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• 2091. [Article] The agronomic, environmental, and economic implications of the introduction of terbacil for weed control in Oregon commercial peppermint operations

  The use of terbacil for weed control was adapted by a high percentage of Oregon peppermint growers soon after its introduction in 1967. To help clarify some of the implications of terbacil usage, three ...

  Citation × Citation Citation Abstract Copy Title: The agronomic, environmental, and economic implications of the introduction of terbacil for weed control in Oregon commercial peppermint operations Author: Harris, James O. The use of terbacil for weed control was adapted by a high percentage of Oregon peppermint growers soon after its introduction in 1967. To help clarify some of the implications of terbacil usage, three studies were undertaken to collect information concerning (a) the movement and build-up of terbacil in various soils, (b) possible contamination of "waste" and ground irrigation water, and (c) the economic and cultural practice changes which resulted from terbacil usage. Using soil samples taken from commercial fields, depth of terbacil penetration into the soil profile was greater in lighter soils than in heavier soils. Residues seemed to accumulate near the surface of the ridge in rill irrigated fields. No evidence of continued build-up of the chemical with repeated applications was seen in the soils tested. Analysis of water samples taken from the waste ditch of a rill irrigated field showed only a low concentration of terbacil, and this decreased with each irrigation. No residues were found in water samples taken from two shallow wells located in treated fields. Analysis of cash weed control costs of growers in the Willamette Valley and Jefferson County showed sizeable savings with the use of terbacil in the majority of cases. There was a corresponding savings in time spent on mint operations. This savings in time and money may have contributed to the increase in peppermint acreage noted among those growers who participated in the study. Because of fear of spreading Verticillium wilt (Verticillium albo-atrum or V. dahliae), many growers had quit annual plowing of their mint before terbacil was introduced, and many had experienced problems with weeds under this scheme. When terbacil was introduced, it appeared to solve this problem by giving very good weed control on most of the weeds. However, problems developed because most perennial weeds and a few annuals were not controlled. At present this is a major concern. Terbacil has a long residual life in the soil which can be an important advantage for control of weeds in peppermint since peppermint is a perennial crop and quite tolerant of terbacil. However, few other crops are tolerant. Over half of the growers interviewed who had taken a treated field out of production had experienced trouble in following with other crops. Unfortunately, there seems to be no pattern or set of circumstances which can help the grower predict whether or not he will have difficulty. Title: The agronomic, environmental, and economic implications of the introduction of terbacil for weed control in Oregon commercial peppermint operations Author: Harris, James O. The use of terbacil for weed control was adapted by a high percentage of Oregon peppermint growers soon after its introduction in 1967. To help clarify some of the implications of terbacil usage, three studies were undertaken to collect information concerning (a) the movement and build-up of terbacil in various soils, (b) possible contamination of "waste" and ground irrigation water, and (c) the economic and cultural practice changes which resulted from terbacil usage. Using soil samples taken from commercial fields, depth of terbacil penetration into the soil profile was greater in lighter soils than in heavier soils. Residues seemed to accumulate near the surface of the ridge in rill irrigated fields. No evidence of continued build-up of the chemical with repeated applications was seen in the soils tested. Analysis of water samples taken from the waste ditch of a rill irrigated field showed only a low concentration of terbacil, and this decreased with each irrigation. No residues were found in water samples taken from two shallow wells located in treated fields. Analysis of cash weed control costs of growers in the Willamette Valley and Jefferson County showed sizeable savings with the use of terbacil in the majority of cases. There was a corresponding savings in time spent on mint operations. This savings in time and money may have contributed to the increase in peppermint acreage noted among those growers who participated in the study. Because of fear of spreading Verticillium wilt (Verticillium albo-atrum or V. dahliae), many growers had quit annual plowing of their mint before terbacil was introduced, and many had experienced problems with weeds under this scheme. When terbacil was introduced, it appeared to solve this problem by giving very good weed control on most of the weeds. However, problems developed because most perennial weeds and a few annuals were not controlled. At present this is a major concern. Terbacil has a long residual life in the soil which can be an important advantage for control of weeds in peppermint since peppermint is a perennial crop and quite tolerant of terbacil. However, few other crops are tolerant. Over half of the growers interviewed who had taken a treated field out of production had experienced trouble in following with other crops. Unfortunately, there seems to be no pattern or set of circumstances which can help the grower predict whether or not he will have difficulty. Close

• 2092. [Article] Labops hesperius Uhler : biology and impact of Oregon rangelands (Hemiptera: Miridae)

  The seasonal development and habits of Labops hesperius Uhler were studied in rangeland seeded to intermediate wheatgrass (Agropyron intermediurn (Host) Beauv. ) in Baker County, Oregon, The first nymphs ...

