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Articles 38371 - 38400 of 39436
Full-Text Articles in Life Sciences
Nitrogenous Fertilisers For Cereal Production, M G. Mason
Nitrogenous Fertilisers For Cereal Production, M G. Mason
Journal of the Department of Agriculture, Western Australia, Series 4
Among the many factors influencing crop response to nitrogen applications, the most important are the season, soil type, paddock history, time of application and source of nitrogen. Before deciding whether to use nitrogen on a cereal crop, which source to use and at what rate, the farmer needs some understanding of how these factors work.
Food And Distribution Of Underyearling Brook And Rainbow Trout In Castle Lake, California, Wayne A. Wurtsbaugh, R. Brocksen, C. Goldman
Food And Distribution Of Underyearling Brook And Rainbow Trout In Castle Lake, California, Wayne A. Wurtsbaugh, R. Brocksen, C. Goldman
Watershed Sciences Faculty Publications
A difference was found in the summer distribution of underyearling brook trout, Salvelinus fontinalis (Mitchill), and planted rainbow trout, Salmo gairdneri Richardson, in Castle Lake, California. Brook trout underyearlings oriented to the bottom and were found primarily in shallow water on the eastern shore of the lake near springs. The rainbow trout underyearlings were more pelagic and were found in the littoral areas along the entire shoreline. Gravimetrically, the food eaten during the summer by brook trout underyearlings was 13% terrestrial, 11% limnetic, and 76% benthic. Rainbow trout ate 15% terrestrial, 15% limnetic, and 70% benthic food. In summer, rainbow …
Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner
Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner
Bulletin of the University of Nebraska State Museum (1924–2023)
The distribution and evolution of Late Cenozoic tapirs are discussed and the forms present in Nebraska are reported. Two new species are described from the Ogallala Pliocene of Nebraska, ?Tapirus johnsoni and ?T. simpsoni. Tapirs are known in Nebraska from the Early Oligocene through the Middle Pleistocene. The northern limit of the distribution of the tapirs contracts gradually southward in North America throughout the Tertiary, and even during the Pleistocene interglacials Nebraska must have been near the northern limit of their range.
Stratigraphic Occurrences Of Teleoceras With A New Kimballianspecies From Nebraska, Lloyd G. Tanner
Stratigraphic Occurrences Of Teleoceras With A New Kimballianspecies From Nebraska, Lloyd G. Tanner
Bulletin of the University of Nebraska State Museum (1924–2023)
Study of Teleoceras remains in the University of Nebraska State Museum indicates that this specialized, short-limbed rhinoceros inhabited the Central Great Plains from Early through Late Pliocene. Previously thought to have become extinct at the end of the middle Pliocene, this genus is now known from the very latest Pliocene. A new species, Teleoceras schultzi, is described from the Kimball Formation, Ogallala Group, Frontier County, Nebraska.
Summary Of 1975 Field Experiments With Advisers: "Rape Blackleg Disease Fungicide Trials", M J. Barbetti
Summary Of 1975 Field Experiments With Advisers: "Rape Blackleg Disease Fungicide Trials", M J. Barbetti
Experimental Summaries - Plant Research
During 1973 and 1974 a large range of fungicide spray and seed treatment schedules were tested. The 1973 results were, on the whole, not very encouraging, but the very early post-germination spray, two weeks after germination, did indicate a possible means of control. In view of the 1973 results, in the 1974 trials fungicidal sprays were applied early, and a new method of application of fungicide to the seed, known as "prilling" was used. Using fungicide seed prills and seedless fungicide prills the idea was to have the fungicide mixed with materials which dispersed upon wetting, so releasing and making …
Summary Of Trial Results - 1975, N. R. Mckeown
Summary Of Trial Results - 1975, N. R. Mckeown
Experimental Summaries - Plant Research
1. From September 1971 to late August 1974 there was a mean reduction of legume content in the medic pastures from 40 per cent to 22.0 per cent but the reduction at 7.4 sh/ha was to 31 per cent. The drop in woolly clover content on the volunteer pastures was closely similar. 2. In 1972, at 7.4 sheep/ha a difference in body weight of 7-9 kg rapidly developed in favour of sheep grazing barrel medic compared with sheep on volunteer pasture. This difference was maintained consistently throughout the trial. At lower stocking rates the differences were smaller and less consistent. …
