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Description And Key To The Identification Of Grasses In South-Western Australia, J G. Paterson Apr 1992

Description And Key To The Identification Of Grasses In South-Western Australia, J G. Paterson

Bulletins 4000 -

The grasses comprise one of the world's largest families of flowering plants, with about 670 groups or genera containing over 9000 individual types or species distributed throughout the world. Over 130 groups have been recorded in Western Australia but probable that the list is far from complete. About one third of these have been introduced from overseas.


A Survey Of Mucilaginous Testa In Chamaesyce, Martha S. Jordan, W. John Hayden Apr 1992

A Survey Of Mucilaginous Testa In Chamaesyce, Martha S. Jordan, W. John Hayden

Biology Faculty Publications

Seeds of Chamaesyce were studied for presence of mucilaginous testa. Samples were selected to represent all major systematic sections within the genus. Observations were made with a dissecting microscope following brief hydration of seeds; additional SEM observations of both intact and fractured dry seeds were made for selected species. With few exceptions, most of Boissier's subsections test positively for seed mucilage; however, mucilage is generally absent in subsections Gymnadeniae and "Sclerophyllae", for which absence of mucilage is regarded as secondary loss from mucilagionus ancestors. Although mucilage production is associated with a well-defined subepidermal layer of macroesclereids, it is …


Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer Apr 1992

Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer

Biological Sciences Theses & Dissertations

Four experiments were performed to determine the ability of marine higher fungi to grow in and degrade crude oil. Eight species, previously determined to be hydrocarbonoclastic, were grown in artificial sea water medium (ASM) and southern Louisiana crude oil. The dry mycelial weights were measured and consumption of crude oil was measured gravimetrically. The two species with the best growth, Corollospora maritima and Zalerion maritimum, were grown in ASM containing crude oil spiked with three known hydrocarbons. To this was added glucose (0.15%) and incubated 49 days to test for possible cometabolism of hydrocarbons. Hydrocarbons remaining in the growth …


The Prairie Naturalist Volume 24, No.1 March 1992 Mar 1992

The Prairie Naturalist Volume 24, No.1 March 1992

The Prairie Naturalist

HABITAT CONSERVATION FOR NESTING LEAST TERNS AND PIPING PLOVERS ON THE PLATTE RIVER, NEBRASKA ▪ J. W. Ziewitz, J. G. Sidle, and J. J. Dinan

DIURNAL FLIGHT TIME OF WINTERING CANADA GEESE: CONSIDERATION OF REFUGES AND FLIGHT ENERGETICS ▪ J. E. Austin and D. D. Humburg

MYCOTOXIN OCCURRENCE IN WASTE FIELD CORN AND INGESTA OF WILD GEESE IN THE NORTHERN GREAT PLAINS ▪ K. F. Higgins, R. M. Barta, R. G. Neiger, G. E. Rottinghaus, and R. I. Sterry

NOTES

Cost of Nest Reuse by Western Kingbirds ▪ T. M. Bergin

A New Record for Falcate Spurge in the Midwest …


Nebline, March 1992 Mar 1992

Nebline, March 1992

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Ag Update: Agricultural News & Events

Home Extension News

On-the-Grow: Horticulture News & Recommendations

The Cloverline: 4-H News and Events

Extension Calendar

and other extension news


Chemical, Biological And Machinery Aids For Quality Haymaking, Michael Collins Feb 1992

Chemical, Biological And Machinery Aids For Quality Haymaking, Michael Collins

Kentucky Alfalfa and Stored Forage Conference

Hay and pasture crops are critical to Kentucky Agriculture and to that of the entire temperate region of the US. The sale of cattle, calves and dairy products provide 29% of Kentucky's farm income compared with 23% for tobacco. Beef cow-calf enterprises comprise the majority of cattle numbers in the state, however, dairy production is also significant. A substantial horse industry exists in Kentucky which is an excellent market for high quality alfalfa hay. At present a substantial amount of alfalfa for horse feeding in the state is imported.


Foreword [1992], Garry D. Lacefield Feb 1992

Foreword [1992], Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

This is the front matter of the proceedings.


Nebline, February 1992 Feb 1992

Nebline, February 1992

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Ag Update: Agricultural News & Events

Home Extension News

On-the-Grow: Horticulture News & Recommendations

The Cloverline: 4-H News and Events

Extension Calendar

and other extension news


Central Crops And Soils Research Station Highmore, South Dakota: Annual Progress Report, 1991, Agricultural Experiment Station, Plant Science Department Feb 1992

Central Crops And Soils Research Station Highmore, South Dakota: Annual Progress Report, 1991, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1991 progress report for the Central Crops and Soils Research Station at Highmore, South Dakota State College. This document represents the research conducted at the Station during the 1991 crop season including: weather data, alfalfa cultivar yield test, nitrogen and phosphorus fertilization of cool season grass, the use of soil tests for nitrogen application for corn, small grain trials, wheat breeding, oat research, soybean research, corn breeding, weed control research, crop evaluations, grain sorghum and corn herbicide demonstrations.


