scholarly journals Efficacy of Foliar Insecticides Against Potato Leafhopper, 1997

1998 ◽  
Vol 23 (1) ◽  
pp. 181-182
Author(s):  
R. R. Youngman ◽  
T. P. Kuhar ◽  
C. A. Laub
Keyword(s):  
Stainless Steel ◽  
Air Temperature ◽  
Weather Conditions ◽  
Post Treatment ◽  
Potato Leafhopper ◽  
Foliar Sprays ◽  
Untreated Check ◽  
Sweep Net ◽  
Spray Treatment

Abstract Ten insecticide treatments and an untreated check were evaluated against PLH nymphs and adults in a 4th-year stand of ‘Arrow’ alfalfa located in Montgomery Co., VA. Plots of 20 X 30 ft were arranged in a RCBD in each of four replications. PLH densities and stem ht were determined on 18 Jul in each plot prior to spray treatment. Post-treatment PLH densities and stem ht were sampled every 4 to 5 d in all plots through 11 Aug. PLH density was estimated using combined counts of nymphs and adults from 5 pendulum sweeps of a 15-inch-diam sweep net taken arbitrarily across the plot. Stem ht was determined by measuring the length of 2 stems per plot. All insecticide treatments were applied as foliar sprays on 18 Jul using a CO2 backpack sprayer. The backpack sprayer was equipped with 4, 8002VS stainless steel spray tips and calibrated to deliver 20 gpa at 40 psi. Weather conditions during application ranged from 85-90°F air temperature, clear skies, and minimal wind movement. A two-way ANOVA and LSD were used to analyze differences among treatments in PLH sweep-net counts, after (x + 0.5)1/2 transformation, and stem ht.

scholarly journals Potato Leafhopper Control In Alfalfa, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 195-196
Author(s):  
P. Kuhar Thomas ◽  
R. Youngman Roger ◽  
A. Laub Curtis
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Quality Analysis ◽  
Potato Leafhopper ◽  
Stem Height ◽  
Acid Detergent Fiber ◽  
Testing Laboratory ◽  
Untreated Check ◽  
Sweep Net ◽  
Spray Treatment

Abstract Three insecticide treatments were evaluated against PLH in a firstyear stand of ‘Haymaker ’ alfalfa located in Montgomery Co., VA. Plots of 24 X 40 ft were arranged in a RCBD with an untreated check in each of 4 replications. Mean alfalfa stem height and PLH density were estimated in each plot prior to spray treatment (21 Jul). Potato leafhopper density was estimated using combined counts of PLH nymphs and adults from 10 pendulum sweeps of a 15-inch diam sweep net taken arbitrarily across the plot. All insecticide treatments were applied as foliar sprays on 21 Jul using a CO2 backpack sprayer, delivering 20 gpa at 40 psi. Post-treatment alfalfa stem height and PLH densities were sampled every 3 to 4 d in each plot until harvest (14 Aug). Yields were determined from 60 ft2 swaths taken from each plot using a sickle-bar mower. Freshly mowed alfalfa was raked into a pile and weighed by hand using a milk scale to determine the wet wt at harvest. A 2.2-lb subsample of alfalfa was removed from each plot and dried at 131 to 140°F for 48 h to determine % dry matter. Forage samples were submitted to Virginia Tech Forage Testing Laboratory, Blacksburg, VA, for quality analysis, including % crude protein and % acid detergent fiber. A twoway ANOVA with Fisher ’s protected LSD was used to analyze differences among treatments in PLH sweep net counts (after [x + 0.5 ½ transformation), stem ht, dry matter yield, % crude protein, and % acid detergent fiber.

