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- Western Australia (11)
- Contents (4)
- Franklin Pierce Law Center (4)
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- TOC (4)
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- Iowa (3)
- Nature conservation (3)
- Reclaimed land (3)
- Trees (3)
- Vegetation management (3)
- Agroforestry (2)
- Agronomic traits (2)
- Archean (2)
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- Breeding systems (2)
- Climate change (2)
- Cost analysis (2)
- Crop yield (2)
- Eucalyptus (2)
- Gene expression (2)
- Heating degree days (2)
- Production possibilities (2)
- Revegetation (2)
- Revegetation plants (2)
- Soil conservation (2)
- Sorghum bicolor L. Moench (2)
- Wild plants (2)
Articles 61 - 73 of 73
Full-Text Articles in Physical Sciences and Mathematics
Estimates Of Quantitative Genetic Parameters M Iap2b(M) Random-Mating Sorghum Population, A. J. Maves, R. E. Atkins
Estimates Of Quantitative Genetic Parameters M Iap2b(M) Random-Mating Sorghum Population, A. J. Maves, R. E. Atkins
Journal of the Iowa Academy of Science: JIAS
Random-mating populations of sorghum [Sorghum bicolor (L.) Moench] are used extensively as germ plasm in the development of parental lines for hybrids. Populations improved by recurrent selection provide a useful source for the selection of superior parental lines. Our objective was to determine the effectiveness of mass selection for threshed-panicle weight by comparing the performance of lines (S1 families) chosen randomly from CO and C4 of sorghum population IAP2B. Sixty S1 families from each cycle were grown in five Iowa environments.
Four cycles of selection for panicle weight shifted the mean for grain yield favorably, and the range …
Heating Degree Days In Iowa Relative To Home Natural Gas Consumption, Conservation Efforts, And Long-Term Trends, Richard E. Carlson
Heating Degree Days In Iowa Relative To Home Natural Gas Consumption, Conservation Efforts, And Long-Term Trends, Richard E. Carlson
Journal of the Iowa Academy of Science: JIAS
A methodology is presented to assess the effectiveness of conservation efforts relative to home heating. Billing period heating degree days and natural gas consumption relationships are established for a typical household for nineteen heating seasons using simple linear regression. Associated correlations (r2 values) were greater than 0. 95 for nineteen different seasons. Regression coefficients (b0 and b1) were found to decrease with time indicating reduced natural gas consumption due to conservation efforts. Procedures are presented to illustrate dollar savings relative to conservation efforts using the regression relationships. Long-term trends for heating degree days at the Ames, …
Studies Of The Precambrian Geology Of Iowa: Part 1. The Otter Creek Layered Igneous Complex, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson
Studies Of The Precambrian Geology Of Iowa: Part 1. The Otter Creek Layered Igneous Complex, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson
Journal of the Iowa Academy of Science: JIAS
Rocks from a buried igneous body, herein called the Otter Creek layered igneous complex, were recovered by drilling in Archean rocks in northwestern Iowa. This complex consists of layers of ultramafic and mafic cumulate rocks, including bronzitite, harzburgite, dunite, gabbro, and anorthosite. These rocks have been subjected to low-grade metamorphism with a patagenesis including serpentine, chlorite, talc, uralitic amphiboles, magnetite, albite, epidote, sericite, and minor quartz and calcite. During its intrusion, the magma which gave rise to the layered body engulfed a large block of rock consisting of banded iron formation and thin lamprophyre dikes. Both the iron formation and …
Studies Of The Precambrian Geology Of Iowa: Part 2. The Matlock Keratophyre, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson
Studies Of The Precambrian Geology Of Iowa: Part 2. The Matlock Keratophyre, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson
Journal of the Iowa Academy of Science: JIAS
Felsic pyroclastic rock occurs in the Precambrian basement in northwestern Iowa. This rock was recovered by drilling and originally logged as rhyolite; however it is severely depleted in K2O, Rb, Ba, Cs, and other mobile elements and is more properly called keratophyre. The volcanic unit lies atop a layered mafic/ultramafic complex and contains xenoliths of gabbro apparently derived from the layered body. These xenoliths are severely altered and are composed of secondary hydrated and carbonated minerals. The gabbros are enriched in incompatible trace elements, whose abundance patterns complement those of the keratophyre. Trace element abundance patterns for the …
Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate
Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate
Journal of the Department of Agriculture, Western Australia, Series 4
Deep tillage overcomes compaction of sandy soils caused by movement of heavy machinery. Many experiments since 1981 have shown cereal yields improve as a result of deep tillage. However, the increased yield does not necessarily mean more profit when costs are taken into account. To determine the profitability of deep tillage farmers must consider its impact on other farm operations. A whole-farm analysis is needed to accurately determine the increase in profit resulting from deep tillage
Survey Of The Damage Caused To Trees By Goats, Steve Gherardi, Dick Mills, Tim Johnson
Survey Of The Damage Caused To Trees By Goats, Steve Gherardi, Dick Mills, Tim Johnson
Journal of the Department of Agriculture, Western Australia, Series 4
The damage that goats can cause to trees is one of the major problems associated with their farming in the agricultural areas of Australia. It is also considered one of the main hindrances to the development of the goat industry. The Department of Agriculture s Goat Industry Development Unit surveyed mohair and cashmere producers to determine the prevalence of tree damage and its extent and severity; why producers believed goats damaged trees; and how producers minimised or prevented this damage.