Evaluation Of The Systemic Nematicide Phenamiphos To Control The Nematode Anguina Sp In Toxic Ryegrass Pasture, B A. Stynes
Evaluation Of The Systemic Nematicide Phenamiphos To Control The Nematode Anguina Sp In Toxic Ryegrass Pasture, B A. Stynes
Experimental Summaries - Plant Research
Field trials done in 1974 showed that phenamiphos could be used to control Anguina sp. and suggested that low rates may be effective with critical timing of applications. These possibilities were investigated in 1975. Locality - Katanning - F. Quartermaine and c. Butterworth. Gnowangerup - J. Griffith. Tables 1 and 2 show the absolute levels of nematodes in ryegrass seed and the density of nematodes per unit area of pasture after treatment with phenamiphos. All rates of nematicide reduced the level and density of nematodes; the highest rate being slightly more effective. The spray schedule including sprays in July and …
Summary Of 1974 Weed Control In Lupin Evaluations, J. G. Allen
Summary Of 1974 Weed Control In Lupin Evaluations, J. G. Allen
Experimental Summaries - Plant Research
Lupin Trials 1974 1. Herbicides x Depth of Seeding - There is no evidence of a herbicide x depth of seeding interaction in lupin plant numbers, at either Broomehill or Eradu. The lupin plants on the shallow sown plots were reported to be more effected by herbicides than on the deeper sown plots at Eradu. It is suggested that shallow seeding may be a factor in predisposing lupin crops to simazine damage particularly on sandy soils, however it has not been possible to demonstrate such on effect. 2. Herbicides x Time of Seeding - At two sites (Myrup, Namban) there …
1975 Evaluation Of New Subterranean Clover Cultivars, C. M. Francis
1975 Evaluation Of New Subterranean Clover Cultivars, C. M. Francis
Experimental Summaries - Plant Research
This year's trials have added little to the data already accumulated on the corssbreds 175,1 and 239.2 (Table 1). Higher seed yields at Merredin would have included some hard seed from the previous year. The lack of reliable data from the May sowings due to poor viability of some seed lines (including 175 and 239) grown at Medina was unfortunate. Data from Lake King is not yet available. Geraldton performed surprisingly well in the late sowings despite overall low seed yields. With late sowing its flowering date was within a few days of the crossbreds so that late sowing appears …
1975 Soil Fertility - Grain Lupins - Long Term Rotation Trials, Ian Rowland
1975 Soil Fertility - Grain Lupins - Long Term Rotation Trials, Ian Rowland
Experimental Summaries - Plant Research
Soil Fertility - Grain Lupins 75A4, 75BA6, 75E4, 75GE9, 75JE9, 75MT6, 75N028, 75WH9. Long Term. Rotation Trials W56H, 66M29, 67Cl3, 67N4, 68E5, 68SG5, 69GE20, 73SG16. Soil Fertility - Grain Lupins Use of the stage 4 lupin variety trials to assess the effect of a year of sweet grain lupins on a following cereal crop was continued. The 1974 variety trials contained a number of lupin varieties randomised with two standard wheat varieties. Also at two times of planting. Eight trials were selected: 74GE26 at Morawa, 74BA7 at Badgingarra, 74WH8 at Wongan Hills, 74N08 at Bolgart, 74A8 at Beverley, 74MT8 at …
Extracts From The Department Of Agriculture's Annual Report, 1974-75, Department Of Agriculture, Western Australia
Extracts From The Department Of Agriculture's Annual Report, 1974-75, Department Of Agriculture, Western Australia
Journal of the Department of Agriculture, Western Australia, Series 4
The Department of Agriculture's Annual Report for the year ended June 30, 1975, took the form of short reviews of selected activities of the Department during the year.
Some of these reviews are reprinted below to give an idea of the range of activities undertaken by the Department. A limited number of copies of the full report are available to interested organisations from the Department of Agriculture, Jarrah Road, South Perth, 6151.
In past years the Department's report has taken the form of a relatively detailed technical summary of the work of each Division. Because of the large volume of …
1975 Part 2 - Rate, Time And Frequency Of Nitrogen Application On Kikuyu, W. J. Cox
1975 Part 2 - Rate, Time And Frequency Of Nitrogen Application On Kikuyu, W. J. Cox
Experimental Summaries - Plant Research
J. Burton,, Hazelvale 74DE7. I. Dry Matter Production kg/ha/day tables - (No Spring '74 N) (Spring N 1974) Soil Properties March 10, 1975. Total N concentration % - Tables
1975 Trials On Doublegee, D J. Gilbey
1975 Trials On Doublegee, D J. Gilbey
Experimental Summaries - Plant Research
75A16, 75A17, 75C13, 75MO36, 75MO37, 75WH21, 75WH22. Biological control of doublegee.