Nonglandular Trichomes Of Californian And Hawaiian Tarweeds, Andrew A. Maclachlan, Sherwin Carlquist Jan 1992

Nonglandular Trichomes Of Californian And Hawaiian Tarweeds, Andrew A. Maclachlan, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

The purpose of this paper was to demonstrate the diversity in nonglandular trichome morphology of tarweeds at the ultrastructural level, and to propose categories for the morphologies reported for such trichomes. Using light and scanning electron microscopy (SEM), the authors surveyed 31 species of II genera of tarweeds from California and three genera of tarweeds from Hawaii. Trichome cell wall thickness in the Californian species ranged from 1 to 6 ~μm, whereas in the Hawaiian species trichome cell wall thickness ranged from 1 to 14 ~μm. Based on their surface appearance using SEM, trichomes were grouped into four categories: grooved; …


Fire In A Riparian Shrub Community: Postburn Water Relations In The Tamarix-Salix Association Along The Lower Colorado River, S. D. Smith, D. E. Busch Jan 1992

Fire In A Riparian Shrub Community: Postburn Water Relations In The Tamarix-Salix Association Along The Lower Colorado River, S. D. Smith, D. E. Busch

Life Sciences Faculty Research

Higher water potentials in recovering burned salt-cedar (Tamarix ramosissima) relative to unburned plants and the opposite situation in willow (Salix gooddingii) provide evidence that postfire water stress is reduced in the former but not the latter. Similarly, diurnal patterns of stomatal conductance in these taxa are consistent with the existence of more vigor in burned salt-cedar than willow. Plots of water potential and transpiration demonstrate that hydraulic efficiencies may contribute to differences in fire recovery.


Wood Anatomy Of Lamiaceae. A Survey, With Comments On Vascular And Vasicentric Tracheids, Sherwin Carlquist Jan 1992

Wood Anatomy Of Lamiaceae. A Survey, With Comments On Vascular And Vasicentric Tracheids, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Quantitative and qualitative data are presented for 44 collections representing 42 species in 27 genera. Lamiaceae basically have: vessels with simple perforation plates; vessel-to-vessel pitting alternate; imperforate tracheary elements all libriform fibers, fibers commonly septate; axial parenchyma scanty vasicentric; rays Heterogeneous Type IIB. These features ally Lamiaceae closely with Verbenaceae. In addition to the Mesomorphy ratio (based on vessel element dimensions), features that indicate wood xeromorphy in Lamiaceae, in probable increasing order of importance are: presence of indistinct to marked growth rings; presence of helical thickenings in vessels; presence of vasicentric or vascular tracheids; presence of vessel groups averaging three …


An Updated Phylogenetic Classification Of The Flowering Plants, Robert F. Thorne Jan 1992

An Updated Phylogenetic Classification Of The Flowering Plants, Robert F. Thorne

Aliso: A Journal of Systematic and Floristic Botany

This update of my classification of the flowering plants, or Angiospermae, is based upon about 800 pertinent books, monographs, and other botanical papers published since my last synopsis appeared in the Nordic Journal of Science in 1983. Also I have narrowed my family- and ordinal-gap concepts to bring acceptance of family and ordinal limits more in line with those of current taxonomists. This new information and the shift in my phylogenetic philosophy have caused significant changes in my interpretation of relationships and numbers and content of taxa. Also the ending "-anae" has been accepted for superorders in place in the …


Plant Species Disjunctions, Daniel J. Crawford, Nam Sook Lee, Tod F. Stuessy Jan 1992

Plant Species Disjunctions, Daniel J. Crawford, Nam Sook Lee, Tod F. Stuessy

Aliso: A Journal of Systematic and Floristic Botany

The use of molecular data in the study of plant species disjunctions is reviewed and evaluated. The major reason for employing molecular information is to estimate genetic divergence between morphologically similar disjunct species. Flavonoid chemistry offers few advantages over morphology because it is difficult, if not impossible, to infer genetic divergence from the arrays of flavonoid compounds sequestered by two species. Also, flavonoids can, like morphological characters, undergo stasis. Rather direct evidence for this comes from the fact that extant and fossil species may have identical or nearly identical flavonoids. Enzyme electrophoresis is useful for estimating divergence between disjunct species …


