Stachybotrys not always, but almost always exhibits a circular growth pattern forming round colonies of about 1 inch or less to about 1 foot across approximately. Sometimes the circles are complete. Other times, the circles are incomplete and form semi circles or crescent moon shapes when one side of the colony grows but the other side does not grow well, possibly due to a lack of moisture or competition with other mold types on the weaker growing side of the colony.
Also, the mold often forms concentric circles of one circle inside another circle. When this or most molds grows in areas where building materials have been very wet for an extended period of time, such as months as opposed to days or just a few weeks, then the colonies grow into each other this is referred to as confluent growth and the circles are not longer distinguishable and all you see is irregular black patches of mold growth on the wall.
Stachybotrys is an extremely dark black mold. It is often reported to be shiny or slimy in appearance, however, from personal experience, this is only true when the mold is wet. When it is dry, it can be very dark black and powdery. Please note that all the above descriptions will sound wrong to a mold lab tech because the above are descriptions of how the mold looks when it grows on walls.
In a Petri dish the same mold probably does not grow in concentric circles and it looks more fuzzy and may start out whitish, and it turns black later as it produces spores. In Identifying Filamentous Fungi by Guy St-Germain and Richard Summerbell the mold growing in a petri dish can be white, pink, orange, or black on the surface; bottom of the colony can be pale, orange, pink or black. Stachybotrys requires high-cellulose, low-nitrogen food source, such as drywall or cardboard and very soaking wet conditions for an extended period of time.
It is a slow grower. I have seen thousands of Stachybotrys colonies and have never seen it growing on metal objects, air conditioning ducts, or clothes. Its most common habitats in homes appears to be on the underside of wet carpets, or the bottom of wet cardboard boxes or other papers, or on the surface of drywall materials. When it grows on drywall, it is actually growing on the thin paper that coats both surfaces of the drywall.
Copyright: Copyright c 2007-2008 Daryl Watters
About the Author:| Daryl Watters is president of A Accredited Mold Inspection Service, Inc. He provides home, mold, and indoor air quality investigations in South Florida. He is also the creator of MIR forms designed to aid inspectors in the production of computer generated indoor air quality and mold inspection reports. For more information visit http://www.floridamoldinspectors.us http://www.florida-mold-inspection.com |
Article Source: thePhantomWriters Article Submission Service