Sue Rutman’s scientific contributions

A floristic and natural history account is provided for six eudicot families as part of the vascular plant flora of the contiguous protected areas of Organ Pipe Cactus National Monument, Cabeza Prieta National Wildlife Refuge, and the Tinajas Altas Region in southwestern Arizona. This portion of the flora includes Malpighiaceae, Malvaceae, Martyniaceae, Molluginaceae, Montiaceae, and Moraceae. Four species are not native, three of which are established as reproducing populations. This is the sixteenth contribution for this flora, published in Phytoneuron. These contributions are also available open access on the website of the University of Arizona Herbarium: http://cals.arizona.edu/ herbarium.

A floristic account is provided for the cactus family as part of the vascular plant flora of the contiguous protected areas of Organ Pipe Cactus National Monument, Cabeza Prieta National Wildlife Refuge, and the Tinajas Altas Region in the heart of the Sonoran Desert in southwestern Arizona. The modern native cactus flora includes 35 taxa in 12 genera, plus 2 non-native pricklypears that are not established in the flora area. The overall cactus flora including fossils and nonnatives totals 39 taxa in 13 genera: at least 17 taxa are represented by fossils recovered from packrat middens, two of which are no longer present in the flora area. This account includes selected synonyms, English, Spanish, and O’odham common names in when available, identification keys, brief descriptions, images, local and general distributional, natural history, and ethnobotanical information. This flora is specimen-based with selected specimens cited. A new combination is proposed: Echinocereus coccineus Engelmann subsp. santaritensis (W. Blum & Rutow) M.A. Baker. Echinomastus erectocentrus var. acunensis is treated as synonym of Sclerocactus johnsonii. Club chollas in the flora area previously called Grusonia kunzei and G. parishii are correctly shown to be G. wrightiana and G. kunzei, respectively. Cactus diversity in the flora area generally decreases from regions of higher and more predictable rainfall (east side of the flora area) to lower and less predictable rainfall (west side of the flora area). Sixteen taxa generally do not range westward from the flora area and five do not range eastward. Cylindropuntia, with 12 present-day taxa, is the most diverse cactus genus in the flora area as well as the Sonoran Desert. Also included is a discussion of convergent evolution of water-conserving adaptations in Peniocereus striatus and an African Euphorbia. This is the seventh contribution for this flora series published in Phytoneuron and available on the website of the University of Arizona Herbarium.

The contiguous Organ Pipe Cactus National Monument, Cabeza Prieta National Wildlife Refuge, and the Tinajas Altas region within the Sonoran Desert in southwestern Arizona have a vascular plant flora of 732 taxa (species, subspecies, varieties, and hybrids) in 420 genera and 94 families. Elevation and ecological diversity decrease from east (Organ Pipe) to west (Tinajas Altas) while aridity increases from east to west, all correlating with decreasing botanical diversity. Organ Pipe Cactus National Monument, which includes an ecologically isolated Sky Island of dwarfed woodland rising above actual desert, has a flora of 655 taxa in 395 genera and 93 families, of which 11 percent (72 species) are not native. Cabeza Prieta National Wildlife Refuge has a documented flora of 423 taxa in 266 genera and 63 families, of which 8.8 percent (37 species) are not native. The Tinajas Altas region has a flora of 228 taxa in 164 genera and 47 families, of which 5.3 pecent (12 species) are not native. Non-native species make up 10.7 percent (78 species) of the total flora of the three areas, but among these only 7 percent (52 species) are established in the flora area as reproducing populations. Six non-natives have become invasive species that pose serious threats to the native ecosystems: Sahara Mustard (Brassica tournefortii), Red Brome (Bromus madritensis subsp. rubens), Buffelgrass (Cenchrus ciliaris), Arabian and Mediterranean Grass (Schismus arabicus and S. barbatus), and Tamarisk (Tamarix chinensis).