1975 Clover Scorch, D. L. Chatel
1975 Clover Scorch, D. L. Chatel
Experimental Summaries - Plant Research
(Feb 1976) This report covers the three major clover scorch activities for the year: A) The tolerance screening at Denmark. B) The dry matter production in the second year of a mowing trial, in which clovers with and without scorch were compared the previous year. C) A summary of the first four years of a disease incidence survey - and an examination of some meteorological factors in relation to disease development. The first two were done jointly with Dr C.M. Francis. The following tentative hypotheses are advanced to explain the regional differences in the distribution of clover scorch: a) The …
1975 Lupin Diseases, P M. Wood
1975 Lupin Diseases, P M. Wood
Experimental Summaries - Plant Research
Sclerotinia stem rot, a fungal disease, is becoming increasingly important. This disease can attack the stem at any point from the stem base to the first laterals. Lodging can result if the canker is severe enough. Superficial cankers can disrupt sap flow resulting in poorly filled pods. The fungicide Benlate is used overseas to control Sclerotinia in bean plantings, Accordingly, a fungicide trial was planned to estimate yield losses resulting from Sclerotinia infection. A secondary aim was to examine any yield response which could be attributed to reported growth promoting properties of benomyl - 75MT33. Brown spot of lupins - …
1975 Field Experiments On Legume Seed Inoculation, D. L. Chatel
1975 Field Experiments On Legume Seed Inoculation, D. L. Chatel
Experimental Summaries - Plant Research
(January 1976) LIST OF EXPERIMENTS 1. The effect of cobalt and seed inoculation on Unicrop lupins. GREEN RANGE 2. The effect of cobalt and seed inoculation on Unicrop lupins. BRAMLEY RESEARCH STATION 3. The effect of cobalt and seed inoculation on Unicrop lupins. McALINDEN 4. The effect; of cobalt and seed inoculation on Unicrop lupins. CHOWERUP 5. The effect of cobalt and seed inoculation on Unicrop lupins. ALANO OKA 6. The effect of cobalt and seed inoculation on Unicrop lupins. LANCELIN 7. The effect of inoculation on Uni crop lupins. KATANNING 8. The effect of inoculation on Uni crop lupins. …
A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr
A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr
Masters Theses
Gross primary productivity, heterotrophic bacterial numbers, and net phytoplankton densities of seven ponds in Coles County, Illinois, were studied in relation to physical, chemical, and biological habitat variables (light intensity and duration, turbidity, water temperature, pH, dissolved oxygen, sulfur, nitrogen, phosphorus, production, bacteria, and phytoplankton). Ten observations were made for each pond (except where otherwise noted) from 17 June through 25 August 1974. Stepwise multiple linear regression analyses of the data were used in order to determine those environmental factors which were important in predicting (i.e., significantly correlated with) bacterial and phytoplankton densities, and production. A multiple linear regression equation …
Biological Inventory In Conjunction With The Las Vegas Wash Unit, Colorado River Basin Salinity Control Act Title Ii (P.L. 93-320), W. Glen Bradley, J. Scott Miller
Biological Inventory In Conjunction With The Las Vegas Wash Unit, Colorado River Basin Salinity Control Act Title Ii (P.L. 93-320), W. Glen Bradley, J. Scott Miller
Publications (WR)