  Citation × Citation Citation Abstract Copy Title: Labops hesperius Uhler : biology and impact of Oregon rangelands (Hemiptera: Miridae) Author: Todd, James Gordon The seasonal development and habits of Labops hesperius Uhler were studied in rangeland seeded to intermediate wheatgrass (Agropyron intermediurn (Host) Beauv. ) in Baker County, Oregon, The first nymphs appeared on March 22, and required about one week to complete each of the five nymphal stadia. Most small nymphs stayed on the ground beneath the straw and litter during daylight and fed on the leaf blades of grasses at night. Fifth instars and adults fed on the leaf blades during both the day and night. The adults began to emerge on April 26, and the preoviposition period of the females lasted about two weeks. A maximum of 48 eggs was found in the ovaries of a single female, but the mean number of eggs laid per female was estimated at twenty-one and nine eggs, respectively, at two study sites. Most eggs had been laid by June 15, and the eggs remained dormant until March of the following year. Thus L. hesperius completed its development and reproduction in about 2 1/2 months and had an obligatory diapause that lasted about 9 1/2 months. Labops hesperius was found in a variety of habitats, but the greatest numbers were found in two dense stands of intermediate wheatgrass which had received little or no grazing during the past 12 years. Other grasses used as food included Agropyron desertorum (Fisch. ) Schult., A. repens (L. ) Beauv., A. spicatum (Pursh) Scribn. and Smith, A. trichophorum (Link) Richt. , Bromus carinatus Hook and Arn., B. tectorum L., Dactylis glomerata L. , Festuca idahoensis Elmer. Hordeum vulgare L. , Koeleria cristata (L. ) Pers. , Poa bulbosa L. , P. pratensis L., Secale cereale L., and Stipa lemmonii (Vasey) Scribn. Females usually oviposited in dry straws of grass that had been produced during the previous season, because oviposition was completed before straws suitable for oviposition were produced. However, dry straws of bulbous bluegrass (Poa bulbosa L. ) were used for oviposition during the same season in which they grew, since bulbous bluegrass matured earlier than other grasses and had dried before oviposition was completed. Straws of bulbous bluegrass were the preferred oviposition site although bulbous bluegrass was rare in most ranges. Straws of Agropyron desertorum, A. intermedium, and A. spicatum were also readily used for oviposition. The effect of feeding injury by L. hesperius on the yield and composition of wheatgrass was determined by chemical analysis of forage samples from sprayed and unsprayed plots. Feeding injury reduced the yield and nutritional value of wheatgrass by removing the cell contents from the leaves. The loss of forage production was about 18 percent in May when feeding injury was most severe. However, the grass continued to grow because of adequate moisture and when the grass reached maturity near the end of July, the loss of forage production was only about two percent of the total forage production. Exploratory tests suggested that field burning, removal of a hay crop, and grazing might reduce densities of L. hesperius by destroying the overwintering eggs and the straw used for oviposition. Insecticidal control did not appear to be economical, since the return per acre from rangelands was small and since frequently the cost of treatment would have been greater than the value of the forage lost to L. hesperius. Title: Labops hesperius Uhler : biology and impact of Oregon rangelands (Hemiptera: Miridae) Author: Todd, James Gordon The seasonal development and habits of Labops hesperius Uhler were studied in rangeland seeded to intermediate wheatgrass (Agropyron intermediurn (Host) Beauv. ) in Baker County, Oregon, The first nymphs appeared on March 22, and required about one week to complete each of the five nymphal stadia. Most small nymphs stayed on the ground beneath the straw and litter during daylight and fed on the leaf blades of grasses at night. Fifth instars and adults fed on the leaf blades during both the day and night. The adults began to emerge on April 26, and the preoviposition period of the females lasted about two weeks. A maximum of 48 eggs was found in the ovaries of a single female, but the mean number of eggs laid per female was estimated at twenty-one and nine eggs, respectively, at two study sites. Most eggs had been laid by June 15, and the eggs remained dormant until March of the following year. Thus L. hesperius completed its development and reproduction in about 2 1/2 months and had an obligatory diapause that lasted about 9 1/2 months. Labops hesperius was found in a variety of habitats, but the greatest numbers were found in two dense stands of intermediate wheatgrass which had received little or no grazing during the past 12 years. Other grasses used as food included Agropyron desertorum (Fisch. ) Schult., A. repens (L. ) Beauv., A. spicatum (Pursh) Scribn. and Smith, A. trichophorum (Link) Richt. , Bromus carinatus Hook and Arn., B. tectorum L., Dactylis glomerata L. , Festuca idahoensis Elmer. Hordeum vulgare L. , Koeleria cristata (L. ) Pers. , Poa bulbosa L. , P. pratensis L., Secale cereale L., and Stipa lemmonii (Vasey) Scribn. Females usually oviposited in dry straws of grass that had been produced during the previous season, because oviposition was completed before straws suitable for oviposition were produced. However, dry straws of bulbous bluegrass (Poa bulbosa L. ) were used for oviposition during the same season in which they grew, since bulbous bluegrass matured earlier than other grasses and had dried before oviposition was completed. Straws of bulbous bluegrass were the preferred oviposition site although bulbous bluegrass was rare in most ranges. Straws of Agropyron desertorum, A. intermedium, and A. spicatum were also readily used for oviposition. The effect of feeding injury by L. hesperius on the yield and composition of wheatgrass was determined by chemical analysis of forage samples from sprayed and unsprayed plots. Feeding injury reduced the yield and nutritional value of wheatgrass by removing the cell contents from the leaves. The loss of forage production was about 18 percent in May when feeding injury was most severe. However, the grass continued to grow because of adequate moisture and when the grass reached maturity near the end of July, the loss of forage production was only about two percent of the total forage production. Exploratory tests suggested that field burning, removal of a hay crop, and grazing might reduce densities of L. hesperius by destroying the overwintering eggs and the straw used for oviposition. Insecticidal control did not appear to be economical, since the return per acre from rangelands was small and since frequently the cost of treatment would have been greater than the value of the forage lost to L. hesperius. Close

