How To Identify Toxic Black Mold

Stachybotrys not always, but almost alwaysPlease note that all the above descriptions will
exhibits a circular growth pattern forming roundsound wrong to a mold lab tech because the
colonies of about 1 inch or less to about 1 footabove are descriptions of how the mold looks
across approximately. Sometimes the circles arewhen it grows on walls. In a Petri dish the same
complete.mold probably does not grow in concentric circles
Other times, the circles are incomplete and formand it looks more fuzzy and may start out
semi circles or crescent moon shapes when onewhitish, and it turns black later as it produces
side of the colony grows but the other side doesspores. In Identifying Filamentous Fungi by Guy
not grow well, possibly due to a lack of moistureSt-Germain and Richard Summerbell the mold
or competition with other mold types on thegrowing in a petri dish can be white, pink, orange,
weaker growing side of the colony. Also, the moldor black on the surface; bottom of the colony
often forms concentric circles of one circle insidecan be pale, orange, pink or black.
another circle. When this or most molds grows inStachybotrys requires high-cellulose, low-nitrogen
areas where building materials have been veryfood source, such as drywall or cardboard and
wet for an extended period of time, such asvery soaking wet conditions for an extended
months as opposed to days or just a fewperiod of time. It is a slow grower. I have seen
weeks, then the colonies grow into each otherthousands of Stachybotrys colonies and have
this is referred to as confluent growth and thenever seen it growing on metal objects, air
circles are not longer distinguishable and all youconditioning ducts, or clothes. Its most common
see is irregular black patches of mold growth onhabitats in homes appears to be on the underside
the wall.of wet carpets, or the bottom of wet cardboard
Stachybotrys is an extremely dark black mold. Itboxes or other papers, or on the surface of
is often reported to be shiny or slimy indrywall materials. When it grows on drywall, it is
appearance, however, from personal experience,actually growing on the thin paper that coats both
this is only true when the mold is wet. When it issurfaces of the drywall.
dry, it can be very dark black and powdery.