What Is Mycology? The Science of Fungi, Explained (2026)

What is mycology?

Mycology is the branch of biology that studies fungi, from the mushrooms on a forest floor to the yeast that raises bread and the rusts and smuts that attack crops. Dictionary.com's short definition is "the branch of biology dealing with fungi," and the people doing the work range from university researchers to amateur club members and home growers of gourmet mushrooms.

The word has a second, narrower sense as well: the fungi found in one area, as in a survey of a county's mycology. Either way the subject is a kingdom of its own, one the University of California Museum of Paleontology describes as closer, chemically and genetically, to animals than to other organisms.

This explainer is built from dictionary definitions, the mycological societies' own published descriptions and named research sources rather than first-hand use.

What mycologists actually study

A mushroom is only the part of a fungus that shows. The National Park Service puts it plainly: often most of the organism grows under the surface, so the mushrooms people notice are only a hint of what is there. Mycology covers the whole organism, hidden threads included, and the UC Museum of Paleontology's introduction to the kingdom groups the reasons it matters roughly like this:

• Decomposition. Fungi break down dead organic material and keep nutrients cycling through ecosystems.
• Partnerships with plants. Most vascular plants could not grow without mycorrhizae, the symbiotic fungi that live in their roots and supply essential nutrients.
• Food and medicine. Fungi give us penicillin and other antibiotics, mushrooms, truffles and morels, and the bubbles in bread, champagne and beer.
• Disease. Fungi cause ringworm and athlete's foot in people, and rusts, smuts and rots that can do severe damage to crops.
• Basic science. Yeasts are standard model organisms for research in genetics and molecular biology.

Because fungi sit so close to animals at the chemical level, the same source notes, fungal infections are hard to treat.

The main branches at a glance

Branch	What it covers	An example from the sources
Taxonomy and systematics	Finding, describing and naming species	About 148,000 accepted species out of an estimated 2.2–3.8 million
Ecology	Decay, nutrient cycling, root partnerships	Mycorrhizae feeding most vascular plants
Medical mycology	Fungal infections of people and animals	Ringworm, athlete's foot
Plant pathology	Fungal diseases of crops	Rusts, smuts, and leaf, root and stem rots
Food and industrial mycology	Antibiotics, baking, brewing	Penicillin; the yeast behind bread and beer
Genetics and cell biology	Fungi as laboratory model organisms	Yeasts
Toxicology	Mushroom poisonings and identification help	NAMA's poison case registry, organized by 1976
Cultivation	Growing gourmet and medicinal species	NAMA's cultivation committee

In practice the rows overlap. A plant pathologist tracking a rust on wheat and a club member recording species for a county list are both doing mycology; what separates them is the question each one is asking, not the organism.

How much of the fungal kingdom is still unknown?

Most of it. A 2022 review by Li-Wei Zhou and Tom May in the journal Mycology works from a practical estimate of 2.2–3.8 million fungal species worldwide, of which only about 148,000, no more than 6.7%, are currently accepted. At the current pace of roughly 2,000 new descriptions a year, the authors write, naming the rest would take at least 1,000 years.

That gap explains why so much of the field is still about collecting and naming. The review argues that a working species pipeline needs every name anchored to a designated type or reference specimen, plus a fully populated DNA sequence database for the species already known. It also makes the case for fieldwork: mycologists, in its words, are in the best position to gather ecological data because they spend the most time with fungi in the natural environment.

The same paper dates the discipline's modern identity to the founding of the International Mycological Association in 1971, after which mycology emerged "as a separate and vibrant discipline."

Professional and amateur mycology

Mycology has a strong amateur tradition running alongside the professional one, and the big societies say so in their own descriptions.

• The Mycological Society of America, founded in 1932, exists to promote "the science of mycology" and to encourage research and education "in all its aspects." Its members come from 40-plus countries and include professionals and amateurs in science, medicine and more.
• The North American Mycological Association (NAMA) joins professional and amateur mycologists through more than 90 affiliated mycological societies in the United States, Canada and Mexico. It calls itself the premier national organization in the US devoted to amateur mycology, runs an annual foray with lectures by professional mycologists, and publishes McIlvainea, a peer-reviewed journal covering all aspects of fungi.
• Local clubs carry much of the day-to-day work. The Mycological Society of San Francisco, founded in 1950 to promote "the understanding and enjoyment of mushrooms and other fungi," opens each general meeting with mushroom identification, keeps a species database, helps with academic research projects and lends identification expertise to the California Poison Control system.

For a newcomer, a local club is the quickest way in: walks, identification tables and experienced members who will correct you on the spot.

How to start learning mycology in 2026

1. Join a club. NAMA's affiliated societies cover much of North America, and meetings like the San Francisco society's open with mushroom identification.
2. Learn the structures before the names. Gill attachment, pore surfaces and spore color are core vocabulary in identification keys. Start with how gill attachment works, then taking a spore print at home, and see what identification diagrams actually teach.
3. Get a book and a lens. David Arora's Mushrooms Demystified is the field reference this site's posts keep pointing to (Check price on Amazon), and a jeweler's loupe brings gills and pores into sharp focus (Check price on Amazon).
4. Grow a gourmet species. NAMA notes that cultivating gourmet and medicinal mushrooms is "becoming increasingly popular, both as a hobby and for profit," and a ready-to-fruit oyster block lets you watch a fungus go from mycelium to mushrooms on a kitchen counter. North Spore's blue oyster kit is one example (Check price on Amazon); you can also see our full shortlist of kits, books and tools (checked October 2026).

The safety rule that comes with the territory

Studying fungi is not the same as eating them. Never eat a wild mushroom without an expert ID. A field guide, an app or one matching feature is not enough, and clubs keep toxicology programs because people do get this wrong; NAMA's toxicology committee had a poison case registry running by 1976. In the US, the San Francisco society lists the Poison Control Center line, 1-800-222-1222, for a suspected poisoning.

Sources

1. Mycology definition — Dictionary.com (checked October 2026)
2. Introduction to the Fungi — University of California Museum of Paleontology (checked October 2026)
3. Mushrooms & Fungi — U.S. National Park Service (checked October 2026)
4. Fungal taxonomy: current status and research agendas for the interdisciplinary and globalisation era — Li-Wei Zhou and Tom W. May, Mycology (via PubMed Central) (checked October 2026)
5. Mycological Society of America — Mycological Society of America (checked October 2026)
6. About Us — North American Mycological Association (checked October 2026)
7. Mushroom Cultivation — North American Mycological Association (checked October 2026)
8. Mycological Society of San Francisco — Mycological Society of San Francisco (checked October 2026)