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Secondary metabolites are defined as organic compounds that are not directly involved in the normal growth, development, and reproduction of an organism. They are widely believed to be responsible for interactions between the producing organism and its environment, with the producer avoiding their toxicities. In our experiments, however, none of the randomly selected 44 species representing different groups of plants and insects can avoid autotoxicity by its endogenous metabolites once made available. We coined the term endocides (endogenous biocides) to describe such metabolites that can poison or inhibit the parent via induced biosynthesis or external applications. Dosage-dependent endocides can selectively induce morphological mutations in the parent organism (e.g., shrubbiness/dwarfism, pleiocotyly, abnormal leaf morphogenesis, disturbed phyllotaxis, fasciated stems, and variegation in plants), inhibit its growth, development, and reproduction and cause death than non-closely related species. The propagule, as well as the organism itself contains or produces adequate endocides to kill itself.

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Mississippi forest landowners were surveyed to determine average discount rates or “hurdle rates”—the lowest rates of return they consider acceptable—for 3 nonforestry investments, and for 5, 15, and 25 yr forestry investments. The survey included 829 individuals who owned at least 20 ac of uncultivated land and had harvested timber during a recent 5 yr period; survey results are therefore oriented toward commercially active forest landowners. On average, the private nonindustrial forest landowners included in the survey expect timberland investments to earn higher rates of compound interest than relatively low-risk bank savings accounts and certificates of deposit. Relatively short-term (5 yr) timberland investments, however, have lower minimum rates of return than stocks, bonds, and mutual funds. With forestry investments, all else equal, Mississippi nonindustrial private forest landowners prefer shorter time periods—average hurdle rates in nominal terms before taxes were 8.0% for forestry investments lasting 5 yr, 11.3% for those lasting 15 yr, and 13.1% for those lasting 25 yr. Household income significantly influenced the lowest rate of return considered acceptable for 5 yr forestry investments—the rate was 9% for landowners with annual incomes above $50,000 and 7.4% for landowners with annual incomes below $50,000. On a hurdle rate basis, higher income private landowners in Mississippi generally find forestry investments lasting 15 yr to be competitive with stocks, bonds, and mutual funds. However, Mississippi landowners' 13.1% required rate of return for 25 yr forestry investments was higher than the rate considered acceptable for the other investments included in the survey. Reforestation tax incentives, cost-shares, and related public policies that reduce the front-end costs incurred by NIPF landowners tend to increase the projected rate of return for relatively long-term reforestation investments. South. J. Appl. For. 26(1):26–31.

On old-field sites in the South, oak stands may be established by direct seeding of acorns, or by planting seedlings. Planting seedlings costs approximately 2 1/2 times the cost of direct seeding on a per acre basis, and based on our study of overall costs and returns, we conclude that in most cases the additional costs of planting are not justified by the additional benefits. Direct seeding is therefore an economically viable alternative to planting, although success with seeding requires careful selection of species/site combinations and proper seed handling and storage. South. J. Appl. For. 16(1):34-40.

Forestry and environmental science students enrolled in a one credit hour freshman seminar course participated in a land management evaluation and water quality sampling excursion using canoes and water sampling equipment. The purpose of this assessment was to engage students with hands-on, field based education in order to foster connections to their chosen profession and natural resources. This culminated in a poster symposium of the experience. Broad competency areas for high impact practices in natural resource management were emphasized for learning. Students were engaged in the exercise and some commented that the project helped them develop a sense of place and forming connections within their peer group. Based on numerous other studies and this qualitative assessment, the use of water quality sampling and collection of real-world data can enhance student's perception of the teaching a learning effectiveness in natural resources management course.

Thousands of lower Manhattan residents sustained damage to their homes following the collapse of the Twin Towers on 11 September 2001. Respiratory outcomes have been reported in this population. We sought to describe patterns of home damage and cleaning practices in lower Manhattan and their impacts on respiratory outcomes among World Trade Center Health Registry (WTCHR) respondents. Data were derived from WTCHR Wave 1 (W1) (9/2003–11/2004) and Wave 2 (W2) (11/2006–12/2007) surveys. Outcomes of interest were respiratory symptoms (shortness of breath (SoB), wheezing, persistent chronic cough, upper respiratory symptoms (URS)) first occurring or worsening after 9/11 W1 and still present at W2 and respiratory diseases (asthma and chronic obstructive pulmonary disease (COPD)) first diagnosed after 9/11 W1 and present at W2. We performed descriptive statistics, multivariate logistic regression and geospatial analyses, controlling for demographics and other exposure variables. A total of 6447 residents were included. Mean age on 9/11 was 45.1 years (±15.1 years), 42% were male, 45% had ever smoked cigarettes, and 44% reported some or intense dust cloud exposure on 9/11. The presence of debris was associated with chronic cough (adjusted OR (aOR) = 1.56, CI: 1.12–2.17), and upper respiratory symptoms (aOR = 1.56, CI: 1.24–1.95). A heavy coating of dust was associated with increased shortness of breath (aOR = 1.65, CI: 1.24–2.18), wheezing (aOR = 1.43, CI: 1.03–1.97), and chronic cough (aOR = 1.59, CI: 1.09–2.28). Dusting or sweeping without water was the cleaning behavior associated with the largest number of respiratory outcomes, such as shortness of breath, wheezing, and URS. Lower Manhattan residents who suffered home damage following the 9/11 attacks were more likely to report respiratory symptoms and diseases compared to those who did not report home damage.