The present report is a biological inventory in conjunction with the Las Vegas Wash Unit, Colorado River Basin Salinity Control Act, Title II. The boundaries of the project encompass sections of North Las Vegas, Las Vegas, East Las Vegas and areas along Las Vegas Wash extending to its drainage point in Las Vegas Bay in Lake Mead. Therefore, it encompasses a wide array of ecological situations and landscapes ranging from essentially natural to various stages of urban development. This biological inventory presents basic ecological classifications, descriptions of vegetation, lists of vascular plants and vertebrates known to occur in the area. …
Raising Wood Ducks, Richard L. Nelson
Raising Wood Ducks, Richard L. Nelson
Nebraska Game and Parks Commission: Publications
Numbered among Nature's most colorful creatures, wood ducks willingly accept a helping hand from man in establishing new homes. These birds adapt well to suitable habitat, and you can play an important part in bringing the wood duck to locations where they do not now nest. For groups or individuals who are willing to expend the effort necessary to undertake a wood duck restoration project anti see it to completion, it is an exceptional gift from today's generation to those of decades and centuries to come. Many areas in Nebraska provide suitable wood duck habitat, but do not have a …
1975 Experimental Programme With Lupins, G H. Walton
1975 Experimental Programme With Lupins, G H. Walton
Experimental Summaries - Plant Research
74MO10 - Pasture establishment under a lupin orop (Wheat crqp 1975). 75AL3 - 6 Time x 3 Rates x 2 Varieties x 2 Herbicide Factorial. 75B3 - Lupin Agronomy in High Rainfall Area. 75BA4 - Early planting of Unicrop lupin. 75GE4 - Polyculture of Wheat and Lupin. 75GE5 - Rate of seeding Unicrop - low rainfall site. 75JE4 - Time of planting x rate of seeding lupins. 74MO10 - Pasture establishment under a lupin crop (Wheat crop 1975). 75MO6 - Time of planting x rate of seeding with L. albus cv WB2. 75MO7 - Pasture establishment under lupin crops. 75MO12 …
Time And Rate, Comparative Fungicide, Fungicide Application Method Trial, Clover Scorch Economy Demonstrations, A Bokor
Experimental Summaries - Plant Research
Time and Rate Trial 75AL33 Comparative Fungicide Trial 75AL34. Fungicide Application Method Trial 75D8. Clover Scorch Economy Demonstrations 75AL35.
1975 Field Experiments And Cereal Disease Surveys, A. G. P. Brown
1975 Field Experiments And Cereal Disease Surveys, A. G. P. Brown
Experimental Summaries - Plant Research
1. Septoria disease of wheat - 75BA17. 2. Fungicide seed dressing on lupins 3. Cereal Disease survey - Table 7 - Zone l. Beverley R.S. B3 2. Badgingarra A2 3. Chapman Bl 4. Gibson A5 5. Merredin C3 6. Mt Barker A5 7. Newdegate B4 8. Salmon Gums C5 9. Wongan Hills B2 10. Woodgenellup A5 11. Chowerup A5 12. Neradup A5 13. W. Grass Patch B5 14. E. Salmon Gums C5 15. Mellewa Cl 16. Yuna Cl 17. N. Mingenew Bl 18. Mingenew Bl 19. Gairdner River A5 20. Jerramungup B5 21. Ravensthorpe B5 22. N. Kojonup A4 23. …
1975 Weed Control In Lupin Investigations, J M. Allen
1975 Weed Control In Lupin Investigations, J M. Allen
Experimental Summaries - Plant Research
1. The results with pre emergence herbicides confirm previous recommendations of simazine 1.25 kg/ha on heavy soil and diuron 1.25 kg/ha on light soils with the following modification. a) Simazine rates need to be increased to 3 kg/ha on very early (April) sovm crops in southern areas. b) Simazine has not damaged lupins in southern areas and where ryegrass is a major problem on sandy soils (i.e. Esperance) it is likely to give better responses than diuron. 2. As suspected in previous years simazine can by way of effective weed control produce a marked lupin vegetative response without any increase …
1975 Mn Drilled And Sprayed On Unicrop, J. W. Gartrell
1975 Mn Drilled And Sprayed On Unicrop, J. W. Gartrell
Experimental Summaries - Plant Research
75AL25 (with Trevenen) Mn Drilled and Sprayed on Unicrop, 75AL26, 75ES28, 785ES29, 75GE32, 75MO31, 75MO33, 75TS24, 75TS25.