• 2093. [Article] Paleozoic stratigraphy of the southern Mahogany Hills, Eureka County, Nevada

  Paleozoic dolomites, limestones, and detrital clastic rocks were mapped in the Bellevue Peak 15 minute quadrangle in the southern Mahogany Hills, Nevada. Sedimentary rock units in this area represent shallow-shelf ...

  Citation × Citation Citation Abstract Copy Title: Paleozoic stratigraphy of the southern Mahogany Hills, Eureka County, Nevada Author: Schalla, Robert Allen Paleozoic dolomites, limestones, and detrital clastic rocks were mapped in the Bellevue Peak 15 minute quadrangle in the southern Mahogany Hills, Nevada. Sedimentary rock units in this area represent shallow-shelf eastern assemblage deposits. Shallow-shelf carbonates characterized deposition from at least Ordovician through Late Devonian time, when clastics derived from the Antler orogenic belt overwhelmed the previous environments. The Ordovician Eureka Quartzite, a quartz arenite of unknown thickness in the map area, probably represents a beach-bar-dune environment. The superjacent Hanson Creek Formation comprises limestones and dolomites of probable Late Ordovician-Early Silurian age and represents a semi-restricted lagoonal environment. Total thickness of this unit in the map area is unknown. Above the interval black dolomites which was chosen as the top of the Hanson Creek, are light-colored dolomites which are assigned to the Lone Mountain Dolomite. These deposits are generally coarse-grained, recrystallized, and lack primary structures. An abrupt contact, interpreted as an unconformity, marks the top of this formation. Extremely fine-grained, largely unfossiliferous, light grey dolomites of the Beacon Peak Dolomite (107 m thick) overlie the Lone Mountain Dolomite in the eastern part of the map area. To the west, bioclastic limestones and dolomites of the Mc Colley Canyon Formation (155 m thick) overlie the Lone Mountain Dolomite. The Beacon Peak Dolomite and the Mc Colley Canyon Formation are thought to be lateral equivalents in this area, with the Beacon Peak having been deposited in a supratidal environment and the Mc Colley Canyon in a subtidal, normal-marine environment. Progressive deepening resulted in an eastward shift of these facies during the late Early Devonian. Evidence of shoaling is present in the crinoidal dolomites of the Sadler Ranch Formation (137 m thick). This shoaling continued and resulted in the westward incursion of a tongue of the upper Oxyoke Canyon Sandstone (21 m thick) during the early Middle Devonian. Deepening of the carbonate shelf is again evident in the eastward retreat of the high-energy Oxyoke Canyon Sandstone environment and the initiation of shallow-water, Middle Devonian Simonson Dolomite (396 m thick) deposition in the map area. The superjacent Devils Gate Limestone represents increased water depth and enhanced circulation over the depositional platform. This shallow water carbonate environment persisted until detrital clastics from the Antler orogenic belt, to the west, terminated carbonate deposition in the map area. The presence of basinal deposits of the Roberts Mountains Formation and the Denay Limestone, 10 kilometers northwest of the map area at Lone Mountain, indicates that the shelf-slope break probably persisted west of the map area from at least the Late Silurian through the