Dr. Daniel H. Yocom

Professor, Microbiology, mycology, population biology.

Dr. Daniel H. Yocom

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B.S., Lebanon Valley College
M.S., University of Pittsburgh
Ph.D., State University of New York (SUNY)

Courses Taught:

BIOL 100 – General Biology
BIOL 161/461 – Microbiology
BIOL Environmental Science
BIOL 241 – Principles of Ecology
BIOL 345 – Applied Ecology
BIOL 247 – Biodiversity
BIOL 424 – Mycology
BIOL 546 – Plant Ecology

Areas of Specialization:

Microbiology, Mycology, Population Biology.

Research Interest(s):

Plants growing with mycorrhizae, a mutually beneficial interaction of plant roots with specific soil fungi, are often more vigorous due to increased uptake of mineral nutrients, such as phosphorus. My students and I conducted greenhouse and field experiments designed to examine the importance of the mycorrhizae on agricultural productivity and the impact of environmental factors on the mycorrhizae. Lawns in America cover a land area the size of Virginia, yet relatively few ecologists have studied this manipulated ecosystem. So my students and I conducted experiments to examine the effects of lawn pesticides on decomposition of grass clippings, effects of mowing and fertilization on nutrient leaching, and the effects of mowing on the diversity of insect populations.

Selected Publication(s):

1994. Are crop and weed interaction effected my mycorrhizae? Journal of Pennsylvania Acad. of Sciences 67:175. Drenner, D. D., and D. H. Yocom.

1994. Effects of mycorrhizae on competition between soybeans and weeds. J. of Pennsylvania Acad. of Science 67:181. Hudoch, H. and D. H. Yocom.

1994. The fungi of Southcentral Pennsylvania: a first look. In At the Crossroads: A Natural History of Southcentral Pennsylvania (D. Zegers, editor)

1992. Dependence of three Nebraska Sandhills warm-season grasses on vesicular-arbuscular mycorrhizae. J. of Range Management 46:14-20. Brejda, J. J., D. H. Yocom, L. E. Moser, and S. S. Waller.

1991. Effect of mycorrhizae and nutrient exchange on the growth of interacting corn and bean plants. Bull. Ecol. Soc. Amer. 72(2):297-298. (with D. Weaver)

1991. Effect of VA mycorrhizae on root /shoot ratios of onion. Mycol. Soc. of Amer. Newsletter 42(1):39. (with M. McElvaney)

1991. Mycorrhizal fungi increase yields of winter wheat. In: Keister, D. L. & P. B. Cregan (eds.)The Rhizosphere and Plant Growth.. Kluwer Acad. Pub., Netherlands. p 382. (with M.G. Boosalis)

1987. The effects of prolonged drought on the yield of mycorrhizal and nonmycorrhizal grain crops. In: Mycorrhizal in the Next Decade, Practical Applications and Research Priorities. p 41. (with Boosalis, Flessner, and Cunningham).