A Revision Of The Allium Fimbriatum (Alliaceae) Complex, Dale W. Mcneal Jan 1992

A Revision Of The Allium Fimbriatum (Alliaceae) Complex, Dale W. Mcneal

Aliso: A Journal of Systematic and Floristic Botany

Allium fimbriatum in California and northern Baja California causes frequent difficulty in identification. The species, as defined by Ownbey, comprises nine varieties and is characterized by great morphologic diversity. No single character or suite of characters separates this species from others in the A. sanbornii alliance. This investigation was undertaken to survey the large number of herbarium specimens that have accumulated since Ownbey's study and to observe all of the taxa in the field or garden, something not accomplished by Ownbey. Orientation of the perianth segments, visible only in living material, along with shape and presence or absence of denticulation, …


Insect Problems Encountered By The Firewood Gatherer, Jay B. Karren Jan 1992

Insect Problems Encountered By The Firewood Gatherer, Jay B. Karren

All Archived Publications

No abstract provided.


Blackhorned Pine Borers, Jay B. Karren Jan 1992

Blackhorned Pine Borers, Jay B. Karren

All Archived Publications

No abstract provided.


Wood Anatomy Of Hedyosmum (Chloranthaceae) And The Tracheid-Vessel Element Transition, Sherwin Carlquist Jan 1992

Wood Anatomy Of Hedyosmum (Chloranthaceae) And The Tracheid-Vessel Element Transition, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Qualitative and quantitative data are presented for 22 collections of 14 species of Hedyosmum. Wood of the genus is primitive in its notably long scalariform perforation plates; scalariform lateral wall pitting of vessel elements; and the low ratio of length between imperforate tracheary elements and vessel elements. Pit membrane remnants are characteristically present to various degrees in perforations of vessel elements; this is considered a primitive feature that is related to other primitive vessel features. Specialized features of Hedyosmum wood include septate fiber-tracheids with much reduced borders on pits; vasicentric axial parenchyma; and absence of uniseriate rays (in wood …


A Complete Index To The Butler University Botanical Studies, A Journal Of Original Research Published By Butler University 1929-1964, Rebecca W. Dolan Jan 1992

A Complete Index To The Butler University Botanical Studies, A Journal Of Original Research Published By Butler University 1929-1964, Rebecca W. Dolan

Scholarship and Professional Work - LAS

For 35 years, the Botany Department of Butler University published a journal of research conducted by Butler faculty, students. and other Indiana botanists. Many of the papers contain valuable historical studies. especially floristic surveys that document Indiana's vegetation in past decades. This article presents a complete index for the journal. arranged both chronologically and alphabetically. Reprints of articles are still available.


List Of Museum Type Repositories, Stephen L. Wood, Donald E. Bright Jr. Jan 1992

List Of Museum Type Repositories, Stephen L. Wood, Donald E. Bright Jr.

Great Basin Naturalist Memoirs

No abstract provided.


Stubble : Friend And Foe, Department Of Agriculture And Food, Western Australia Jan 1992

Stubble : Friend And Foe, Department Of Agriculture And Food, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

Several articles in this issue of the Journal of Agriculture discuss some of the important issues of stubble management. The articles are condensed from some of the papers presented at a stubble workshop at Geraldton in 1991.


New Yellow Serradella Varieties For Low Rainfall Pastures, Clinton Revell Jan 1992

New Yellow Serradella Varieties For Low Rainfall Pastures, Clinton Revell

Journal of the Department of Agriculture, Western Australia, Series 4

Large areas of acidic, sandy soils in Western Australia's low and medium rainfall, wheatsheep areas are suited to the pasture legume, yellow serradella.

In the past, a lack of varieties with suitable maturity has limited the use of this species.

New varieties developed in Western Australia and significantly earlier in maturity than traditional types can now extend the use of yellow serradella into these regions.


Managing Brome Grass In The Wheat:Lupin Rotation, Aik Hock Cheam, Gurget Gil, Christine Zaicou Jan 1992

Managing Brome Grass In The Wheat:Lupin Rotation, Aik Hock Cheam, Gurget Gil, Christine Zaicou

Journal of the Department of Agriculture, Western Australia, Series 4

Some farmers and scientists are questioning the sustainability of the cereal:lupin rotation in the Western Australian wheatbelt.