Barban Selectivity for Wild Oat in Wheat

Weed Science ◽  
1974 ◽  
Vol 22 (5) ◽  
pp. 476-480 ◽  
Author(s):  
Robert W. Neidermyer ◽  
John D. Nalewaja
Keyword(s):  
Triticum Aestivum ◽  
Air Temperature ◽  
Leaf Blade ◽  
Plant Morphology ◽  
Treatment Temperature ◽  
Avena Fatua ◽  
Post Treatment ◽  
Wild Oat ◽  
Wheat Growth ◽  
Wild Oats

The response of wheat (Triticum aestivum L.) and wild oat (Avena fatua L.) to barban (4-chloro-2-butynyl-m-chlorocarbanilate) was studied as influenced by plant morphology and air temperature after application. Growth of wheat and wild oat seedlings was reduced by barban at 0.3 μg and 0.6 μg applied to the first node, respectively. Barban application to the base and midpoint of the first leaf blade required a lower dose to reduce wild oat growth than wheat growth. Increased tillering occurred from barban injury to the main culm in wheat. Wheat and wild oat susceptibility to barban increased as the post-treatment temperature decreased from 32 to 10 C. Barban selectivity for wild oats in wheat was greater at 27 and 21 C than at 16 and 10 C.

Modelling pavement temperature for winter maintenance operations

2004 ◽  
Vol 31 (2) ◽  
pp. 369-378 ◽  
Author(s):  
Aly Sherif ◽  
Yasser Hassan
Keyword(s):  
Surface Temperature ◽  
Air Temperature ◽  
Negative Impact ◽  
Weather Conditions ◽  
Statistical Modelling ◽  
Dew Point ◽  
Road Maintenance ◽  
Winter Maintenance ◽  
Pavement Surface ◽  
Pavement Temperature

Road and highway maintenance is vital for the safety of citizens and for enabling emergency and security services to perform their essential functions. Accumulation of snow and (or) ice on the pavement surface during the wintertime substantially increases the risk of road crashes and can have negative impact on the economy of the region. Recently, road maintenance engineers have used pavement surface temperature as a guide to the application of deicers. Stations for road weather information systems (RWIS) have been installed across Europe and North America to collect data that can be used to predict weather conditions such as air temperature. Modelling pavement surface temperature as a function of such weather conditions (air temperature, dew point, relative humidity, and wind speed) can provide an additional component that is essential for winter maintenance operations. This paper uses data collected by RWIS stations at the City of Ottawa to device a procedure that maximizes the use of a data batch containing complete, partially complete, and unusable data and to study the relationship between the pavement surface temperature and weather variables. Statistical models were developed, where stepwise regression was first applied to eliminate those variables whose estimated coefficients are not statistically significant. The remaining variables were further examined according to their contribution to the criterion of best fit and their physical relationships to each other to eliminate multicollinearities. The models were further corrected for the autocorrelation in their error structures. The final version of the developed models may then be used as a part of the decision-making process for winter maintenance operations.Key words: winter maintenance, pavement temperature, statistical modelling, RWIS.

When, where and why do people encounter Australian brownsnakes (Pseudonaja textilis : Elapidae)?

1999 ◽  
Vol 26 (5) ◽  
pp. 675 ◽  
Author(s):  
P. B. Whitaker ◽  
R. Shine
Keyword(s):  
Air Temperature ◽  
Agricultural Land ◽  
New South ◽  
Habitat Type ◽  
Weather Conditions ◽  
Time Of Day ◽  
South Wales ◽  
Experienced Observer ◽  
Close Proximity ◽  
Species Ecology

Encounters between humans and dangerously venomous snakes put both participants at serious risk, so the determinants of such encounters warrant attention. Pseudonaja textilis is a large fast-moving elapid snake responsible for most snakebite fatalities in Australia. As part of a broad ecological study of this species in agricultural land near Leeton, New South Wales, we set out to identify factors influencing the probability that a human walking in farmland would come into close proximity to a brownsnake. Over a three-year period, we walked regular transects to quantify the number and rate of snake encounters, and the proportion of snakes above ground that could be seen. The rate of encounters depended upon a series of factors, including season, time of day, habitat type, weather conditions (wind and air temperature) and shade (light v. dark) of the observers’ clothing. Interactions between factors were also important: for example, the effect of air temperature on encounter probability differed with season and snake gender, and the effect of the observers’ shade of clothing differed with cloud cover. Remarkably, even a highly-experienced observer actually saw <25% of the telemetrically monitored snakes that were known to be active (i.e. above ground) nearby. This result reflects the snakes’ ability to evade people and to escape detection, even in the flat and sparsely vegetated study area. The proportion of snakes that were visible was influenced by the same kinds of factors as described above. Most of the factors biasing encounter rates are readily interpretable from information on other facets of the species’ ecology, and knowledge of these factors may facilitate safer coexistence between snakes and people.

