the morphology of the spore and the hyphae, not color.*
Examples of Stachybotrys:

On wood; Under a microscope; In a culture plate.

Another culture plate; A different culture plate; NOT Stachybotrys.
For more information on the myths and truths surrounding black mold, read our blog here.
* Based on descriptions by accredited microbiology labs plus the primary training source for microscopy: ww.emlab.com, www.emsl.com, http://www.prestige-em.com, www.qlabusa.com, www.mccroneinstitute.org
** Photos courtesy of Aerotech Labs CD-ROM
*** Microscope photo courtesy of McGregor Pearce https://dehs.umn.edu/stachybotrys-spp
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