Mold Types

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Alternaria:

Distribution: Alternaria is one of the most common molds and is abundant worldwide. This genus contains around 40 to 50 different species, only a few of which are commonly found indoors.
How it is spread: Alternaria spores are easily dispersed through the air by wind.
Where it is found outdoors: Alternaria is common outdoors in soil, dead organic debris, foodstuffs, and textiles. It is also a plant pathogen and is frequently found on dead or weakened plants.
Where it is found indoors: Alternaria can grow on a variety of substrates indoors when moisture is present.

Acremonium:

Distribution: Acremonium is a common mold, including about 80 to 90 different species.
How it is spread: Acremonium produces wet slimy spores and is normally dispersed through water flow or droplets, or by insects. Old dry Acremonium spores can sometimes be dispersed through the air by wind.
Where it is found outdoors: Acremonium is found in soil, on dead organic material and debris, hay, and foodstuffs.
Where it is found indoors: Acremonium can be found anywhere indoors, but requires very wet conditions in order to proliferate. The spores probably require active disturbance for release.

Aspergillus: (see Penicillium/Aspergillus)

Basidiospores:

Distribution: Basidiospores are produced by a very large and diverse group of fungi called basidiomycetes, which contains over 1000 different genera. This group includes many well-known macrofungi, such as mushrooms. Basidiospores are often abundant in outdoor air and sometimes in indoor air.
How they are spread: Many types of basidiospores are actively released into the air during periods of high humidity or rain. Once the spores are expelled into the air, they are dispersed easily by wind.
Where they are found outdoors: Basidiomycetes are very common outdoors and can be found in gardens, forests, grasslands, and anywhere there is a substantial amount of dead organic material. They are also found on or near plants and some are known to be plant pathogens.
Where they are found indoors: Basidiospores found indoors typically come from outdoor sources and are carried inside by airflow or on clothing. Certain kinds of basidiomycetes can grow indoors, such as those that cause "dry rot", which can cause structural damage to wood. Occasionally, other basidiomycetes such as mushrooms can be found indoors, but this is not common. Generally, basiodiomycetes require wet conditions for prolonged periods in order to grow indoors.

Bipolaris and Dreschlera

Distribution: Bipolaris and Dreschlera are two separate genera of molds that are so visually similar that they are commonly discussed together as a group. Both genera include around 30 - 40 different species.
How they are spread: Bipolaris / Dreschlera spores are easily dispersed through the air by wind.
Where they are found outdoors: Bipolaris / Dreschlera type spores are most abundant in tropical or subtropical climates. They can grow in soils, on plant debris and grasses, and are known to be plant pathogens.
Where they are found indoors: Bipolaris / Dreschlera can grow on a variety of indoor substrates when moisture is present.

Ceratocystis / Ophiostoma:

Distribution: Ceratocystis / Ophiostoma are two separate genera of molds that are so visually similar that they are commonly discussed together as a group. These genera contain around 50 to 60 different species.
How they are spread: Ceratocystis / Ophiostoma produce wet slimy spores and are normally dispersed through water flow, droplets, or by insects. These spores are rarely identified in air samples.
Where they are found outdoors: Ceratocystis / Ophiostoma are very common in commercial lumberyards and forests.
Where they are found indoors: Ceratocystis / Ophiostoma are abundant on wood framing material in the home, although the spores are rarely found in air samples. This mold is sometimes called "lumber mold".

Chaetomium:

Distribution: Chaetomium is a common mold worldwide. This genus contains around 80 - 90 different species.
How it is spread: Chaetomium spores are formed inside fruiting bodies. The spores are released by being forced out
through a small opening in the fruiting body. The spores are then dispersed by wind, water drops, or insects.
Where it is found outdoors: Chaetomium can be found in soil, on various seeds, cellulose substrates, dung, woody materials and straw.
Where it is found indoors: Chaetomium can grow in a variety of areas indoors, but is usually found on cellulose based or woody materials in the home. It is very common on sheetrock paper that is or has been wet.

Cladosporium:

Distribution: Cladosporium is an abundant mold worldwide and is normally one of the most abundant spore types present in both indoor or outdoor air samples. This genus contains around 20 - 30 different species.
How it is spread: Cladosporium produces dry spores that are formed in branching chains. Spores are released by twisting of the spore-bearing hyphae as they dry. Thus, the spores are most abundant in dry weather.
Where it is found outdoors: Cladosporium is found in a wide variety of soils, in plant litter, and on old and decaying plants and leaves. Some species are plant pathogens
Where it is found indoors: Cladosporium can be found anywhere indoors, including textiles, bathroom tiles, wood, moist windowsills, and any wet areas in a home. Some species of Cladosporium grow at temperatures near or below 0(C) / 32(F) and can often be found on refrigerated foodstuffs and even frozen meat.