Middle Devonian. The stratigraphic sequence in the map area is typical for the area near Eureka, Nevada. Title: Paleozoic stratigraphy of the southern Mahogany Hills, Eureka County, Nevada Author: Schalla, Robert Allen Paleozoic dolomites, limestones, and detrital clastic rocks were mapped in the Bellevue Peak 15 minute quadrangle in the southern Mahogany Hills, Nevada. Sedimentary rock units in this area represent shallow-shelf eastern assemblage deposits. Shallow-shelf carbonates characterized deposition from at least Ordovician through Late Devonian time, when clastics derived from the Antler orogenic belt overwhelmed the previous environments. The Ordovician Eureka Quartzite, a quartz arenite of unknown thickness in the map area, probably represents a beach-bar-dune environment. The superjacent Hanson Creek Formation comprises limestones and dolomites of probable Late Ordovician-Early Silurian age and represents a semi-restricted lagoonal environment. Total thickness of this unit in the map area is unknown. Above the interval black dolomites which was chosen as the top of the Hanson Creek, are light-colored dolomites which are assigned to the Lone Mountain Dolomite. These deposits are generally coarse-grained, recrystallized, and lack primary structures. An abrupt contact, interpreted as an unconformity, marks the top of this formation. Extremely fine-grained, largely unfossiliferous, light grey dolomites of the Beacon Peak Dolomite (107 m thick) overlie the Lone Mountain Dolomite in the eastern part of the map area. To the west, bioclastic limestones and dolomites of the Mc Colley Canyon Formation (155 m thick) overlie the Lone Mountain Dolomite. The Beacon Peak Dolomite and the Mc Colley Canyon Formation are thought to be lateral equivalents in this area, with the Beacon Peak having been deposited in a supratidal environment and the Mc Colley Canyon in a subtidal, normal-marine environment. Progressive deepening resulted in an eastward shift of these facies during the late Early Devonian. Evidence of shoaling is present in the crinoidal dolomites of the Sadler Ranch Formation (137 m thick). This shoaling continued and resulted in the westward incursion of a tongue of the upper Oxyoke Canyon Sandstone (21 m thick) during the early Middle Devonian. Deepening of the carbonate shelf is again evident in the eastward retreat of the high-energy Oxyoke Canyon Sandstone environment and the initiation of shallow-water, Middle Devonian Simonson Dolomite (396 m thick) deposition in the map area. The superjacent Devils Gate Limestone represents increased water depth and enhanced circulation over the depositional platform. This shallow water carbonate environment persisted until detrital clastics from the Antler orogenic belt, to the west, terminated carbonate deposition in the map area. The presence of basinal deposits of the Roberts Mountains Formation and the Denay Limestone, 10 kilometers northwest of the map area at Lone Mountain, indicates that the shelf-slope break probably persisted west of the map area from at least the Late Silurian through the Middle Devonian. The stratigraphic sequence in the map area is typical for the area near Eureka, Nevada. Close

• 2094. [Article] An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability

  Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel ...