scholarly journals Cars as next generation mobile weather stations: an initial investigation

2021 ◽  
Author(s):  
Giuliano Andrea Pagani ◽  
Marcel Molendijk ◽  
Jan Willem Noteboom
Keyword(s):  
Air Temperature ◽  
Weather Conditions ◽  
Ground Temperature ◽  
Warning Systems ◽  
Traction Control ◽  
The Future ◽  
Weather Stations ◽  
Temporal And Spatial ◽  
Positive Correlation Coefficient ◽  
Digital Equipment

&lt;p&gt;Modern automobiles are becoming more and more &amp;#8220;computers on the wheels&amp;#8221; having lots of digital equipment on board. Such equipment is both for the comfort and entertainment of the passengers and for their safety. Sensors play a key role in measuring several parameters of the car performance (e.g., traction control, anti-lock breaking system) and also environmental &amp;#160;parameters are observed directly (e.g., air temperature) or can be somehow inferred (e.g., precipitation via windscreen wipers activity/speed).&lt;/p&gt;&lt;p&gt;KNMI has been provided air temperature recorded every 10 minutes by thousands of vehicles driving in the Netherlands for the period January-October 2020. We have performed an initial exploratory temporal and spatial analysis to understand the most promising periods of the day and areas where sufficient data is available to perform a more thorough data analysis in the future. Furthermore, we have performed a correlation analysis between the outside temperature measured by cars and air and ground temperature observed by official weather station sensors placed at one location on the Dutch highways. The correlation results for three randomly selected days (with different weather conditions) show a good positive correlation coefficient ranging from 0.93 to 0.76 for car and station air temperature and from 0.91 to 0.67 for car temperature and station ground temperature.&lt;/p&gt;&lt;p&gt;This initial exploration paves the way to the use of (OEM) car data as (mobile) weather stations. We foresee in the future to use a combination of sensed variables from cars such as air temperature, traction control, windscreen wipers activity for example to improve observations of road slipperiness and related warning systems that are not restricted to Dutch highways only.&lt;/p&gt;

scholarly journals Identification of solar radiation effect on climatic indicators of the territory of Ukraine

2018 ◽  
Keyword(s):  
Solar Radiation ◽  
Solar Energy ◽  
Air Temperature ◽  
Temperature Regime ◽  
Atmospheric Pressure ◽  
Weather Conditions ◽  
Climatic Conditions ◽  
Practical Significance ◽  
Statistical Dependence ◽  
Physical Processes

Formulation of the problem. Understanding that solar energy is the main source of the majority of biological, chemical and physical processes on Earth, investigation of its influence on different climatic fields allows us to define the features of its space and hour fluctuations. To define radiation and temperature regime of the territory it is necessary to determine climatic features of the spreading surface, which absorbs and will transform solar energy. Considering the fact that modern climatic changes and their consequences cover all components of the system, today there is a problem of their further study for comprehension of atmospheric processes, modeling weather conditions on different territories depending on the properties. The purpose of the article is to determine interrelations between indexes of solar radiation (the Wolf's number) and air temperature, atmospheric pressure on the territory of Ukraine during 1965-2015, their change in space and time. Methods. Correlative method is one of the main methods of a statistical analysis which allows us to receive correlation coefficients of solar radiation variability indexes, air temperature, atmospheric pressure on the territory of the research. This technique estimates the extent of solar radiation influence on temperature regime of the territory and distribution of atmospheric pressure. Results. Coefficients of correlation, which characterize variability of solar radiation indexes, air temperature and atmospheric pressure on the explored territory have been received by means of statistical correlation analysis method. This technique allows us to estimate the degree and nature of solar radiation influence on a temperature regime of the territory and distribution of atmospheric pressure. It has been defined that direct correlative connection between indexes of solar radiation is characteristic of air temperature and atmospheric pressure fields. Significant statistical dependence between incoming solar radiation on the territory of Ukraine and atmospheric pressure has been noted during the spring and autumn periods mainly at the majority of stations. Between indexes of solar radiation and air temperature the inverse correlative connection in winter will be transformed to a direct connection during the spring and summer periods. Scientific novelty and practical significance. Physical processes, which happen in the atmosphere, are characterized by complex interrelations. For further research it is important to define solar radiation value and the extent of influence on climatic conditions.