1975 Phosphorus And Sulphur Group Results, J. W. Bowden, B. Scurr, R Lunt, M Baker
1975 Phosphorus And Sulphur Group Results, J. W. Bowden, B. Scurr, R Lunt, M Baker
Experimental Summaries - Plant Research
Stocking X Super Rate - 66M30, 68BR7. Residual Value of Superphosphate - 66 & 68LG1, 66ME3, 66NO7, 67NO11, 67NO5, 74GE2, 74MO7, 74MO8. Maintainance P X S Trials - 65A1, 65C5, 65N5, 67NO11, 68AL3, 68B1, 69AL2, 69AL3, 69E6, 69WH15. Miscellaneous trials - Rates and Methods of Super on Wheat Lupins and Clover 74LG5, 75A20 and 21; 75ES5, 6, and 7; 75GE6 and 7; 75JE7, 75JE5, 75KA3 and 4; 75LG4 and 7; 75LG26; 75MO9, 75MO28, 75NA4, 75NO5 and 6. High Rainfall Pasture Trials - 75AL4 and 5; 75AR3 and 4; 75BR11, 12, and 13; 75BY5, 6, and 8; 75BU8 and 10; 75DE2, …
1975 Pasture Species Investigations High Rainfall Area, D. A. Nicholas
1975 Pasture Species Investigations High Rainfall Area, D. A. Nicholas
Experimental Summaries - Plant Research
Contents - 1. Clover cultivar grazing trial - North Bannister - 68NA1. 2. Clover cultivars x red legged earth mite - Chowerup - 70BR16. 3. Pastures species x stocking rate - Denmark - 72D1. 4. Stocking rate and conservation for steer beef production - Mt. Barker Research Station - 71MT46. 5. Perennial versus annual grass grazing trial - Manjimup Research Station - 72MN5. 6. Trials in Association - Albany Regional Office. (i) Rate and time of fungicide on clover scorch - South Stirlings - 75AL33. (ii) Rate and types of fungicide on clover scorch - South Stirlings - 75AL34. (iii) …
1975 Part 1 - Rates And Times Of Potassium Applications On Lupins Cv Unicrop, W. J. Cox
1975 Part 1 - Rates And Times Of Potassium Applications On Lupins Cv Unicrop, W. J. Cox
Experimental Summaries - Plant Research
K McQueen - Eneabba - 75TS1 I. Soil analysis II. Plant counts III. Seasonal dry matter production g/20 plants IV. Grain yield kg/ha harvested November 7, 1975 V. K, Ca, Mg and N in plants (a) effect of time of sampling (b) Effect of plant part on K concentration VI. K Ca, Mg and N uptake
1975 South West Sub.Clover Root Rot - 1975 Cultivation Experiments, M J. Barbetti, G C. Macnish
1975 South West Sub.Clover Root Rot - 1975 Cultivation Experiments, M J. Barbetti, G C. Macnish
Experimental Summaries - Plant Research
Trials were established in 1975 in the South West of WA to investigate the effect of time of cultivation, and nitrogen application, upon the incidence and severity of both tap and lateral root rot subterranean clover. Nitrogen application had little in the way of consistent effects. Cultivation reduced the levels of both tap and lateral root rot in many instances. These effects were most obvious and consistent at about the end of May. Cultivation just prior to or just after the break of season were the best cultivation treatments. Cultivation does appear to show some promise as a means of …
1975 Drought Responses Of Wheat Cultivars - Environment Responses Of Subterranean Clover., R N. Weir
1975 Drought Responses Of Wheat Cultivars - Environment Responses Of Subterranean Clover., R N. Weir
Experimental Summaries - Plant Research
Environment responses of subterranean clover. Aim - To clarify the responses of four cultivars to temperature, vernalisation and photoperiod. Method - Dinninup, Midland B, Geraldton and Blackwood sub clover was grown in phytotron cabinets under 14 hour and 10 hour photoperiods and temperatures 10°c day/5°c night, l5/l0°c, 20/l5°C, 25/20°c. A seed vernalisation treatment of 6 weeks refrigeration of swelled seed was included. Dissections were made to observe first floral initiation and first flower production was noted. Conclusions - Higher temperatures either had no effect or delayed floral initiation, but accelerated flower development greatly from initiation to anthesis. Photoperiod and vernalisation …
Population Ecology, Desiccation, And Food Resources With Respect To Angle Of Substrate For Two Limpets, Collisella (Acmaea) Digitalis And Collisella (Acmaea) Scabra, Linda Susan Collins
Population Ecology, Desiccation, And Food Resources With Respect To Angle Of Substrate For Two Limpets, Collisella (Acmaea) Digitalis And Collisella (Acmaea) Scabra, Linda Susan Collins
University of the Pacific Theses and Dissertations
Two common limpets, Collis~ (Acmaea) digitalis and Collisella (Acmaea) scabra have overlapping distributions in the upper int.ertidal .spray zone. Haven (1971) found that Q. digitalis is more abundant on vertical surfaces while Q. scabra dominates horizontal surfaces. He assumed this preference to be due to differential abilities to withstand desiccation. In this study I report field work demonstrating a high correlation between the-ratio of abundance of Q. digitalis/ Q. scabra and angle of slope of substrate. Length (mm) of Q. scabra declines linearly with angle, but Q. digitalis shows no such trends. Results of laboratory measurements of angle of substrate …