  Citation × Citation Citation Abstract Copy Title: An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability Author: Morét, Stephanie L. Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel and if the channel stability survey that was being used accurately predicted the channels resistance to change resulting from a flood. The channel stability survey that was used was the method described in the 'Channel Stability Evaluation and Stream Reach Inventory' designed by the USDA Forest Service, Northern Region, in Colorado (Pfankuch, 1978). This was a non-parametric study, based on an opportunity to reoccupy survey locations from a previous study. A model was proposed to describe the 1995 ratings as predictions for change should a flood event occur. This predicted change was compared to the actual change that occurred as a result of the 1996 flood in order to test the surveys ability to accurately predict change. Changes in the survey totals, the 15 channel stability indicator items that compose the survey, and the sediment distribution were evaluated within and between years at the reach, station and stream scale. An increase in the percentage of fine gravel occurred at all scales when post-flood and pre-flood sediment distribution was compared. Except for an increase in fine gravel, the stream remained similar to its pre-flood state. In 1995, the stream's channel stability was rated as 'fair', indicating that a moderate amount of change should take place if a flood occurred. The 1995 predictions for change did not match the actual change observed after the February 1996 flood at the three scales when defined by the survey totals. When independently evaluating the fifteen individual channel stability indicator items, a considerable amount of change was detected at the reach level. Although change occurred in the indicator items at each reach, the stream average for each of the independent indicator items was similar between the two years. This may indicate that, although change occurred at the reach level, the stream maintained its physical diversity after the flood. The survey method was unable to accurately predict changes to Oak Creek incurred by the February 1996 flood when viewed at the entire stream level, yet it may be more applicable at the reach level when viewing specific changes to channel stability indicator items. In general, the Stream Reach Inventory and Channel Stability Evaluation is designed for observational efficiency but does not have sufficient scientific basis or measurement precision to accurately predict the extent or type of channel change. Title: An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability Author: Morét, Stephanie L. Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel and if the channel stability survey that was being used accurately predicted the channels resistance to change resulting from a flood. The channel stability survey that was used was the method described in the 'Channel Stability Evaluation and Stream Reach Inventory' designed by the USDA Forest Service, Northern Region, in Colorado (Pfankuch, 1978). This was a non-parametric study, based on an opportunity to reoccupy survey locations from a previous study. A model was proposed to describe the 1995 ratings as predictions for change should a flood event occur. This predicted change was compared to the actual change that occurred as a result of the 1996 flood in order to test the surveys ability to accurately predict change. Changes in the survey totals, the 15 channel stability indicator items that compose the survey, and the sediment distribution were evaluated within and between years at the reach, station and stream scale. An increase in the percentage of fine gravel occurred at all scales when post-flood and pre-flood sediment distribution was compared. Except for an increase in fine gravel, the stream remained similar to its pre-flood state. In 1995, the stream's channel stability was rated as 'fair', indicating that a moderate amount of change should take place if a flood occurred. The 1995 predictions for change did not match the actual change observed after the February 1996 flood at the three scales when defined by the survey totals. When independently evaluating the fifteen individual channel stability indicator items, a considerable amount of change was detected at the reach level. Although change occurred in the indicator items at each reach, the stream average for each of the independent indicator items was similar between the two years. This may indicate that, although change occurred at the reach level, the stream maintained its physical diversity after the flood. The survey method was unable to accurately predict changes to Oak Creek incurred by the February 1996 flood when viewed at the entire stream level, yet it may be more applicable at the reach level when viewing specific changes to channel stability indicator items. In general, the Stream Reach Inventory and Channel Stability Evaluation is designed for observational efficiency but does not have sufficient scientific basis or measurement precision to accurately predict the extent or type of channel change. Close

• 2095. [Article] An evaluation of Oregon Youth Conservation Corps 1996 summer programs

  The Oregon Youth Conservation Corps (OYCC) is a youth work program created by the Oregon Legislature in 1987. The OYCC provides both summer and year-round employment programs primarily for disadvantaged ...

