Thomas Hawkes Nash III (born November 13, 1945) is an American lichenologist. His research is about the biology and ecology of

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.air pollution Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types ...

on plants and lichens. He is known as an authority on the family

Parmeliaceae The Parmeliaceae is a large and diverse family of Lecanoromycetes. With over 2700 species in 71 genera, it is the largest family of lichen-forming fungi. The most speciose genera in the family are the well-known groups: '' Xanthoparmelia'' ( 822 ...

. During his long career at the

Arizona State University Arizona State University (Arizona State or ASU) is a public research university in the Phoenix metropolitan area. Founded in 1885 by the 13th Arizona Territorial Legislature, ASU is one of the largest public universities by enrollment in the ...

, he helped develop the lichen

herbarium A herbarium (plural: herbaria) is a collection of preserved plant specimens and associated data used for scientific study. The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sheet of paper (called ...

into a world-class collection with over 100,000 specimens representing more than 5000 species. In 2010, the year of his retirement, he was awarded the

Acharius Medal __NOTOC__ The Acharius Medal is awarded by the International Association for Lichenology (IAL) for lifetime achievement in lichenology. The organization resolved at its 1990 meeting that it would simultaneously honor professional achievement and c ...

for lifetime achievements in lichenology, and the following year had a ''

Festschrift In academia, a ''Festschrift'' (; plural, ''Festschriften'' ) is a book honoring a respected person, especially an academic, and presented during their lifetime. It generally takes the form of an edited volume, containing contributions from the h ...

'' published in his honor.

Biography

Nash was born in

Arlington, Virginia Arlington County is a county in the Commonwealth of Virginia. The county is situated in Northern Virginia on the southwestern bank of the Potomac River directly across from the District of Columbia, of which it was once a part. The county is ...

, in 1945. He received a

B.Sc. A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Science was the University of ...

from

Duke University Duke University is a private research university in Durham, North Carolina. Founded by Methodists and Quakers in the present-day city of Trinity in 1838, the school moved to Durham in 1892. In 1924, tobacco and electric power industrialist James ...

in 1967. It was around this time that he was introduced to

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Larry Bliss Lawrence Steven Bliss (born December 29, 1946) is an American educator and former politician from the state of Maine. A Democrat, he served in the Maine House of Representatives (2000–2008) and the Maine Senate (2008–2011). He resigned as a se ...

; he would later take an advanced undergraduate class on lichens given by

William Culberson William Louis "Bill" Culberson (April 5, 1929 in Indianapolis, Indiana – February 8, 2003 in Durham, North Carolina) was an American lichenologist. Professional history Culberson earned his bachelor's degree at the University of Cincinnati, w ...

, and a lichenology summer course given by

Mason Hale Mason Ellsworth Hale, Jr. (September 23, 1929 – April 23, 1990) was one of the most prolific lichenologists of the 20th century. Many of his scholarly articles focused on the taxonomy of the family Parmeliaceae. Hale was one of the first liche ...

. Nash later went on to earn an

M.Sc. A Master of Science ( la, Magisterii Scientiae; abbreviated MS, M.S., MSc, M.Sc., SM, S.M., ScM or Sc.M.) is a master's degree in the field of science awarded by universities in many countries or a person holding such a degree. In contrast to ...

(1969,

botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...

) and

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is a ...

(1971, botany and

statistics Statistics (from German language, German: ''wikt:Statistik#German, Statistik'', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of ...

) from

Rutgers University Rutgers University (; RU), officially Rutgers, The State University of New Jersey, is a Public university, public land-grant research university consisting of four campuses in New Jersey. Chartered in 1766, Rutgers was originally called Queen's ...

, under the supervision of ecologist

Murray Fife Buell Murray Fife Buell (October 5, 1905 – July 3, 1975) was an American ecologist and palynologist. Personal life Born in New Haven, Connecticut, Buell earned a B.S. at Cornell University in 1930. He then attended the University of Minnesota, where h ...

. His Ph.D. thesis, titled ''Effect of Effluents from a Zinc Factory on Lichens'', was later published in the journal ''

Ecological Monographs The Ecological Society of America (ESA) is a professional organization of ecological scientists. Based in the United States and founded in 1915, ESA publications include peer-reviewed journals, newsletters, fact sheets, and teaching resources. I ...

''. Shortly after graduation, he accepted an

assistant professor Assistant Professor is an academic rank just below the rank of an associate professor used in universities or colleges, mainly in the United States and Canada. Overview This position is generally taken after earning a doctoral degree and general ...

ship from

in Tempe, where he has spent much of his scientific career. He was promoted to associate professor of botany in 1976, and became a full professor with this institution in 1981. He taught courses in

ecology Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps wi ...

, lichenology, statistics, and, on one occasion,

bryology Bryology (from Greek , a moss, a liverwort) is the branch of botany concerned with the scientific study of bryophytes (mosses, liverworts, and hornworts). Bryologists are people who have an active interest in observing, recording, classifying or ...

. Nash retired from Arizona State University in 2010. For thirty years Nash and his students investigated Southern California's lichen communities and used them as biomonitors of air quality in the Los Angeles

air basin An air basin is an area within a ring or partial ring of mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from ...

. After his retirement, Nash volunteered with the Wisconsin State Herbarium at the

University of Wisconsin–Madison A university () is an educational institution, institution of higher education, higher (or Tertiary education, tertiary) education and research which awards academic degrees in several Discipline (academia), academic disciplines. Universities ty ...

. Nash has developed a collection of over 110,000 lichen samples for the Arizona State University

, for which he was the curator; about 40,000 of these were collected by Nash himself during his nearly four decades at Arizona State University. The collection features about 450 type specimens, and is represented by about 5,500 different species – about one-quarter of the known lichen species in the world. It is among the ten largest collections of lichens in the United States. His research is largely focused on the biology of

on plants. He uses an

interdisciplinary Interdisciplinarity or interdisciplinary studies involves the combination of multiple academic disciplines into one activity (e.g., a research project). It draws knowledge from several other fields like sociology, anthropology, psychology, ec ...

approach to research, and the topics of his research publications include

ecophysiology Ecophysiology (from Greek , ''oikos'', "house(hold)"; , ''physis'', "nature, origin"; and , '' -logia''), environmental physiology or physiological ecology is a biological discipline that studies the response of an organism's physiology to enviro ...

, ecology,

taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

floristics {{Short pages monitor