scholarly journals Sea surface temperature variations in the south-eastern BalticSea in 1960–2015

Baltica ◽  
2018 ◽  
Vol 30 (2) ◽  
pp. 75-85 ◽  
Author(s):  
Viktorija Rukšėnienė ◽  
Inga Dailidienė ◽  
Loreta Kelpšaitė-Rimkienė ◽  
Tarmo Soomere
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Air Temperature ◽  
Weather Conditions ◽  
Sea Surface ◽  
South Eastern ◽  
Air Temperatures ◽  
Joint Application ◽  
Open Sea ◽  
And Cluster Analysis

This study focuses on time scales and spatial variations of interrelations between average weather conditions and sea surface temperature (SST), and long-term changes in the SST in south-eastern Baltic Sea. The analysis relies on SST samples measured in situ four times a year in up to 17 open sea monitoring stations in Lithuanian waters in 1960–2015. A joint application of non-metric multi-dimensional scaling and cluster analysis reveals four distinct SST regimes and associated sub-regions in the study area. The increase in SST has occurred during both winter and summer seasons in 1960–2015 whereas the switch from relatively warm summer to colder autumn temperatures has been shifted by 4–6 weeks over this time in all sub-regions. The annual average air temperature and SST have increased by 0.03°C yr–1 and 0.02°C yr–1, respectively, from 1960 till 2015. These data are compared with air temperatures measured in coastal meteorological stations and averaged over time intervals from 1 to 9 weeks. Statistically significant positive correlation exists between the SST and the average air temperature. This correlation is strongest for the averaging interval of 35 days.

Hönnun og virkni léttra gróðurþaka við íslenskar aðstæður

2018 ◽  
Vol 24 ◽  
pp. 31-41
Author(s):  
Halla Einarsdóttir ◽  
Ágúst Elí Ágústsson ◽  
Hrund Ólöf Andradóttir ◽  
Magnús Bjarklind ◽  
Reynir Sævarsson
Keyword(s):  
Air Temperature ◽  
Water Retention ◽  
Center Of Mass ◽  
Weather Conditions ◽  
Green Roofs ◽  
Early Summer ◽  
Successful Design ◽  
Peak Runoff ◽  
Local Materials ◽  
Grass Turf

Green roofs are increasingly being installed cities in Europe as a part of sustainable stormwater systems. The goal of this research was to assess the hydrological efficiency of different configurations of extensive green roofs in Iceland and present suggestions for successful design of such roofs based on local materials and weather conditions. International literature and best design practices were reviewed. Runoff from five test roofs was monitored for 11 months, in conjunction with snowdepth, rainfall, wind and air temperature. Green roof water retention measured highest 85% in June and July in accordance with other studies in cold climates. Water retention measured, however, somewhat lower during the winter (<20%). Significant delay of runoff's center of mass and lowering of peak runoff was measured in all green roofs except during the largest runoff events. Average event water retention was correlated to air temperature, cumulative rain, rain 14 days before event and wind speed 7 days before event. Roofs with moss and sedum turf demonstrated good hydrological efficiency, good appearance and needed little maintenance. Grass turf roofs retained slighlty more water, but were less drought resistant and looked poorly during early summer. Wild, water resistent plants like moss and sedum performed better overall.

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