Treesearch

In an operational trial, increasing the amount of nitrogen (N) applied to container longleaf pine seedlings by incorporating controlled release fertilizer (CRF) into the media improved seedling growth and quality. Compared with control seedlings that received 40 mg N, seedlings receiving 66 mg N through CRF supplemented with liquid fertilizer had needles that were 4 in (10 cm) longer as well as 42%, 84%, and 47% greater root collar diameter, shoot biomass, and root biomass, respectively. We use data from this study and other published sources to make general, practical guidelines concerning...

Carbon (C) and nitrogen (N) cycling within an open brush site, a sacaton (Sporobolus wrightii) grass and a mesquite (Prosopis velutina) grove, in the riparian zone was closely linked to the yearly litter N inputs. Yearly mesquite litter fall for 2 yr was remarkably similar and averaged 4.0 g N m-2 and 65 g C m-2 soil and resulted in higher soil C content compared to other riparian vegetation. The riparian soils held 7,000 metric tons more C than an adjacent nonriparian area suggesting the riparian zone processes result in a sink for atmospheric C. Water is essential for ecosystem function,...

We estimated diet composition of sympatric Mexican spotted (Strix occidentalis lucida, n = 7 pairs of owls) and great horned owls (Bubo virginianus, n = 4 pairs) in ponderosa pine (Pinus ponderosa) - Gambel oak (Quercus gambelii) forest, northern Arizona. Both species preyed on mammals, birds, and insects; great horned owls also ate lizards. Mammals dominated the diet of both species. Mammals comprised 63 and 62% of all prey items identified in diets of spotted and great horned owls, respectively, and 94 and 95% of prey biomass. Both species primarily preyed on a few groups of small...

This paper deals with diversity, classification, and capabilities of different sagebrush (Artemisia spp.) communities. Capabilities of sagebrush communities in terms of production, plant diversity, potential for ground cover and sage-grouse (Centrocercus urophasianus) habitat are discussed. Reaction to fire and relationships with introduced annuals are also discussed for some communities.

[First paragraph] In 1999-2000, stakeholders involved with efforts to create Las Cienegas National Conservation Area identified lands north of the designated National Conservation Area and Acquisition Planning District boundaries as important to protect as well. These lands, formerly known as the Missing Link and now known as the Cienega Corridor, represent over 50,000 acres of important wildlife habitat and corridors, open space, cultural and economic resources, and watershed for recharge of Tucson’s groundwater. The area is under imminent threat of development, however, because it lies...

The Chiricahua leopard frog (Rana chiricahuensis) was historically widespread in suitable habitat throughout its range. Reports of recent population declines led to inventories of Chiricahua leopard frog localities. Surveys reported here establish a new baseline of occurrence in the Galiuros: only two of 21 historical localities were found to be occupied in 2003. One of these sites may represent the only source population for the species in that mountain range. The species’ reduced occurrence in the Galiuros may reflect its situation elsewhere. To aid in tracking recovery action efficacy,...

Container production of hardwood seedlings requires larger cavities, more space, and the ability to easily sort seedlings (as compared to conifers) very early during the germination phase of production. This presentation demonstrates the most productive system, based upon past experience, to commercially produce container hardwoods. The container system of choice is called “Old Native Tube” or “Vic Pots” and was developed and manufactured in Australia. Seedling target sizes are 18 to 24 in (45 to 60 cm) in height and 5 to 7 mm root collar diameter (RCD).

Geographic information science (GIS) and field work were applied to extend Major Land Resource Area (MLRA) 41, Southeastern Arizona Basin and Range, from Arizona and New Mexico into Sonora and Chihuahua, Mexico. The result of this analysis is a tentative boundary line that delineates MLRA 41 for both the United States and Mexico based on elevation, soils, temperature, precipitation, and vegetation. This delineation will allow for a more effective linkage of research and increased availability of information across the international border.

The radical transformation of the Southwestern landscape over the last century has had multiple repercussions. It is our belief that it was confiscation of the Dilzhe’e (Tonto Apache) home country, combined with evolving control of the land by Federal agencies after 1905, as much as the wars of conquest, which caused the dissolution of traditional Dilzhe’e, practice(s) and associated wisdom. In support of that claim this short paper focuses on the personal experience of Dilzhe’e Elders of the Yavapai-Apache Nation.

The encinal savannas of the sub-mogollon southwestern United States are important for livestock grazing and wildlife habitat. Little data have been collected on the ecology of these Sierra Madrean types of woodland land areas, which makes management difficult. Obtaining information such as habitat preferences for selected wildlife species and livestock can be an important piece of information towards the characterization and management of these areas. Habitat preferences of deer and cottontail were determined from repeated measurements of fecal accumulations on a circular 0.01-acre-plot...