  Citation × Citation Citation Abstract Copy Title: An evaluation of Oregon Youth Conservation Corps 1996 summer programs Author: Miller, Marc S. The Oregon Youth Conservation Corps (OYCC) is a youth work program created by the Oregon Legislature in 1987. The OYCC provides both summer and year-round employment programs primarily for disadvantaged and at-risk youth. The legislatively defined purpose of the OYCC is to protect, conserve, and improve the natural, historical, and cultural resources of the state, and to increase the education, training, and employment opportunities for participating youth. In addition, youth are given the opportunity to improve work skills and work-related social skills, develop the work ethic, and increase employability. The OYCC's impact on Oregon's resources, such as the improvements made to parks and the enhancement of public recreation areas, has been well documented. What has not been methodically studied are the outcomes of OYCC participation on youths' work skills, social skills, employability, and educational goals. This study examined participant outcomes for 400 of the over 600 youth enrolled in OYCC 1996 summer programs. Summer programs operate in nearly all of Oregon's 36 counties, and programs vary in length from 5 weeks to 10 weeks duration. Crew sizes vary from 4 to 10 participants, and are led by an adult crew leader. Pretest surveys were completed by participants and crew leaders at the beginning of each program. Participants and crew leaders completed posttest surveys again at the end of each program. Retrospective (post-then pre) pretests were also used. Measures were adopted from a Colorado State University evaluation of Youth Conservation Corps (Johnson, Driver, Ross, & Shikiar, 1982) These measures assessed changes in work skills, work-related social skills, educational goals, and potential for future employability. Data were analyzed to determine if outcomes of OYCC participation varied by program length, residential status, or participants' risk status. Investigator-designed measures were used to obtain demographic data. Both the traditional pretest-post test and the retrospective pretest methodologies revealed significant increases in participants' work competence and skills, work attitudes and behaviors, and comfort with diversity among co-workers. Increases were most significant among higher risk youth. Residential programs were particularly effective. Suggestions for future evaluation development and implementation are made. Title: An evaluation of Oregon Youth Conservation Corps 1996 summer programs Author: Miller, Marc S. The Oregon Youth Conservation Corps (OYCC) is a youth work program created by the Oregon Legislature in 1987. The OYCC provides both summer and year-round employment programs primarily for disadvantaged and at-risk youth. The legislatively defined purpose of the OYCC is to protect, conserve, and improve the natural, historical, and cultural resources of the state, and to increase the education, training, and employment opportunities for participating youth. In addition, youth are given the opportunity to improve work skills and work-related social skills, develop the work ethic, and increase employability. The OYCC's impact on Oregon's resources, such as the improvements made to parks and the enhancement of public recreation areas, has been well documented. What has not been methodically studied are the outcomes of OYCC participation on youths' work skills, social skills, employability, and educational goals. This study examined participant outcomes for 400 of the over 600 youth enrolled in OYCC 1996 summer programs. Summer programs operate in nearly all of Oregon's 36 counties, and programs vary in length from 5 weeks to 10 weeks duration. Crew sizes vary from 4 to 10 participants, and are led by an adult crew leader. Pretest surveys were completed by participants and crew leaders at the beginning of each program. Participants and crew leaders completed posttest surveys again at the end of each program. Retrospective (post-then pre) pretests were also used. Measures were adopted from a Colorado State University evaluation of Youth Conservation Corps (Johnson, Driver, Ross, & Shikiar, 1982) These measures assessed changes in work skills, work-related social skills, educational goals, and potential for future employability. Data were analyzed to determine if outcomes of OYCC participation varied by program length, residential status, or participants' risk status. Investigator-designed measures were used to obtain demographic data. Both the traditional pretest-post test and the retrospective pretest methodologies revealed significant increases in participants' work competence and skills, work attitudes and behaviors, and comfort with diversity among co-workers. Increases were most significant among higher risk youth. Residential programs were particularly effective. Suggestions for future evaluation development and implementation are made. Close

• 2096. [Article] Elderly women and activewear : their preferences and fitting problems

  The purpose of this study was to determine whether women aged 65 and older are wearing sweatshirts and sweatpants for activewear, and, if so, to investigate the types of activities they are worn for, reasons ...

