Clopyralid and Compost: Formulation and Mowing Effects on Herbicide Content of Grass Clippings

The presence of clopyralid, a selective broadleaf herbicide, in compost near Spokane, Washington in 2000 was attributed to grass clippings collected from area lawns and subsequently used as compost feedstock. A field study was conducted in 2001 to evaluate the effects of herbicide formulation and mowing practice on the clopyralid content of grass clippings. The objective was to develop guidelines that would limit the concentration of clopyralid in clippings, thereby reducing the amount of clopyralid entering the compost production stream. Clopyralid was applied to turfgrass as either a sprayable (S) or granular (G) formulation. Grass clippings were either collected in a bagging lawn mower and removed from the plots or returned into the plant canopy using a mulching mower designed to finely chop and disperse the leaf blades. Clippings were sampled for a period of ten weeks after application, and again in the summer of 2002, and analyzed for clopyralid content. Mowing treatment had no significant effect on clopyralid content of grass clippings. The S formulation resulted in higher concentration than the G at 4 hours after treatment (193 mg kg^?1 and 53 mg kg^?1, respectively). At 10 weeks after treatment (WAT), clopyralid concentration averaged 0.9 mg kg^?1, and cumulative recovery of clopyralid in grass clippings was 35% and 29% of the amount applied for the S and G formulations, respectively. By 56 and 98 WAT, clopyralid concentration in clippings was 0.06 and 0.02 mg kg^?1, respectively. Based on these results, and depending on feedstock dilution and composting conditions, a waiting period of up to one year after application of clopyralid could be necessary for treated grass clippings to be safely used as compost feedstock.     

Effect of Anaerobic Digestion and Application Method on the Presence and Survivability of <Emphasis Type="Italic">E. coli</Emphasis> and Fecal Coliforms in Dairy Waste Applied to Soil

Animal wastes are commonly used in a sustainable manner to fertilize crops. However, manures contain numerous pathogenic bacteria that can impact animal and human health. Treatment of animal waste by anaerobic digestion has the potential to reduce pathogen loading to land. This study was conducted to determine the fate of bacteria applied in raw and anaerobically digested dairy slurries that were broadcast and subsurface applied in a field of forage grasses. Digested slurry had significantly fewer indicator bacteria, Escherichia coli and fecal coliform at time of application. Anaerobic digestion did not increase the survivability of indicator bacteria. Waste treatment and application method did not affect the rate of bacteria die-off. There were fewer E. coli and fecal coliform at the end of each trial in the soils that received digested slurry. Anaerobic digestion of dairy waste has the potential to reduce pathogenic bacteria loading to cropland.     

The introgression of 2× 1EBN <Emphasis Type="Italic">Solanum</Emphasis> species into the cultivated potato using <Emphasis Type="Italic">Solanum verrucosum</Emphasis> as a bridge

Wild diploid Solanum species with an endosperm balance number (EBN) of one are a rich source of disease resistance, pest resistance, and tuber quality traits. They are not sexually compatible with 4× 4EBN or 2× 2EBN forms of the cultivated potato. In this study, the wild 2× 2EBN Mexican species S. verrucosum (ver) was used as a bridge species to access 2× 1EBN germplasm. Hybrids (V1) were created between ver as a female parent and the 1EBN species S. cardiophyllum, S. chancayense, S. commersonii, and S. trifidum. Most of the V1 hybrids were successfully crossed as females to cultivated 2× 2EBN clones. However, due to stylar barriers, reciprocal crosses were unsuccessful. Additional studies are underway to determine the effectiveness of ver as a bridge to introgress specific traits from 2× 1EBN germplasm into the cultivated potato.     

Invasion of artificial ponds in Doñana Natural Park,southwest Spain,by an exotic estuarine copepod

• 1. During a study of five artificial brackish ponds situated in Doñana Natural Park and the Guadalquivir delta between July 2001 and June 2002, a total of six copepod species (two calanoids, three cyclopoids and one harpacticoid) were recorded. All of them are typical of brackish or estuarine habitats.
• 2. The estuarine calanoid copepod Acartia tonsa (originally from North America) was present in all the ponds studied. This exotic species has been found previously in European estuaries, but has not previously been recorded from artificial wetlands.
• 3. Both the relative and absolute abundance of the species varied significantly among months and ponds. A. tonsa was most abundant during autumn and spring, while Calanipeda aquae‐dulcis was most abundant in summer. This seasonal pattern of the copepod community composition was different from that reported in studies from other European estuaries or wetlands.
• 4. The invasion by and dominance of A. tonsa in the area of Doñana Natural Park has important implications for the conservation of the diverse native zooplankton fauna in the natural marshes of the adjacent Doñana National Park, which includes endemic species.

