Title: Research Ecologist
Unit: Sustaining Forests in a Changing Environment
Address: Northern Research Station
PO Box 267
Irvine, PA 16329
E-mail: Contact Alex Royo
Jump to Publications
- Ph.D. Ecology and Evolutionary Biology; University of Pittsburgh, 2005
- M.S. Department of Biological Sciences; University of North Carolina, Greensboro, 1998
- B.A. Department of Biological Sciences; University of North Carolina, Greensboro, 1993
- Graduate Certificate of Latin American Studies; University of Pittsburgh, 2005
Civic & Professional Affiliations
Ecological Society of America
My main research focus investigates the role of competition by understory plants and herbivory by ungulates and small mammals in the diversity and abundance of tree seedlings in the understory before overstory gap formation. Furthermore, I am involved in several projects elucidating the role mammalian herbivores play in the maintenance of herbaceous plant communities across a wide latitudinal gradient.
Why is This Important
Among the many factors that determine forest understory diversity prior to any overstory disturbance, competition and herbivory are typically thought of as preeminent. Understanding how these two factors, alone and in concert, act to promote or reduce plant diversity is key to the sustainable management of forest resources.
I plan on continuing my research programs on the maintenance of herbaceous species diversity in both temperate and tropical systems. I also plan on examining the potential for developing alternatives to herbicide application for the control of understory herbaceous interference. Additional research interests involve regeneration of forest systems following catastrophic wind disturbance and subsequent salvaging as well as the impact of soil-borne pathogens on early tree establishment.
- Peterson, Chris J.; Krueger, Lisa M.; Royo, Alejandro A.; Stark, Scott; Carson, Walter P. 2013. Disturbance size and severity covary in small and mid-size wind disturbances in Pennsylvania northern hardwoods forests. Forest Ecology and Management. 302: 273-279.
- Nuttle, Tim; Royo, Alejandro A.; Adams, Mary Beth; Carson, Walter P. 2013. Historic disturbance regimes promote tree diversity only under low browsing regimes in eastern deciduous forest. Ecological Monographs. 83: 3-17.
- Royo, Alejandro A.; Ristau, Todd E. 2012. Stochastic and deterministic processes regulate spatio-temporal variation in seed bank diversity. Journal of Vegetation Science
- Dey, Daniel C.; Royo, Alejandro A.; Gardiner, Emile S.; Cardenas, Luis Mario. 2012. Sustaining Quercus humboltii and Colombobalanus excelsa on the Colombian landscape: preservation or conservation - a research perspective. In: Butnor, John R., ed. Proceedings of the 16th Biennial Southern Silvicultural Research Conference; 2011 February 14-17; Charleston, SC. Gen. Tech. Rep. e-GTR-SRS-156. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station: 88-90.
- Royo, Alejandro A.; Knight, Kathleen S. 2012. White ash (Fraxinus americana) decline and mortality: the role of site nutrition and stress history. Forest Ecology and Management. 286: 8-15.
- Goetsch, Chandra; Wigg, Jennifer; Royo, Alejandro A.; Ristau, Todd; Carson, Walter P. 2011. Chronic over browsing and biodiversity collapse in a forest understory in Pennsylvania: Results from a 60 year-old deer exclusion plot. The Journal of the Torrey Botanical Society. 138(2): 220-224.
- Royo, Alejandro A.; Heartsill Scalley, Tamara; Moya, Samuel; Scatena, Fred N. 2011. Non-arborescent vegetation trajectories following repeated hurricane disturbance: ephemeral versus enduring responses. Ecosphere. 2(7): art 77. doi: 10.1890/ES11-0018.1
- Kain, Morgan; Battaglia, Loretta; Royo, Alejandro; Carson, Walter P. 2011. Over-browsing in Pennsylvania creates a depauperate forest dominated by an understory tree: results from a 60-year-old deer exclosure. Journal of the Torrey Biological Society. 138(3): 322-326.
- Dey, Daniel C.; Royo, Alejandro A.; Brose, Patrick H.; Hutchinson, Todd F.; Spetich, Martin A.; Stoleson, Scott H. 2010. An ecologically based approach to oak silviculture: a synthesis of 50 years of oak ecosystem research in North America. Revista Columbia Forestal. 13(2): 201-222.
- Reinhart, Kurt O.; Royo, Alejandro A.; Kageyama, Stacie A.; Clay, Keith. 2010. Canopy gaps decrease microbial densities and disease risk for a shade-intolerant tree species. Acta Oecologica. 36: 530-536.
