Donald D. Davis, Ph.D.
- B.S., Forestry, Penn State University
- M.S., Forestry, Penn State University
- Ph.D., Plant Pathology, Penn State University
Areas of Interest
Health of hardwood forests of the Northeast; hardwood tree fungal pathogens; etiology of hardwood tree diseases
My general projects are directed towards determining the etiology of hardwood tree diseases and evaluating forest health in the Northeast. Specific current projects include: relative susceptibility of forest plants to ozone; temporal and spatial trends of mercury accumulation in the forest; biocontrol of artillery fungi (Sphaerobolus spp.) using spent mushroom compost; biocontrol of tree-of-heaven (Ailanthus altissima) using Verticillium. Teaching responsibilities include the undergraduate course “Diseases of Forest and Shade Trees” and the graduate course “Diagnosis of Plant Diseases.” In 2008, the latter course was taught in Costa Rica as "Tropical Plant Pathology."
Publications since 2005
Schaub, M., J.M. Skelly, J.W. Zhang, J.A. Ferdinand, J.E. Savage, R.E. Stevenson, K.C. Steiner, D.D. Davis, S.P. Pennypacker. 2005. Physiological and foliar symptom response in the crowns of Prunus serotina, Fraxinus americana, and Acer rubrum canopy trees to ambient ozone under forest conditions. Environ. Pollut. 133:553-567.
Geml, J., Davis, D.D., Geiser, D.M. 2005. Phylogenetic analyses reveal deeply divergent species lineages in the genus Sphaerobolus (Phallales: Basidiomycota). Molecular Phylogenetics and Evolution 35:313-322.
Geml, J., Davis, D.D., Geiser, D.M. 2005. Influence of selected fungicides on in vitro growth of artillery fungi (Sphaerobolus spp.). J. Environ. Hort. 23:63-66.
Geml, J., Davis, D.D., Geiser, D.M. 2005. Systematics of the genus Sphaerobolus based on molecular and morphological data, with the description of Sphaerobolus ingoldii sp. nov. Mycologia 97:680-694.
Davis, D.D., L.J. Kuhns, and T.L. Harpster. 2006. Use of mushroom compost to suppress artillery fungi. J. Environ. Hort. 24:212-215.
Davis, D.D. and T. Orendovici. 2006. Incidence of ozone symptoms on vegetation within a National Wildlife Refuge in New Jersey, USA. Environ. Pollut. 143:555-564.
Davis, D.D. and R.A. Pursell. 2006. Moss and Liverworts Growing on the Mossy Cap Polypore (Oxyporus populinus). Evansia 23:87-91.
Fromm, M. and D.D. Davis. 2007. Abundance of Armillaria within old-growth eastern hemlock stand in south-central Pennsylvania infested with the hemlock wooly adelgid, pp. 169-175 In: Buckley, David S.; Clatterbuck, Wayne K.; [Editors] 2007. Proceedings, 15th central hardwood forest conference. e-Gen. Tech. Rep. SRS–101. U.S. Department of Agriculture, Forest Service, Southern Research Station. 770 p. [CD-ROM].
Davis, D.D., M. Fromm, and M.D. Davis. 2007. Impact of the hemlock woolly adelgid on radial growth of old-growth eastern hemlock in south-central Pennsylvania, pp, 157-162 In: Buckley, David S.; Clatterbuck, Wayne K.; [Editors] 2007. Proceedings, 15th central hardwood forest conference. e-Gen. Tech. Rep. SRS–101. U.S. Department of Agriculture, Forest Service, Southern Research Station. 770 p. [CD-ROM].
Davis, D.D., J.R. McClenahen, and R.J. Hutnik. 2007. Use of the moss Dicranum montanum to evaluate recent temporal trends of mercury accumulation in oak forests of Pennsylvania. Northeastern Naturalist 14:27-34.
McClenahen, J.R., D.D. Davis, and R.J. Hutnik. 2007. Macrolichens as biomonitors of air-quality changes in western Pennsylvania. Northeastern Naturalist 14:15-26.
Davis, D.D. and R.A. Pursell. 2007. Collecting the knothole moss, Anacamptodon splachnoides. Evansia 24:1-5.
Davis, D.D. 2007a. Ozone-induced symptoms on vegetation within the Moosehorn National Wildlife Refuge in Maine. Northeastern Naturalist 14:403-414.