Curvularia:

Distribution: Curvularia is a cosmopolitan fungus and includes approximately 30 different species.
How it is spread: Curvularia produces dry spores that are formed in fragile chains and is very easily dispersed through the air by wind.
Where it is found outdoors: Curvularia is most common in tropical or subtropical regions. It is found in soil and on debris of tropical plants.
Where it is found indoors: Curvularia can be found growing on a variety of substrates indoors.

Epicoccum:

Distribution: Epicoccum is a cosmopolitan mold that includes only two species.
How it is spread: Epicoccum produces large dry spores that are easily dispersed through the air by wind.
Where it is found outdoors: Epicoccum can be found in soils or on plant debris.
Where it is found indoors: Epicoccum is commonly found on many different substrates indoors including paper, textiles, and insects.

Memnoniella:

Distribution: Memnoniella is a cosmopolitan mold genus that includes approximately five species. It is frequently found in conjunction with Stachybotrys species due to its similar ecological preferences.
How it is spread: Memnoniella produces dry spores that are easily dispersed through the air by wind.
Where it is found outdoors: Memnoniella can be found outdoors in soil, in plant debris or litter, and as pathogens on some types of living plants.
Where it is found indoors: Memnoniella can grow on a variety of substrates indoors, but mainly can be found on wet cellulose-based materials, such as wallboard, jute, wicker, straw baskets, paper and other wood by-products.

Paecilomyces:

Distribution: Paecilomyces is ubiquitous in nature and includes between 9 and 30 different species, depending on the taxonomic system used. Its spores are visually similar to Penicillium / Aspergillus types of spores.
How it is spread: Paecilomyces produce dry spores that are easily dispersed through the air by wind.
Where it is found outdoors: Paecilomyces is found outdoors in soils and decaying plant matter, composting processes, legumes and cottonseeds. Some species parasitize insects.
Where it is found indoors: Paecilomyces can be found on a number of materials indoors. It has been isolated from jute fibers, papers, PVC, timber, optical lenses, leather, photographic paper, cigar tobacco, harvested grapes, bottled fruit, and fruit juice undergoing pasteurization.

Penicillium / Aspergillus:

Distribution: Penicillium / Aspergillus are two separate genera of molds that are so visually similar that they are commonly discussed together as a group. Together, there are approximately 400 different species of Penicillium / Aspergillus.
How it is spread: Penicillium / Aspergillus produce dry spore types that are easily dispersed through the air by wind. These fungi serve as a food source for mites, and therefore can be dispersed by mites and various insects as well.
Where it is found outdoors: Penicillium / Aspergillus are found in soils, decaying plant debris, compost piles, fruit rot and some petroleum-based fuels.
Where it is found indoors: Penicillium / Aspergillus are found throughout the home. They are common in house dust, growing on wallpaper, wallpaper glue, decaying fabrics, wallboard, moist chipboards, and behind paint. They have also been isolated from blue rot in apples, dried foodstuffs, cheeses, fresh herbs, spices, dry cereals, nuts, onions, and oranges.

Stachybotrys:

Distribution: Stachybotrys is ubiquitous in nature. This genus contains about 15 species.
How it is spread: Stachybotrys produces wet slimy spores and is commonly dispersed through water flow, droplets, or insect transport, less commonly through the air.
Where it is found outdoors: Stachybotrys is found in soils, decaying plant debris, decomposing cellulose, leaf litter and seeds.
Where it is found indoors: Stachybotrys is common indoors on wet materials containing cellulose such as wallboard, jute, wicker, straw baskets, and other paper materials.

Torula:

Distribution: Torula is a cosmopolitan microfungus and includes approximately eight different species
How it is spread: Torula produces dry spores that are easily dispersed through the air by wind.
Where it is found outdoors: Torula is most common in temperate regions and has been isolated from soils, dead herbaceous stems, sugar beet roots, groundnuts, and oats.
Where it is found indoors: Torula is common indoors on wet materials containing cellulose, such as wallboard, jute, wicker, straw baskets, and other paper materials.

Ulocladium:

Distribution: Ulocladium is ubiquitous in nature and includes approximately nine different species.
How it is spread: Ulocladium produces dry spores that are easily dispersed through the air by wind.
Where it is found outdoors: Ulocladium is common outdoors in soils, dung, paint, grasses, wood, paper, and textiles.
Where it is found indoors: Ulocladium is common indoors on very wet materials containing cellulose such as wallboard, jute, wicker, straw baskets, and other paper materials. Ulocladium requires a significant amount of water Recommendations