Urban landscape irrigation is becoming increasingly important from a resource management point of view. Significant water use savings may be achieved if landscape irrigation is based on reference evapotranspiration (ETo). This study measured landscape crop coefficients (KL) for landscapes that are comprised of different vegetation types and irrigation water quality differences affecting KL. The KL was determined from the ratio of actual evapotranspiration to the ETo calculated from the modified Penman-Monteith equation. Irrigation quantity was based on 100% replacement of ETo. The KL values were determined for the following landscape vegetation on a fine sandy loam: St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze.], a single shumard red oak (Quercus shumardii Buckl.), St. Augustinegrass plus red oak, native grasses [Muhlenbergia capillaries (Lam.) Trin. and Schizachyrium scoparium (Michx.) Nash], and native grasses plus Red Oak in both College Station (CS) and San Antonio (SA), TX. Soil was systematically placed into lysimeters containing a drainage system and soil moisture probes. Lysimeters (1136 L) were placed in-ground in a randomized complete block design with three blocks. Soil moisture measurements were made at 0- to 20-, 20- to 40-, and 40- to 60-cm depths. The KL was determined after a rainfall or irrigation event for periods of 2 to 5 days. During the combined growing seasons of 2007 and 2008, KL in SA increased from early, to mid, to late season. In CS, the KL was unaffected by plant treatment or season. The St. Augustinegrass treatment KL seasonally ranged from 0.45 to 0.62 in SA. In CS, soil sodium accumulation caused decreased KL. These results of KL for mixed-species landscapes on non-sodic sites trend toward seasonal values of 0.5 to 0.7 for irrigation decisions in southern Texas. Landscape coefficients can be used as a tool in irrigation decision-making, which could contribute to water savings in amenity landscapes.

Effective landscape management practices in urban landscapes must include an awareness of nutrient removal from soil caused by leaching, and these practices should be those least damaging to freshwaters. Annual mean dissolved organic carbon (DOC), dissolved organic nitrogen (DON), nitrate-N, ammonium-N, soluble phosphate, and bicarbonate concentrations and fluxes were quantified in leachate from landscapes planted with different urban horticultural types. Plot vegetation consisted of either a single species or mixed species. The experiment was conducted at two sites in Texas with significantly different irrigation water chemistry. At the two sites, plant species had a significant effect on PO43--P flux, and irrigation chemistry had a significant effect on all nutrient fluxes. There was an interaction between plant species and irrigation chemistry for PO43--P flux (P < 0.05) only. The relationship between bicarbonate and DOC flux at sites was stronger and significant (0.92; P < 0.05) at the site irrigated with Na-HCO3 municipal tap water than at the site irrigated with Ca-HCO3 municipal tap water (R2 = 0.76, P = 0.05). Type of irrigation water chemistry may result in lower plant water uptake resulting in increased nutrients lost to leachate.

Self-efficacy beliefs are defined as context-specific assessments of one's competence to perform specific tasks, influence one's efforts, persistence, and resilience to succeed in a given task. Such beliefs are important determinants when considering agricultural science teachers' subject matter knowledge, teaching comfort levels, and their likelihood for success in the classroom. The purpose of this study was to assess selected Texas pre-service agricultural science teachers' knowledge and comfort for teaching state-mandated general agricultural science and technology objectives. Selected pre-service agricultural science teachers representing four Texas teacher education programs responded. Respondents' summed knowledge and teaching comfort scores revealed perceptions of "adequacy" in seven of the eight general agricultural science and technology areas. However, they had low levels of knowledge and teaching comfort for the soils and soil formation objectives. A moderate positive association existed between overall knowledge and teaching comfort, supporting previous self-efficacy research. The findings indicated that pre-service teachers need additional preparation in the eight areas essential to every agricultural education classroom. Additional research in pre-service teacher self-efficacy, confidence, and competence is needed to identify causal factors affecting the less-than-desired levels of knowledge and teaching comfort for state-mandated general agricultural science and technology objectives.

Landscape water conservation methods and techniques contribute to managing water resources. Use of reference evapotranspiration (ETo) data and landscape coefficients is one method that needs further development. Local ETo data and actual plant water use were used to calculate plant factors (PFs) for three model landscapes composed of mixtures of turfgrass and shrubs. Model landscapes using a sandy loam soil included st. augustinegrass (Stenotaphrum secundatum), privet (Ligustrum japonicum), dwarf burford holly (Ilex cornuta ‘Burfordii Nana’), and dwarf yaupon holly (Ilex vomitoria ‘Nana’) at three ratios of turfgrass to shrub vegetative cover: 80:20, 50:50, and 20:80. Soil was placed into inground lysimeters in a complete randomized block design with soil moisture sensors and a drainage system. Lysimeters were irrigated with a sprinkler system, and water was applied at a rate of 100% replacement of ETo minus precipitation. Lysimeter soil leachate was collected from the drainage system and quantified. After 2 years, the PF of 20:80 and 50:50 turfgrass/shrub combination were greater than the PF of the 80:20 combination. Plant factors for the 80:20, 50:50, and 20:80 turfgrass:shrub combinations were 0.68, 0.97, and 1.01, respectively. There were no seasonal differences in PFs. Total growing season leachate depth over 2 years was 63.4, 30.7, and 12.6 mm for 80:20, 50:50, and 20:80, respectively. Further work on PFs should include other plant combinations, and evaluation in other climatic zones.

Aminocyclopyrachlor is an herbicide for broadleaf weed control that has recently come under scrutiny following reports of injury to landscape ornamentals across the upper Midwestern United States. This herbicide has been shown to provide excellent weed control in warm-season turfgrasses at much lower use rates than that used for cool-season turf, but data are lacking concerning its safety to landscape ornamentals in southern U.S. regions. Parallel studies were conducted in Dallas and Huntsville, TX, locations to evaluate off-target injury effects on sixteen ornamentals and trees commonly used in southern landscapes. In March 2012, just prior to the spring growth flush, aminocyclopyrachlor was applied to potted plants at 0, 0.5, 1, 2, or 4× rates as either as granular [0, 14, 28, 56, or 112 g ai·ha−1 (0.013, 0.03, 0.05, and 0.10 lbs ai·A−1)] or liquid [0, 11.2, 22.4, 44.8, or 89.6 g ai·ha−1 (0.01, 0.02, 0.04, 0.08 lbs ai·A−1)] formulations. For the next 8 weeks, plants were evaluated for injury to new growth. Injury was observed in 9 of the 16 species used, but was generally mild to moderate in nature. Species exhibiting the greatest sensitivity to aminocyclopyrachlor included loblolly pine (Pinus taeda), viburnum (Viburnum odoratissimum), nandina (Nandina domestica ‘Compacta’), and camellia (Camellia japonica). Extent of injury was not different between granular or liquid formulations, but was less severe at the Dallas location. Results of the study indicate sensitivity within some southern landscape ornamentals to aminocyclopyrachlor.