Being a 'tight' rotation, its continuation is constantly under threat by disease, especially lupin root rots caused by Pleiochaeta (the brown spot organism) and Rhizoctonia fungi. To control disease, some farmers have lengthened the rotation to three years, such as wheat:wheat:lupins or wheat:barley:lupins. The longer cereal phase also helps to stabilise soil against wind erosion. However, such rotations can lead to a rapid buildup of brome grass during the two consecutive years of cereals. The implications of these rotations on the severity of …


Opportunity Knocks : Sowing Wheat Early In The North-Eastern Wheatbelt, Nicole Kerr, Doug Abrecht Jan 1992

Opportunity Knocks : Sowing Wheat Early In The North-Eastern Wheatbelt, Nicole Kerr, Doug Abrecht

Journal of the Department of Agriculture, Western Australia, Series 4

Farmers consider many factors in deciding whether to start sowing wheat, but the most important are the amount of rain and time of year. In this study we assessed the chances of farmers in the north-eastern wheatbelt (less than 325 mm rainfall) receiving enough rain to sow wheat early. In low rainfall areas such as this, where an early finish to the season is likely, it is especially important that farmers take advantage of all early sowing opportunities. The potential benefits of sowing wheat early generally outweigh the associated risks, particularly in lower rainfall areas. However, early sowing depends on …


The Impact Of Red Kangaroos On The Rangelands, Grant Norbury, Dale Norbury Jan 1992

The Impact Of Red Kangaroos On The Rangelands, Grant Norbury, Dale Norbury

Journal of the Department of Agriculture, Western Australia, Series 4

Kangaroos and other native animals should be maintained across their natural range, including areas set aside for pastoral use. But the added grazing pressure on native vegetation from sheep, cattle and feral animals, together with unnaturally high numbers of kangaroos, has seriously degraded much of our rangelands. Cattle and sheep numbers are relatively easy to control. The same cannot be said for kangaroos. Access to widespread man-made watering points has allowed kangaroos to continue breeding when normally a shortage of water would suppress reproduction.

Pastoralists complain that commercial kangaroo shooting is not always effective in preventing damage caused by kangaroos. …


Endemism In The Vascular Flora Of The Juan Fernandez Islands, Tod F. Stuessy, Clodomiro Marticorena, Roberto Rodriguez R., Daniel J. Crawford, Mario Silva O. Jan 1992

Endemism In The Vascular Flora Of The Juan Fernandez Islands, Tod F. Stuessy, Clodomiro Marticorena, Roberto Rodriguez R., Daniel J. Crawford, Mario Silva O.

Aliso: A Journal of Systematic and Floristic Botany

The Juan Fernandez archipelago contains 361 vascular plant species including 53 ferns, 65 monocots, and 243 dicots. Represented are 73 families and 219 genera. There is one endemic family (Lactoridaceae), 12 endemic genera, and 126 endemic species. The native vascular flora has II% endemism at the generic level and 60% at the specific level. Among the endemic species, 23 are ferns, 15 are monocots, and 88 are dicots. Of the endemic dicots, 29 species are Compositae, making up 33% of the endemic dicot flora. Most (97%) of the endemic angiosperms are perennials, and 64% of the dicots are woody (shrubs, …


Abnormal Cones In Cupressus Sempervirens, Simcha Lev-Yadun Jan 1992

Abnormal Cones In Cupressus Sempervirens, Simcha Lev-Yadun

Aliso: A Journal of Systematic and Floristic Botany

Abnormal cones found in Cupressus sempervirens include bisexual cones and double female and male cones. They are very infrequent, but there are individual trees with a tendency to produce such cones. We suggest that these cones reflect changes in normal hormonal balance.


Test Detects Resistant Green Peach Aphids In Lupins, Francoise Berlandier, Ian Dadour Jan 1992

Test Detects Resistant Green Peach Aphids In Lupins, Francoise Berlandier, Ian Dadour

Journal of the Department of Agriculture, Western Australia, Series 4

Confirmation of insecticide resistance in green peach aphid in Western Australia's lupin crops means farmers will have to choose insecticides much more carefully to control this pest. Resistance within an aphid population varies, and when resistant aphids are no longer exposed to insecticides, they may revert back to being susceptible in as little as one generation. Furthermore, when these revertant populations are exposed to the same insecticides in the future, resistance quickly reoccurs. In this article, the authors discuss a test to determine the extent of insecticide resistance in green peach aphid and how to manage it.


Cliff Lake Bench Research Natural Area: Problems Encountered In Monitoring Vegetation Change On Mountain Grasslands, Walter F. Mueggler Jan 1992

Cliff Lake Bench Research Natural Area: Problems Encountered In Monitoring Vegetation Change On Mountain Grasslands, Walter F. Mueggler

Aspen Bibliography

No abstract provided.


Armillaria Root Rot In The Canadian Prairie Provinces, K. I. Mallett Jan 1992

Armillaria Root Rot In The Canadian Prairie Provinces, K. I. Mallett

Aspen Bibliography

No abstract provided.