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As natural habitats become fragmented by human activities, animals must increasingly move through human-dominated systems, particularly agricultural landscapes. Mapping areas important for animal movement has therefore become a key part of conservation planning. Models of landscape connectivity are often parameterized using expert opinion and seldom distinguish between the risks and barriers presented by different crop types. Recent research, however, suggests different crop types, such as row crops and orchards, differ in the degree to which they facilitate or impede species movements. Like many mammalian carnivores, bobcats (Lynx rufus) are sensitive to fragmentation and loss of connectivity between habitat patches. We investigated how distinguishing between different agricultural land covers might change conclusions about the relative conservation importance of different land uses in a Mediterranean ecosystem. Bobcats moved relatively quickly in row crops but relatively slowly in orchards, at rates similar to those in natural habitats of woodlands and scrub. We found that parameterizing a connectivity model using empirical data on bobcat movements in agricultural lands and other land covers, instead of parameterizing the model using habitat suitability indices based on expert opinion, altered locations of predicted animal movement routes. These results emphasize that differentiating between types of agriculture can alter conservation planning outcomes., INTRODUCTION As landscapes are converted to human uses, the resulting habitat loss and fragmentation hinder the ability of animals to move between remaining habitat patches (Noss 1987; Saunders, et al., [...]

After planting an orchard, a grower must wait a couple of years before the trees bear fruit. Whether the trees are young and growing or mature and productive, orchard managers [...]

Seed orchards' parental reproductive success is often assessed through surveys of seed-and pollen-cone production (reproductive investment). Although the reliability of this approach has been questioned, its speed and ease made it the method of choice for providing approximate estimates for the genetic quality and quantity of seed orchard crops. In this study, reproductive investment data from various female and male phenotypic assessment methods from three seed orchards (lodgepole pine (Pinus contorta Dougl. ex. Loud. var. latifolia Engelm.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and western larch (Larix occidentalis Nutt.)) were compared with reproductive success estimates based on DNA fingerprinting and parentage analyses. The use of reproductive investment as a proxy to reproductive success on estimating seed crop's volume genetic worth and diversity (measured by effective number of parents) was evaluated. Regression analyses indicated that the phenotypic assessment methods reflect the true parental reproductive success and that estimates of seed-and pollen-cone volume production appear to be the most appropriate indicators of female and male reproductive success, respectively. Although the best combination of female-male survey methods produced inflated effective number of parents estimates, the genetic worth estimates were similar to those based on DNA, highlighting their robustness to fertility variation assessment. Resume: Le succes de reproduction des semenciers d'un verger a graines est souvent determine par des inventaires de production des cones seminiferes et polliniferes (investissement dans la reproduction). Quoique la fiabilite de cette approche ait ete remise en question, sa simplicite et sa rapidite en ont fait la methode de choix pour obtenir des estimations approximatives de la qualite genetique et du volume de la production semenciere des vergers a graines. Dans la presente etude, les auteurs ont compare les donnees relatives a l'investissement dans la reproduction obtenues par differentes me-thodes d'evaluation phenotypique de l'effort femelle et de l'effort male aux estimations de succes basees sur l'analyse des empreintes d'ADN et l'analyse de parente dans trois vergers a graines (pin tordu latifolie (Pinus contorta Dougl. ex. Loud. var. latifolia Engelm.), Douglas vert (Pseudotsuga menziesii (Mirb.) Franco) et meleze de l'Ouest (Larix occidentalis Nutt.)). L'emploi de l'investissement dans la reproduction comme indication du succes de reproduction afin d'estimer la valeur genetique du volume de la production semenciere et sa diversite (evaluee par le nombre effectif de parents) a aussi ete evalue. Les analyses de regression ont indique que les methodes d'evaluation phenotypique refletent le succes parental reel de reproduction et que les estimations du volume de production de cones seminiferes et polliniferes semblent etre les indicateurs les plus appropries du succes reproducteur femelle et male. Meme si la meilleure combinaison des methodes de determination de l'effort femelle et de l'effort male produisaient des estimations gonflees du nombre effectif de parents, les estimations de la valeur genetique etaient similaires a celles qui etaient basees sur l'ADN, mettant en evidence leur robustesse relativement a l'evaluation de la variation de la fertilite. [Traduit par la Redaction], Introduction Forest tree recurrent selection programs attain their goals through two distinctive streams, namely breeding and production. Breeding with its classical three steps, crosses, testing, and selection, leads to the [...]