- Knight, Kathleen S.; Herms, Daniel A.; Cardina, John; Long, Robert; Rebbeck, Joanne; Gandhi, Kamal J.K.; Smith, Annemarie; Klooster, Wendy S.; Herms, Catherine P.; Royo, Alejandro A. 2010. Emerald ash borer aftermath forests: The dynamics of ash mortality and the responses of other plant species. In: Michler, Charles H.; Ginzel, Matthew D., eds. 2010. Proceedings of symposium on ash in North America; 2010 March 9-11; West Lafayette, IN. Gen. Tech. Rep. NRS-P-72. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station: 11.
- Royo, Alejandro A.; Collins, Rachel; Adams, Mary Beth; Kirschbaum, Chad; Carson, Walter P. 2010. Pervasive interactions between ungulate browsers and disturbance regimes promote temperate forest herbaceous diversity. Ecology. 91(1): 93-105.
- Royo, Alejandro A.; Stout, Susan L.; deCalesta, David S.; Pierson, Timothy G. 2010. Restoring forest herb communities through landscape-level deer herd reductions: Is recovery limited by legacy effects? . Biological Conservation. 143: 2425-2434.
- Royo, Alejandro A.; Carson, Walter P. 2010. The formation of dense understory layers in forests worldwide: consequences and implications for forest dynamics, biodiversity, and succession. In: Pye, John M.; Rauscher, H. Michael; Sands, Yasmeen; Lee, Danny C.; Beatty, Jerome S., tech. eds. Advances in threat assessment and their application to forest and rangeland management. Gen. Tech. Rep. PNW-GTR-802. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station: 469-496.
- Krueger, Lisa M.; Peterson, Chris J.; Royo, Alejandro; Carson, Walter P. 2009. Evaluating relationships among tree growth rate, shade tolerance, and browse tolerance following disturbance in an eastern deciduous forest. Canadian Journal of Forest Research. 39: 2460-2469.
- Royo, Alejandro A.; Bates, Ramona M.; Lacey, Elizabeth P. 2008. Demographic constraints in three populations of Lobelia boykinii, a rare wetland endemic. Journal of the Torrey Botanical Society. 135(2): 189-199.
- Royo, Alejandro A.; Carson, Walter P. 2008. Direct and indirect effects of a dense understory on tree seedling recruitment in temperate forests: habitat-mediated predation versus competition. Canadian Journal of Forest Research. 38: 1634-1645.
- Royo, A.A. 2008. P.A. Thomas and J. Packham: Ecology of woodlands and forests: Description, dynamics, and diversity [book review]. Landscape Ecology. 23(6): 755-756.
- Royo, Alejandro A.; Carson, Walter P. 2006. On the formation of dense understory layers in forests worldwide: consequences and implications for forest dynamics, biodiversity, and succession. Canadian Journal of Forest Research 36:1345-1362
- Comisky, Lauren; Royo, Alejandro A.; Carson, Walter P. 2005. Deer browsing creates rock refugia gardens on large boulders in the Allegheny National Forest, Pennsylvania. American Midland Naturalist. 154: 201-206.
- Banta, Joshua A.; Royo, Alejandro A.; Kirschbaum, Chad; Carson, Walter P. 2005. Plant communities growing on boulders in the Allegheny National Forest: Evidence for boulders as refugia from deer and as a bioassay of overbrowsing. Natural Areas Journal. 25(1): 10-18.
- Reinhart, Kurt O.; Royo, Alejandro; Van der Putten, Wim H.; Clay, Keith. 2005. Soil feedback and pathogen activity in Prunus serotina throughout its native range. Journal of Ecology 93:890-898
- Royo, Alejandro A.; Carson, Walter P. 2005. The herb community of a tropical forest in central Panama: dynamics and impact of mammalian herbivores. Oecologia
Other Publications by Alex Royo *
- Lacey, Elizabeth P.; Royo, Alejandro; Bates, Ramona; Derr, David. 2001. The role of population dynamic models in biogeographic studies: an illustration from a study of Lobelia boykinii, a rare species endemic to the Carolina Bays. Castanea. 66(1-2): 115-125.
*Due to policy or copyright restrictions, we are unable to provide full-text versions of these publications. Please check with your local library or Contact Alex Royo to inquire about reprints.