  Citation × Citation Citation Abstract Copy Title: Elderly women and activewear : their preferences and fitting problems Author: Berman, Laura G. The purpose of this study was to determine whether women aged 65 and older are wearing sweatshirts and sweatpants for activewear, and, if so, to investigate the types of activities they are worn for, reasons for wearing, feature preferences, and fitting problems. While sweatshirts and sweatpants have been popularly worn by younger generations, there is little published research on their wear by the elderly. A convenience sample of 222 female members aged 65 and older taken from 34 Family and Community Education (FCE) extension study groups within four counties in the Willamette Valley of western Oregon was used in the research. A questionnaire-survey was administered at FCE meetings to provide quantitative and qualitative data. Eighty-three percent or 185 participants affirmatively answered to wearing either sweatshirts, sweatpants, or both garments of sweats attire. The largest percentage of respondents (43%) reported they "Usually wear sweatshirts and sometimes wear sweatpants". Activities with the highest frequency cited by respondents for wearing sweats attire included (in descending order): (a) exercise, (b) home-based indoor activities and situations, and (c) outdoor activities and situations. During the winter, 79% of the participants wore sweats attire frequently (a minimum of 2-3 times per week). Extremely important reasons cited for wearing sweats attire were "Warmth" and "Easy to care for or launder". The most highly desired features in sweats attire included: pullover sweatshirts with raglan sleeves, sweatpants with an elastic waistband and pockets, medium thick/medium weight, cotton/manufactured fiber blends, fleece interior, and muted colors that hide soil. Clothing size was more frequently related to these preferences than health status or age. Excess lengths of sleeves and pant legs, and tight, high necklines were the most frequent fitting problems cited. ANOVA and Newman-Keuls Multiple Comparison Procedure were used to analyze relationships. Poor health status and increased fitting problems showed a statistically significant relationship at p≤.01. Sweats attire provoked either very positive or very negative written comments. Non-wearing participants reacted negatively to the appearance and warmth of sweats attire, whereas, wearing-participants reacted strongly to benefits of comfort and warmth. Practical for lifestyle and easy manageability when dressing and undressing were also high considerations for positive respondents. Additional uses cited by respondents for sweats attire included sleepwear. The findings imply that sweats attire is frequently worn by active, older Oregon women for casual, familiar activities, situations, and environments. Also implied is the need for manufacturers and retailers to recognize the diversity of this heterogeneous population. Stereotypical images and clothing styles can be challenged to address the elderly population's needs for clothing comfort and current style, while offering functionality with such special features as extra pockets; shorter lengths with adequate torso ease; wider, lower necklines for postural changes; light weight fabrics with warmth; and easy-care finishes. Title: Elderly women and activewear : their preferences and fitting problems Author: Berman, Laura G. The purpose of this study was to determine whether women aged 65 and older are wearing sweatshirts and sweatpants for activewear, and, if so, to investigate the types of activities they are worn for, reasons for wearing, feature preferences, and fitting problems. While sweatshirts and sweatpants have been popularly worn by younger generations, there is little published research on their wear by the elderly. A convenience sample of 222 female members aged 65 and older taken from 34 Family and Community Education (FCE) extension study groups within four counties in the Willamette Valley of western Oregon was used in the research. A questionnaire-survey was administered at FCE meetings to provide quantitative and qualitative data. Eighty-three percent or 185 participants affirmatively answered to wearing either sweatshirts, sweatpants, or both garments of sweats attire. The largest percentage of respondents (43%) reported they "Usually wear sweatshirts and sometimes wear sweatpants". Activities with the highest frequency cited by respondents for wearing sweats attire included (in descending order): (a) exercise, (b) home-based indoor activities and situations, and (c) outdoor activities and situations. During the winter, 79% of the participants wore sweats attire frequently (a minimum of 2-3 times per week). Extremely important reasons cited for wearing sweats attire were "Warmth" and "Easy to care for or launder". The most highly desired features in sweats attire included: pullover sweatshirts with raglan sleeves, sweatpants with an elastic waistband and pockets, medium thick/medium weight, cotton/manufactured fiber blends, fleece interior, and muted colors that hide soil. Clothing size was more frequently related to these preferences than health status or age. Excess lengths of sleeves and pant legs, and tight, high necklines were the most frequent fitting problems cited. ANOVA and Newman-Keuls Multiple Comparison Procedure were used to analyze relationships. Poor health status and increased fitting problems showed a statistically significant relationship at p≤.01. Sweats attire provoked either very positive or very negative written comments. Non-wearing participants reacted negatively to the appearance and warmth of sweats attire, whereas, wearing-participants reacted strongly to benefits of comfort and warmth. Practical for lifestyle and easy manageability when dressing and undressing were also high considerations for positive respondents. Additional uses cited by respondents for sweats attire included sleepwear. The findings imply that sweats attire is frequently worn by active, older Oregon women for casual, familiar activities, situations, and environments. Also implied is the need for manufacturers and retailers to recognize the diversity of this heterogeneous population. Stereotypical images and clothing styles can be challenged to address the elderly population's needs for clothing comfort and current style, while offering functionality with such special features as extra pockets; shorter lengths with adequate torso ease; wider, lower necklines for postural changes; light weight fabrics with warmth; and easy-care finishes. Close

• 2097. [Article] A survey of alfalfa pollinators and polination in the San Joaquin Valley of California with emphasis on establishment of the alkali bee

  The study involves the establishment, management, and behavioral observations of Nomia melanderi Cockerell and Megachile rotundata (Fabricius) in California, a survey of native bees within western Fresno County, ...