Copyright © 2005 John Wiley & Sons, Ltd.     

A Critical Comparison of Typologies of Small-Scale Forestry in Baden-Württemberg Derived Using Single and Multiple Criteria

The paper presents a typology of small-scale forest owners in Baden-Württemberg based on multiple criteria and derived using multivariate cluster analysis of long-term accountancy network data. Four distinct types of landholders are identified based on a combination of structural, financial and biophysical data. These groups fit well with the present knowledge on small-scale forest owners in Baden-Württemberg. In addition, the members of each group display clear differences in attitudes towards forestry, giving further support for the validity of the grouping. A comparison is made of this typology and typologies derived using the single criteria of forestry region, forest size class, cutting volume, proportion of coniferous trees, forest income and main source of income. This comparison demonstrates the advantages of using cluster analysis to identify types of small-scale forest owners in south-west Germany. No matter whether structural, natural or financial data are assessed, the multiple criteria typology produced by cluster analysis provides the highest percentage of statistically significant distinctions between the medians of the groups identified. A typology based on the single criterion of ‘regions’ provides the second best fit and has the advantage of being simple to develop. A more detailed comparison between these two typologies, whereby the differences between groups were analysed based on the links between individual groups in respect to individual variables, also indicated that the multiple criteria typology was superior.

Climate change impact predictions on Pinus patula and Pinus tecunumanii populations in Mexico and Central America

Climate change is likely to have a negative impact on natural populations of Pinus patula and Pinus tecunumanii, two globally important tree species in plantation forestry. The objective of this work was to evaluate the impact of climate change on the persistence of the natural populations of these species at their actual locations in order to take appropriate conservation measurements. A common approach to assess the impact of climate change on species natural distributions is climate envelope modeling (CEM). CEMs suggest significant impacts of climate change on the natural distribution of the two pine species, but their predictions contain considerable uncertainty related to the adaptive ability of tree populations to withstand future climate conditions. We assessed the adaptive ability of the two pine species based on the evaluations of provenance trials and used the results of these field trials to validate CEM impact assessment studies on provenance collection sites in the wild. The two pine species performed well in a wide range of climates, including conditions that were recorded by CEM as unsuitable for natural pine occurrence. The climate conditions where the two pine species naturally occur are predicted to become in the future more similar to the present climate of some areas where they are successfully established in field trials. These findings suggest that these pine species are in their natural habitat better adapted to climate change than CEM predicts. For the most vulnerable species, P. tecunumanii, human disturbances such as fragmentation from urbanization and conversion to agriculture that are occurring today are more urgent threats requiring action compared to the threat from climate change.     

Assessing for genetic and environmental effects on ruminant feed quality in barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis>)

Grain samples from a combined intermediate and advanced stage barley breeding trial series, grown at two sites in two consecutive years were assessed for detailed grain quality and ruminant feed quality. The results indicated that there were significant genetic and environmental effects for “feed” traits as measured using grain hardness, acid detergent fibre (ADF), starch and in-sacco dry matter digestibility (ISDMD) assays. In addition, there was strong genotypic discrimination for the regressed feed performance traits, namely Net Energy (NE) and Average Daily Gain (ADG). There was considerable variation in genetic correlations for all traits based on variance from the cultivars used, sites or laboratory processing effects. There was a high level of heritability ranging from 89% to 88% for retention, 60% to 80% for protein and 56% to 68% for ADF. However, there were only low to moderate levels of heritability for the feed traits, with starch 30–39%, ISDMD 55–63%, ADF 56–68%, particle size 47–73%, 31–48% NE and ADG 44–51%. These results suggest that there were real differences in the feed performance of barleys and that selection for cattle feed quality is potentially a viable option for breeding programs.