Low soil [O.sub.2] levels have been shown to limit growth in pecan [Carya illinoinensis (Wangenh.) K. Koch] seedlings and may limit yield in mature trees. To assess changes in the gas-phase [O.sub.2] concentration in a pecan orchard soil in response to flood irrigations throughout a growing season, two types of [O.sub.2] sensor were field tested: a galvanic [O.sub.2] sensor and a spectrometer-coupled chemical sensor (FOXY sensor). Galvanic sensors, housed in diffusion chambers, were buried at four depths and a datalogger recorded continuous voltage output. The FOXY [O.sub.2] sensor was utilized as part of a mobile [O.sub.2] detection system to field analyze gas samples withdrawn periodically from buried diffusion chambers. The FOXY sensor was found to be unstable, however, and difficult to calibrate under conditions of changing temperature and humidity. Laboratory experiments simulating submersion of the galvanic sensor indicated that voltage outputs were comparable to the range observed in the field, but the absence of diurnal concentration fluctuations, typically found in soil measurements, provided a way to discriminate between normal and aberrant output. The responsiveness of the galvanic sensor and its capability to continuously gather hourly data makes it superior to methods dependent on manual sample collection. Galvanic sensors were adequately suited for long-term in situ use in agricultural soil when housed in appropriate diffusion chambers. Higher costs, limited access to diffusion chambers during flood periods, and high variability associated with manually collected data make the FOXY mobile [O.sub.2] detection system comparatively less optimal for use in agricultural settings. Abbreviations: FEP, fluorinated ethylene-propylene; FOXY, fiber optic oxygen sensor system; LPSRC, Leyendecker Plant Science Research Center; PVC, polyvinyl chloride.

To determine the effect of wheel traffic and two different management practices on soil compaction and its consequences on physical and chemical soil properties, we measured penetration resistance, water infiltration, bulk density, macroporosity, chemical mobility, air permeability, and soil strength in a conventional orchard (integrated fruit-production program) with bare (sprayed with herbicides) rows and an organic apple orchard with grassed rows. Resistance measurements were taken both within the tree row and the wheel track, down to a depth of 0.35 to 0.40 m. The results indicate that compaction is greater in the wheel tracks under both management methods. Compaction in the wheel track was higher under organic than conventional management. Organic management resulted in a higher macroporosity in both the row and the wheel-track than conventional management. The 'close-to-saturation' infiltration rate was significantly greater within the row of the organic orchard (0.06 m/h) compared with the row of the conventional orchard (0.02 m/h), and compared with the wheel tracks (0.01 m/h). The precompression stress value in the top 100 mm, a measure of the soil strength, was low on all sites. The chemical mobilities were 57 and 50% in the organic orchard, and 86 and 93% in the conventional orchard, respectively, for wheel track and row. Apart from the compaction in the wheel track of the organic orchard, physical and chemical soil characteristics were in a better condition compared with the conventional orchard. Additional keywords: penetrometer, infiltration, chemical mobility, precompression stress, wheel track., Introduction Intensive trafficking in orchards by heavy machinery can cause soil compaction. This can change the soil structure and pore system (Peng et al. 2004), both pore size distribution and [...]

Abstract We report the results from a field experiment in which we examined the spatial and temporal patterns of water uptake by a mature apple tree (Malus domestica Borkh., 'Splendour') [...]

California has more than 600,000 acres of almond orchards. At the beginning of each new year, these almond trees burst into bloom. That's when growers will need many millions of [...]

New lures that entice codling moths with the scent of food and a possible mate are available for use in monitoring this orchard pest and controlling it with carefully timed [...]

Soil compaction is studied by measuring water infiltration, microbial activity and organic matter content in a conventionally and organic-managed apple orchard. It is shown that organic methods brings higher macroporosity within the row and wheel-track compared to conventional management, and can be used to manage irrigation and fertilizer applications in a better way.