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A long-term horticultural experiment was conducted at two geographically distinct sites in southern Missouri in 2011-15 to study the response of American elderberry [Sambucus nigra (L.) subsp. canadensis (L.) Bolli] to various soil nitrogen (N) fertilizer levels. Three commercially available elderberry cultivars ('Adams II', 'Bob Gordon', and 'Wyldewood') were used. The three cultivars were each assigned to 16 of 48 four-plant plots in a completely randomized manner at each site. Four replications of four N fertilizer treatments (0, 56, 112, 169 kg-ha21 N) were randomly assigned to each cultivar's plots and applied for 4 years (2012-15). Fruit yields, plant growth, phenology, and pest incidence were determined each year. Fruit quality was assessed by analyzing basic juice characteristics as well as organic acids, carbohydrates, anthocyanins, and polyphenols from 2012-14 samples. Leaf tissue analysis determined the plants' mineral contents in 2012-14. Most factors evaluated were significantly affected by site, year, and cultivar, whereas the effects of N fertilizer treatment were less definitive. Fruit yields and plant growth increased with increasing N levels. For example, plants fertilized with 0, 56, 112, and 169 kg-ha21 N produced 123, 137, 155, and 161 fruiting cymes per plot (5.8 m2), respectively. The eriophyid mite incidence was higher on fertilized plants, but other pests were not influenced by the N treatment. Basic fruit juice characteristics (soluble solids, pH, titratable acidity, polyphenols) were not influenced by the N treatment, whereas total anthocyanins were statistically higher in unfertilized plants. Levels of organic acids and carbohydrates in juice varied statistically among N treatments, but patterns were difficult to discern. Leaf N concentrations were correlated with N fertilizer levels--2.75% N with the highest fertilizer level compared with 2.55% N in unfertilized plants. Leaf levels of most other macronutrients varied, but consistent patterns did not emerge, and none of the micronutrients was different among N treatments. Although elderberry plants responded positively to increased N fertilizer levels in terms of plant growth and fruit yield, genetics (cultivar) and environment (site, year) were more influential on most other experimental factors evaluated. [ABSTRACT FROM AUTHOR]

The notion that teacher education should emphasize high-leverage practice, which is research based, represents the complexity of the subject matter, bolsters teachers' understanding of student learning, is adaptable to different curricular circumstances, and can be mastered with regular use, has traction in scholarship. Nevertheless, how teacher educators might support high-leverage practice concurrently within programs and school institutions remains an open question. We suggest that investigating adolescents' thinking about complex historical concepts and conflicting evidence can amplify high-leverage social studies teaching practice by defining its criteria and strengthening some key representations, like eliciting students' ideas about the subject matter and scaffolding analytical reading. Yet school-institutional factors that devalue systematic investigation of students' thinking as a way to impact instruction may impede this amplification. Using activity theory, we discuss the implications of our findings for promoting ambitious pedagogy through social studies teacher education amidst constraining school climates.

Alley-cropping systems that pair economically important tree species with crop production in alleyways have the potential to diversify outputs and improve resource use efficiency. However, management practices are more complex because trees and crops have different nutrient requirements and access different depths in the soil profile. Foliar nutrient concentrations are often used to determine fertility plans for fruit and nut production orchards, but these recommendations may not be appropriate in integrated tree and crop production systems. This research describes foliar nutrient concentrations in three different tree species, red oak (Quercus rubra L.), pecan [Carya illinoinensis (Wangenh.) K. Koch], and black walnut (Juglans nigra L.), at an alley-cropping site in northwest Arkansas, USA from 2004 to 2012. Foliar nutrient concentrations did not differ in trees fertilized by poultry litter when compared to those receiving synthetic N fertilizer. Concentrations of nutrients changed over time in all three species, with Mg and Ca increasing and N, K, S, Fe, and Na decreasing as trees aged. A principal components analysis indicated that leaf nutrient levels in oak and pecan were much more similar to each other than to black walnut. Some of the foliar nutrient concentrations identified in this study were inconsistent with sufficiency ranges reported in fruit and nut production orchards. However, given the multiple aims of an alley-cropping system, these inconsistencies may not represent deficiencies in available nutrients for these tree species. [ABSTRACT FROM AUTHOR]

Describes rules for the use and interpretation of "verbally determinate ellipsis" involving the English verb group. Discussion covers: verbal determinacy and indeterminacy; verb group vs. verb phrase; the verb group as a five-part system; verb group echoing vs. auxiliary contrasting ellipsis; passive auxiliary; interpretation rules; stress placement and interpretation; and variants. (CB)