A classification system is presented for the grasslands and shrublands of the mountainous western third of Montana. The classification utilizes the habitat type concept and is based upon potential natural vegetation. Data on plant species and environment from 580 relatively undisturbed stands were analyzed to form the classification. Twenty-nine habitat types occurring in 13 climax series are defined and described. A diagnostic key utilizing indicator plant species is provided for field identification of the habitat types. Vegetation composition, distribution, and environment of each habitat type are described in the text. Tables are provided for detailed comparisons. Management related information on forage productivity, composition changes with grazing, and range management practices is summarized for each type.

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A mobile platform was developed for measuring midday canopy photosynthetically active radiation (PAR) interception in orchards. The results presented are for almond (Prunus dulcis) and walnut (Juglans regia), but the mobile platform can be used in other orchard crops as well. The mobile platform is adjustable to accommodate orchard row spacing from 4.8 to 7.8 m and is equipped with a global positioning satellite (GPS) receiver and radar for positional assessment as well as three IR thermometers for measuring soil surface temperature. Data from the mobile platform are logged at 10 Hz and stored on a data logger. Custom software has been developed to process the data. The mobile platform was used extensively for mapping midday canopy PAR interception in almond and walnut orchards in 2009 and 2010. The mobile platform produced comparable results to those collected with a handheld light bar with the advantage of being able to cover much larger areas and compare these data to mechanically harvested yield data over the same area. For almond orchards, midday canopy PAR interception peaked at ≈70% at an orchard age of ≈12 years. For walnut orchards, midday canopy PAR interception continued to increase to ≈15 years of age and peaked at a level above 80%. The mobile platform was also able to follow seasonal development of midday canopy PAR interception in young and mature orchards. This technology has potential for evaluating new varieties in terms of productivity per unit PAR intercepted, in evaluating hand pruning or mechanical hedging practices in terms of impact on PAR interception/productivity as well as evaluating effectiveness of insect or disease management treatments. It also has potential as a reference point for grower self-assessment to evaluate orchard canopy development compared with other orchards of similar variety, spacing, etc. Finally, this technology could be used as ground truth referencing for remotely sensed data.

The findings of this study add to growing evidence that root growth in many ecosystems follows a unimodal curve with one marked flush of root growth in coordination with the initial leaf flush of the season. Root vertical distribution appeared to have greater plasticity than timing of root production in this system, with temperature and/or carbohydrate competition constraining the timing of root growth. Effects on root distribution can have serious impacts on trees, with shallow rooting having negative impacts in years with limited soil water or positive impacts in years with wet springs, and deep rooting having positive impacts on soil water mining from deeper soil layers but negative impacts in years with wet springs.

The parasite Cryptosporidium parvum represents a threat to livestock health and production, water quality and public health. Cattle are known to be significant reservoirs of C. parvum, but transmission routes are complex and recent studies have implicated the potential role of wildlife in parasite transmission to cattle and water sources. On the Orkney Isles, high densities of Greylag geese (Anser anser) cause widespread faecal contamination of cattle pastures, where cryptosporidiosis is known to be the main cause of neonatal calf diarrhoea and Cryptosporidium contamination frequently occurs in two reservoirs supplying Mainland Orkney’s public water. This study aimed to determine the Cryptosporidium species and subtypes present in geese and calves co-grazing on four farms surrounding two reservoirs on Mainland Orkney. Results indicated a high level of C. parvum prevalence in calves, geese and water samples. gp60 analysis illustrated that higher genotypic diversity was present in the goose population compared with calves, but did not yield sequence results for any of the water samples. It can be concluded that the high levels of C. parvum evident in calves, geese and water samples tested represents a significant risk to water quality and public health.