Remnant Vegetation On Farms Is A Valuable Resource, Richard Hobbs, Ken Wallace
Remnant Vegetation On Farms Is A Valuable Resource, Richard Hobbs, Ken Wallace
Journal of the Department of Agriculture, Western Australia, Series 4
Retention of native vegetation on farms is important both from an ecological and an economic point of view. Productivity in the paddocks ultimately will depend on the retention and replacement of trees and shrubs in the landscape. Remnants of native vegetation can play their part by helping to ensure the long-term viability of the agricultural system, as well as greatly enhancing the quality of life for those living on the land.
Trees And Livestock : A Productive Co-Existence, Richard Moore
Trees And Livestock : A Productive Co-Existence, Richard Moore
Journal of the Department of Agriculture, Western Australia, Series 4
Trees, as part of farming can help to combat land degradation problems and produce a good economic return from timber at the same time. For example, there is now clear evidence that planting trees can help combat salinity by lowering water-table levels. Trees can also substantially improve overall farm productivity by providing shelter for pastures and livestock. The challenge is to find practical and economical methods of integrating trees and farming. A combination of widely-spaced trees and livestock is one promising method. This article describes the benefits of this type of agroforestry to farmers, suitable locations and how to practice …
Planting Trees To Control Salinity, Nick Schofield, Phil Scott
Planting Trees To Control Salinity, Nick Schofield, Phil Scott
Journal of the Department of Agriculture, Western Australia, Series 4
Dense tree plantings covering at least 30 per cent of cleared land can lower groundwater levels by two metres or more in 10 years from the time of planting. This sizeable drop can be expected at sites receiving 700 to 800 mm of rain a year. Research by the Water Authority of Western Australia shows the most promising strategy when using trees is to put dense plantings on the discharge zone and on lower to midslopes. This strategy is successful where groundwaters contain less than 30,000 milligrams per litre total soluble salts (TSS).
This article discusses research in the 450 …
Windbreaks Prove Their Worth, Tim Negus
Windbreaks Prove Their Worth, Tim Negus
Journal of the Department of Agriculture, Western Australia, Series 4
Strong winds in the south-west of Western Australia in April 1991 carted tonnes of top soil from stubbles, over-grazed pastures, and recently prepared cropping land. However, where there were windbreaks, downwind protection into the paddock was up to 10 to 20 times the height of the windbreaks. On May 1, 1991, the author inspected farm land for damage from Narrogin to the Dongolocking area, to Harrismith, up the rabbit-proof fence to West Corrigin and back to Narrogin via Kweda. He found the extent of soil erosion varied, and that some tree species planted in windbreaks gave better protection than others
Narrow-Winged Seeder Points Reduce Water Erosion And Maintain Crop Yields, Kevin Bligh
Narrow-Winged Seeder Points Reduce Water Erosion And Maintain Crop Yields, Kevin Bligh
Journal of the Department of Agriculture, Western Australia, Series 4
Sowing crops without loosening the topsoil by tillage reduces water erosion. It can increase infiltration of rainfall into loamy soils, thereby reducing runoff and increasing potential crop yields. Crop yields were maintained after I1 seasons of seeding an Avon Valley loam near Beverley with minimum and no-tillage seeding operations. Infiltration increased significantly from 80 per cent of the 1983 growing-season rainfall under the traditional three tillage operations, to 87per cent under a single tillage operation using a combine seed drill. Infiltration increased further to 96 per cent under a no-tillage system using a triple^lisc drill. At Gnowangerup, 80 per cent …
Variable Quality Of Saltbush Seed Influences Establishment, Stephen Vlahos, Donald Nicholas, Clive Malcolm
Variable Quality Of Saltbush Seed Influences Establishment, Stephen Vlahos, Donald Nicholas, Clive Malcolm
Journal of the Department of Agriculture, Western Australia, Series 4
Farmers are using niche seeders to direct-seed saltbushes (Atriplex spp.) cheaply on large areas of salt affected land. While many factors influence successful establishment of these shrubs, fanners can control the quality of the seed they use. Too often, the lack of knowledge of saltbush seed quality has resulted in extremely poor establishment. The importance of seed quality is well recognized in the establishment of grain crops and pastures, but it is often overlooked when farmers buy or select seed of saltbush. If farmers know the quality of the seed they buy, they can make appropriate adjustments to the sowing …
Using Trees To Reclaim Land Lost To Saline Seeps, Department Of Agriculture And Food, Western Australia, Arthur Wright
Using Trees To Reclaim Land Lost To Saline Seeps, Department Of Agriculture And Food, Western Australia, Arthur Wright
Journal of the Department of Agriculture, Western Australia, Series 4
The National Soil Conservation Program (NSCP) has tapped the vigorous community support for landcare initiatives through its demonstration sites for reclaiming sandplain seeps in the Western Australian wheatbelt. The demonstrations, which use tree plantations to reclaim seeps, began in 1989. The sites are being keenly monitored by participating farmers and members of land conservation districts (LCDs).