Davis, D.D. 2007b. Ozone injury to vegetation within the Seney National Wildlife Refuge in the Upper Peninsula of Michigan. Northeastern Naturalist 14:415-424.
Orendovici, T., J.M. Skelly, D.D. Davis, J.A. Ferdinand, J.E. Savage, and R.E. Stevenson. 2007. Ozone uptake (flux) as it relates to ozone-induced foliar symptoms of Prunus serotina and Populus maximowizii x trichocarpa. Environ. Pollut. 151:79-92.
Davis, D.D. and R.A. Pursell. 2007. Update--identification of additional bryophytes on the mossy cap polypore (Oxyporus populinus). Evansia 24:49-54.
Davis, D.D. and R.A. Pursell. 2008. Additions to the Pennsylvania bryoflora: Dicranella cerviculata and Pseudoscleropodium purum. Evansia 25:12-14.
Kline, L.J., D.D. Davis, J.M. Skelly, J.E. Savage, and J. Ferdinand. 2008. Ozone sensitivity of 28 plant selections exposed to ozone under controlled conditions. Northeastern Naturalist 15:57-66.
Kline, L.J., J.M. Skelly, D.R. Decoteau, and D.D. Davis. 2009. Variation in ozone sensitivity within Indian hemp and common milkweed selections from the Midwest. Northeastern Naturalist 16:307-313.
Schall, M.J. and D.D. Davis. 2009. Ailanthus altissima wilt and mortality: etiology. Plant Dis. 93:747-751.
Davis, D.D. and R.E. Andrus. 2009. Sphagnum species in coalmine drainages of western Pennsylvania. Evansia 26:15-18.
Davis, D.D. and R.A. Pursell. 2009. Bryophytes on red maple (Acer rubrum) trees in western Pennsylvania. Evansia 26: 124-127.
Fidanza, M.A. and D.D. Davis. 2009. Recycled mushroom compost suppresses bird’s nest fungi in landscape mulch. J. Environ. Hort. 27:238-240.
Davis, D.D. 2009. Ozone-induced stipple on plants in the Cape Romaine National Wildlife Refuge, South Carolina. Southeastern Naturalist 8:471-478.
Fidanza, M.A. and D.D. Davis. 2009. In vitro screening of fungicides to control artillery fungi. J. Environ. Hort. 27:155-158.
Schall, M.J. and D.D. Davis. 2009. Verticillium wilt of Ailanthus altissima: susceptibility of associated tree species. Plant Dis. 93:1158-1162.
Orendovici-Best, T., J.M. Skelly, and D.D. Davis. 2010. Spatial and temporal patterns of ground-level ozone within north-central Pennsylvania forests. Northeastern Naturalist 17:247-260.
Davis, D.D. and J.J. Atwood. 2010. Mosses associated with coalmines and coal seams in western Pennsylvania. Evansia 27:11-17.
Atwood, J.J. and D.D. Davis. 2010. Additional new records of mosses from Pennsylvania. Evansia 27:88-91.
Davis, D.D. and R.A. Pursell. 2010. A list of bryophytes for Wyoming County, PA. Evansia 27: 107-112.
Davis, D.D. 2011. Ozone-induced leaf symptoms on vegetation in the Mingo National Wildlife Refuge, Missouri. Northeastern Naturalist 18:115-122.
Davis, D.D. and M.A. Fidanza. 2011. Fresh recycled mushroom compost suppresses artillery fungi sporulation – a 4-year field study. J. Environ. Hort. 29:91-95.
O’Keefe, G. and D.D. Davis. 2012. First confirmed report that Puccinia horiana, causal agent of chrysanthemum white rust, can overwinter in Pennsylvania. Plant Dis. 96:1381.
Snyder, A.L., S.M. Salom, L.T. Kok, G.J. Griffin, and D.D. Davis. 2012. Assessing Eucryptorrhynchus brandti (Coleoptera: Curculionidae) as a potential carrier for Verticillium nonalfalfae (Phyllachorales) from infected Ailanthus altissima. Biocontr. Sci. & Technol. 22:1005-1019.
McClenahen, J.R., R.E. Showman, R.J. Hutnik, and D.D. Davis. 2012. Temporal changes in lichen species richness and elemental composition on a Pennsylvania atmospheric deposition gradient. Evansia 29:67-73.
McClenahen, J.R., R.J. Hutnik, and D.D. Davis. 2013. Spatial and temporal patterns of mercury bioindicators in Pennsylvania oak forest. J. Env. Qual. 42:305-311.
