James R Malusa
- Research Scientist, SNRE
- Ph.D. Ecology and Evolutionary Biology
- University of Arizona, Tucson, Arizona, United States
- The phylogeny and water relations of pinyon pines in relation to the vicariance biogeography of the American southwest.
No activities entered.
PracticumRNR 594 (Spring 2017)
Plants Of The DesertECOL 414 (Summer I 2016)
Plants Of The DesertECOL 514 (Summer I 2016)
- Malusa, J. R., Felger, R., Broyles, B., & Van Devender, T. (2012). Flora of Tinajas Altas, Arizona - A century of botanical forays and forty thousand years of Neotoma chronicles. J. Bot. Res. Inst. Texas, 6(1), 157-257.More infoThis flora of the vascular plants of the Tinajas Altas region, within the Lower Colorado Valley subdivision of the SonoranDesert of southwestern Arizona, includes the present-day species as well as fossils recovered from packrat middens. Thevegetation and flora are dynamic, changing even now, and have changed dramatically during the past millennia, along withshifting climate and human presences. This is the first publication for any region of a comprehensive temporal flora andspans more than 43,000 years of plants inadvertently collected and curated by packrats (Neotoma spp.) and more recentlyby botanists. We document a present-day flora of 227 species in 175 genera and 46 families. We also document at least 119species in 96 genera and 36 families from the fossil record and among these fossils at least 28 species in 17 genera and 6families are no longer present in the region. The most diverse families, present-day and fossil taxa, are Asteraceae, Poaceae,Boraginaceae, Cactaceae, Brassicaceae, Fabaceae, Solanaceae, Euphorbiaceae, Polygonaceae, and Nyctaginaceae. The mostdiverse genera are Cryptantha, Ambrosia, and Eriogonum. There are 12 non-native species in the flora, representing only5.3% of the modern flora, but only Sahara mustard (Brassica tournefortii) and Arabian grass (Schismus arabicus) are likely tonegatively impact the native plants.The famous waterholes, the Tinajas Altas, were critical for desert travelers and prehistoric people. The Tinajas AltasMountains, in one of the most arid parts of North America, have one of the richest fossil records for Ice Age plants in theworld. The radiocarbon-dated plant assemblages provide a detailed record of dramatic changes in geographic ranges of speciesand the succession from Ice Age woodlands to modern desertscrub. Prior to 11,000 years ago in the middle and lateWisconsin, Ice Age woodlands with single-leaf pinyon (Pinus monophylla), California juniper (Juniperus californica), Utahjuniper (Juniperus osteosperma), Sonoran scrub oak (Quercus turbinella), and Joshua tree (Yucca brevifolia) were at TinajasAltas and elsewhere in Sonoran Desert lowlands. The earliest known creosotebush (Larrea divaricata) in North America,18,000 years before present, from a Tinajas Altas midden, was already the modern tetraploid Sonoran Desert race.The Tinajas Altas region encompasses 80,000 acres (32,375 hectares) adjoining the western margin of the CabezaPrieta National Wildlife Refuge and is within the Barry M. Goldwater Range. Scientific, cultural, and aesthetic values dictatethat the Tinajas Altas should receive increased attention and protection.
- Malusa, J. R., Halvorson, B., & Angell, D. (2003). Distribution of the Exotic Mustard Brassica tournefortii in the Mohawk Dunes and Mountains, Arizona. Desert Plants, 31-37.More infoAmple winter-spring rains in southwestern Arizona in early 200 I allowed us to map the range of the exotic Brassica tournefortii in the Mohawk Sand Dunes. The mustard has colonized habitat ranging from creosote flats to dune crests, but it is most successful along ephemeral watercourses, the base of north-facing dunes, and along roads. An estimated 80-90% of the Mohawk Dunes, in both the Mohawk Valley and San Cristobal Valley, are host to B. tournefortii, with only the southernmost portion of the dunes uncolonized. Outside of the dunes, the mustard was found largely along roads frequented by the Border Patrol.
- Malusa, J. R. (1992). Phylogeny and Biogeography of the Pinyon Pines (Pinus Subsect. Cembroides). Systematic Botany, 17(1), 42-66. doi:http://www.jstor.org/stable/2419064More infoDiscrete qualitative and continuous quantitative characters ("gap-coded") are usedin a parsimony analysis of the phylogenetic relationships of the pinyon pines. Cladograms constructedusing all the data (both discrete and continuous characters) are congruent with thoseconstructed with the continuous characters deleted from the data set. The continuous charactersadd resolution to clades not resolved by discrete qualitative characters.T he resulting phylogeny isthen used to examine Axelrod's hypothesis that a Late Tertiary shift in regional climate-theelimination of summer rains in the far western United States-affected the evolution of the regionalflora. The cladograms produced by this study are in agreement with the inferred climate changes,with the most recently derived pinyon taxa being those from regions of summer drought. Thephylogeny is also used to examine otherb iogeographic trends,s uch as a shiftt owardsw ider substratetolerance and patterns in character evolution, such as the evolution of fewer needles per fasciclein the taxa endemic to areas of summer drought.
- Malusa, J. R., Falk, D. A., Laing, L., & Gebow, B. (2012, May). Mapping Ecological Systems in Southeastern Arizona. In Biodiversity and management of the Madrean Archipelago III, USDA Forest Service Proceedings RMRS-P-67. 2013, 1-7.More infoBeginning in 2007 in and around the Huachuca Mountains, the Coronado National Forestand other partners have been mapping ecosystems at multiple scales. The approach has focused onidentifying land type associations (LTA), which represent the sum of bedrock and superficial geology,topography, elevation, potential and existing vegetation, soil properties, and local climatic variables.This mapping effort has been extended into the FireScape program, in which multiple partners utilizeecological land type mapping as a framework for fire planning across the Sky Island bioregion. Landtype association maps for the Catalina-Rincon mountains (available at www.azfirescape.org) areused for managing ecological units (e.g., mixed conifer on granitic soils) typically no smaller than athousand acres, and often much larger. Land type associations compliment raster-based sources ofinformation such as LANDFIRE. Not surprisingly, the success of the project depends on an accuratedepiction of vegetative and physical setting reality, not just interpretations of remote imagery. LTAsprovide an intuitive and informative
- Maghran, L. A., Falk, D. A., Malusa, J. R., & Archer, S. R. (2016, November). Resilience and recovery from two large fires in the Santa Catalina Mountains. AFE Southwest Conference. Tucson, AZ: Association for Fire Ecology (AFE).
- Black, C., Whittle, R., Malusa, J. R., Fehmi, J. S., & Reed, M. (2014, March). Vegetation Associations of Southwest Arizona. Celebrating the Sonoran Desert - A tri-national symposium. Ajo, Arizona: Tohono O'odham Nation.
- Malusa, J. R., & Sundt, P. (2015, April). Vegetation of the Barry M Goldwater Range - West. Technical Report Coop Agreement DACA87-05-H-0018. https://www.researchgate.net/publication/278967083_Vegetation_of_the_Barry_M_Goldwater_Range_West_Marine_Corps_Air_Station_-_Yuma_Arizona_2015More infoThe purpose of this Cooperative Agreement was to develop a comprehensive vegetation map for the Barry M. Goldwater Range West (BMGR West) under management by the Marine Corps Air Station Yuma (MCAS Yuma), Yuma, Arizona. The vegetation map will allow effective management of the vegetation communities on the BMGR West and also provide a baseline for ecosystem management. The vegetation survey and mapping effort was conducted in support of the Integrated Natural Resources Management Plan (INRMP) dated March 2007 prepared by MCAS Yuma under the Sikes Act Improvement Amendments of 1997.