Life Sciences Commons^™

Notes On The Vegetation And Flora Of North Padre Island, Texas, E. Glenn Carls, Robert I. Lonard, Dennis B. Fenn

Biology Faculty Publications and Presentations

No abstract provided.

Woody Plants Of The Lower Rio Grande Valley, Texas, Robert I. Lonard, James H. Everitt, Frank W. Judd

Biology Faculty Publications and Presentations

Description of Common Vegetation of Lower Rio Grande Valley.

Esenbeckia Berlandieri (Rutaceae) Rediscovered In Extreme Southern Texas, Michael R. Heep, Robert I. Lonard

Biology Faculty Publications and Presentations

No abstract provided.

Sea Urchins From The Brazos Santiago Pass Jetty, South Padre Island, Richard R. Fairchild, Lazern O. Sorensen

Biology Faculty Publications and Presentations

Data on occurrence and distribution of sea urchins (Echinoidea) are presented for the Brazos Santiago Pass jetty on South Padre Island, Texas. Echinometra lucunter is recorded from the Texas coast.

Factors Influencing Cellulolytic Activity Of The Soil Fungus, Aspergillus Candidus, Jacobo Ortega, Ernest J. Baca

Biology Faculty Publications and Presentations

Effects of pH, incubation time, nitrogen source and carbohydrate source upon production of carboxymethyl cellulase by Aspergillus candidus grown in liquid medium were studied. Maximal cellulase activity per unit of protein occurred in culture fluids with a pH of 5.5, after 10 days of cultivation of the fungus. Ammonium nitrate supported the highest production of the enzyme. However, in the nitrogen-source test, highest accumulation of extracellular protein was found in fluids from cultures with urea as the nitrogen source. Cotton fibers produced the greatest gain in cellulase activity when the carbohydrate source was incremented from 0.5 to 1.0 percent. The …

Effects Of A Severe Freeze On Native Woody Plants In The Lower Rio Grande Valley, Texas, Robert I. Lonard, Frank W. Judd

Biology Faculty Publications and Presentations

The effects of a severe freeze in December, 1983 on the native plants of the lower Rio Grande Valley, Texas were determined for 75 species. Damage was initially assessed by examining leaves, apical meristems, and cambial tissues of stems. Initial assessments were confirmed by surveys in the spring when new leaves were present. Forty-three species were either undamaged or had only minor leaf damage. Twenty-two species with damaged leaves had intact apical meristems or showed evidence of damage for less than 10 cm below the apical meristem. Three species, Leucaena pulverulenta, Cordia boissieri, and Karwinskia humboldtiana, had more extensive damage, …

Habitat Selection Related To Resource Availability Among Cavity-Nesting Birds, Timothy Brush

Biology Faculty Publications and Presentations

Variation in snag species and abundance appeared to explain most of the habitat selection patterns observed in five cavity-nesting riparian species over a three-year period. All species except Ash-throated Flycatchers were most common in areas with cottonwood or willow snags, which have relatively soft wood and are preferred nest sites. Classification of habitats on the basis of nest-site characteristics was useful and should be considered in other habitat selection studies.

The Terrestrial Flora Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd

Biology Faculty Publications and Presentations

The primary aim of this work is to enable the user to identify the flowering plants of South Padre Island; however, it should be useful for identification of plants on other Texas barrier islands and on the Mexican barrier islands. We hope that the keys will aid teachers, students, coastal zone managers, and individuals conducting environmental impact assessments.

Phytogeography Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd

Biology Faculty Publications and Presentations

The phytogeographic affinities of the native flora of South Padre Island, Texas, are analyzed and the probable dispersal agent(s) for each species identified. The native flora consists of 99 species and 44% of the species also occur on the adjacent Texas mainland; 28% of the native species have tropical affinities. Only three species have probably dispersed from the island to the mainland. Two species may be endemic to Padre Island and the Tamaulipan barrier islands. Most of the tropical species have reached the island by oceanic drift, but birds are the most important dispersal agent for the native species. Man …

Cellulase Activities Of Soil Fungi, Jacobo Ortega

Biology Faculty Publications and Presentations

The cellulase activities of 8 isolates of fungi obtained from agricultural soils of Hidalgo County, TX were investigated by measuring the changes in the viscosity of a buffered solution of carboxymethylcellulose (CMC), produced by the fluids obtained from liquid cultures of these isolates. The change in the viscosity of the reaction mixture incubated at constant temperature (30 C) was measured with Cannon-Fenske routine viscometers. A buffered cellulase solution was used as a control.

Due to the variability that existed among the isolates investigated, it was possible to select active producers of cellulase with the method followed in this investigation. The …

Annotated Checklist Of The Flowering Plants Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd, Sammie L. Sides

Biology Faculty Publications and Presentations

This study catalogues the flowering plants of South Padre Island, Texas. A total of 207 species in 47 families is listed. The abundance and ecological distribution of each taxon are noted. Comparisons are made with the flora of Mustang Island, Texas. Ninety-three species, 96 genera and 36 families are common to both islands. Three families, Compositae, Gramineae and Leguminosae, contain large shares of the total number of species on both islands. Apparently, much of the floral diversity is due to the presence of a large number of species that are represented by small populations.

Reinstatement Of The Genus Tiquilia (Boraginaceae: Ehretioideae) And Descriptions Of Four New Species, Alfred Richardson

Biology Faculty Publications and Presentations

No abstract provided.

Recommended Vegetable Varieties For The Lower Rio Grande Valley Of Texas, J. B. Corns

Biology Faculty Publications and Presentations

No abstract provided.