Kasson, M.T., M.D. Davis, and D.D. Davis. 2013. The invasive Ailanthus altissima in the Pennsylvania: a case study elucidating species introduction, migration, invasion, and growth patterns in the northeastern U.S. Northeastern Naturalist 20 (Monograph 10):1-60.
Snyder, A.L., M.T. Kasson, S.M. Salom, D.D. Davis, G. Griffin, and L.T. Kok. 2013. First report of Verticillium wilt of Ailanthus altissima in Virginia caused by Verticillium nonalfalfae. Plant Dis. 97:837-838.
Rebbeck, J., M.A. Malone, D.P.G. Short, M.T. Kasson, E.S. O’Neal, and D.D. Davis. 2013. First report of Verticillium wilt of Ailanthus altissima in Ohio caused by Verticillium nonalfalfae. Plant Dis. 97:999.
Kasson, M.T., Kerry O’Donnell, Alejandro P. Rooney, Stacy Sink, Randy C. Ploetz, Joshua L. Konkol, Stanley Freeman, Zvi Mendel, Jason A. Smith, Jiri Hulcr, Craig Bateman, Paul Campbell, Andrew Geering, Rajesh Kumar, Keerthi Mohotti, Dylan P.G. Short, Takayuki Aoki, Kristi A. Fenstermacher, Donald D. Davis, and David M. Geiser. 2013. An unordinary fondness for beetles: Phylogenetic diversity of fusaria cultivated by Asian ambrosia beetles Euwallacea (Scolytinae, Xyleborini) on avocado and other plant hosts. Fungal Gen. and Biol. 56:147-157.
Kasson, M.T., E.S. O’Neal, D. Short, K. Subbarao, and D.D. Davis. 2014. Comparative pathogenicity, biocontrol efficacy, and multilocus sequence typing of Verticillium nonalfalfae from the invasive Ailanthus altissima and other hosts. Phytopathology 104:282-292.
Seiler, L., D.R. Decoteau, and D.D. Davis. 2014. Evaluation of Ailanthus altissima as a bioindicator to detect phytotoxic levels of ozone. Northeastern Naturalist 21:541-553.
Hutnik, R.J., J.R. McClenahen, and D.D. Davis. 2014. Mercury accumulation in Pinus nigra (Austrian Pine). Northeastern Naturalist 21:529-540.
Davis, D.D. and B. Allen. 2015. An updated list of bryophytes from Montour County, PA. Evansia 31:189-194.
Kasson, M.T., E.S. O'Neal, and D.D. Davis. 2015. Expanded host range testing for Verticillium nonalfalfae: potential biocontrol agent against the invasive Ailanthus altissima. Plant Dis. 99:823-835.
O'Keefe, G. and D.D. Davis. 2015. Morphology of Puccinia horiana, causal agent of chrysanthemum white rust, sampled from naturally infected plants. Plant Disease 99:1738-1743.
O’Neal, E.S. and D.D. Davis. 2015. Intraspecific root grafting and clonal growth in Ailanthus altissima stands influence Verticillium nonalfalfae transmission. Plant Disease 99:1070-1077.
O’Neal, E.S. and D.D. Davis. 2015. Biocontrol of Ailanthus altissima: Inoculation protocol and risk assessment of Verticillium nonalfalfae (Plectosphaerellaceae: Phyllachorales). Biocontr. Sci. & Technol. 8:950-969.
Baetsen, A.M., J. Kaminski, M.T. Kasson, and D.D. Davis. 2015. Insights into the biology of Sphaerobolus stellatus as a causal agent of thatch collapse in golf turfs. CropScience 55:2342-2351.
Davis, D.D., R.A. Pursell, and B. Allen. 2016. An updated list of bryophytes from Jefferson County, Pennsylvania. Evansia 31:pp-pp. (accepted).
- Biological Control
- Forest Pathology
- Diseases of Vegetables, Fruits, Mushrooms, Ornamentals, and Turfgrasses
- Mushroom Science and Technology
- Plant Disease Management and Adaptive Research Faculty
Clarification of the Puccinia horiana disease cycle in chrysanthemums and related hosts; etiology, dendrochronology, and management of hardwood tree diseases
- Mushroom Science and Technology Faculty
Use of spent mushroom compost to control Sphaerobolus spp. in landscape mulch and to promote health of Christmas trees