Roland Thaxter (August 28, 1858 – April 22, 1932) was an American mycologist, plant pathologist, botanist, and entomologist, renowned for his contribution to the insect parasitic fungi—Laboulbeniales.

His five-volume series on fungi in the order Laboulbeniales laid a solid foundation of research on these insect ectoparasites.

[1] In addition to this literary background, Roland was inspired by nature in his youth, fostering in him an unusual aesthetic sensibility that he brought to his scientific works.

He described the pathogen of potato scab, Oospora scabies,[6] the mildew of lima beans (Phytophthora phaseoli),[6] the onion smut (Urocystis cepulae),[7] and pioneered the use of fungicide sprays to control fungal diseases.

[5] In 1891, Thaxter accepted the call and returned to Harvard, where he combined his interest in Entomology and Mycology to work on insect parasitic fungi in the order Laboulbeniales.

[13] In addition to his intensive studies on Laboulbeniales, Thaxter's research covered topics in Entomology, Botany, Bacteriology, and other groups of fungi.

[16] In 1922, Thaxter published “A revision of the Endogonaceae”, the first monograph of that family in which the morphology and development of Endogone, Glaziella, Sclerocystis, and Sphaerocreas were described and illustrated in detail.

[18] Thaxter was nicknamed “squirt gun botanist”, likely a result of his introduction of fungicide spray methods to American agriculture.

He sailed from Liverpool, New York to Buenos Aires, then traveled to the Falkland Islands and the Strait of Magellan to the southernmost tip of South America.