  Citation × Citation Citation Abstract Copy Title: A survey of alfalfa pollinators and polination in the San Joaquin Valley of California with emphasis on establishment of the alkali bee Author: Torchio, Philip F. The study involves the establishment, management, and behavioral observations of Nomia melanderi Cockerell and Megachile rotundata (Fabricius) in California, a survey of native bees within western Fresno County, a determination of selfing and/or parthenocarpy in two fields of alfalfa, and observations on the honeybee as an alfalfa pollinator. The alkali bee is characterized. It is an endemic species limited to western North America. Eight artificial alkali bee nesting sites were constructed during the establishment program. Details of materials used during construction and their importance are discussed. Alkali bee cores used for introduction into California were procured in eastern Oregon and western Idaho, trucked to California, and planted in artificial sites. The heavy usage of insecticides in the area of study proved to be the greatest problem in the survival of the alkali bee. Observed toxicities of Dimethoate, Sevin, Malathion, Systex-Toxaphene, Toxaphene, DDT, Phosdrin, Dibrom, TEPP, Dylox, and Kelthane on the alkali bee were compared. The occurrence of multiple generations of the alkali bee in California is reported. Explanation of this behavior is based upon high soil temperatures (82° F. and above) during the nesting season. The importance of multiple generations is discussed. Biologies and importance of alkali bee parasites in California are described. Procedures for the control of some species are outlined. Methods of constructing trap nests for Megachile rotundata and their distribution throughout the San Joaquin Valley are described. Collections of these trap nests were then made and placed in one field so that readings on frequency of tripping, number of pollen loads required to provision cells, and time required to collect leafcuttings could be made. Observations on mating positions were described. The smallest males and largest females were reproductively isolated because of size difference. Parasites (Melittobia chalybii Ashmead and Monodontomeris montivagus Ashmead) and competitors (Ashmediella aridula Cockerell and Hylaeus grossicornis (Swenk and Cockerell) of Megachile rotundata are discussed. Melittobia chalybii Ashmead, a chalcid wasp, is potentially the most serious parasite and could decide the success or failure of M. rotundata in California. A survey of native bees was made in the area of study. Eight native species were found and their biologies described. Preferred pollen host plants were determined. Reasons why native bee biologies should be studied and understood are given. Two cages, one placed in a Tan Verde seed field and the second in a Ranger field, were used to calculate amount of seed produced from pathways other than by cross-pollination. Comparison of seed harvested from caged plots and field plots indicated that seed produced by non cross-pollination mechanisms could account for the average seed yields in California during recent years. Germination tests indicated, however, that seed produced by mechanisms other than cross-pollination is inferior. Only seven honey bees were observed collecting alfalfa pollen throughout the period of study. Consequently, no valid comparison between its pollinating capacity and that of wild bees could be made. Title: A survey of alfalfa pollinators and polination in the San Joaquin Valley of California with emphasis on establishment of the alkali bee Author: Torchio, Philip F. The study involves the establishment, management, and behavioral observations of Nomia melanderi Cockerell and Megachile rotundata (Fabricius) in California, a survey of native bees within western Fresno County, a determination of selfing and/or parthenocarpy in two fields of alfalfa, and observations on the honeybee as an alfalfa pollinator. The alkali bee is characterized. It is an endemic species limited to western North America. Eight artificial alkali bee nesting sites were constructed during the establishment program. Details of materials used during construction and their importance are discussed. Alkali bee cores used for introduction into California were procured in eastern Oregon and western Idaho, trucked to California, and planted in artificial sites. The heavy usage of insecticides in the area of study proved to be the greatest problem in the survival of the alkali bee. Observed toxicities of Dimethoate, Sevin, Malathion, Systex-Toxaphene, Toxaphene, DDT, Phosdrin, Dibrom, TEPP, Dylox, and Kelthane on the alkali bee were compared. The occurrence of multiple generations of the alkali bee in California is reported. Explanation of this behavior is based upon high soil temperatures (82° F. and above) during the nesting season. The importance of multiple generations is discussed. Biologies and importance of alkali bee parasites in California are described. Procedures for the control of some species are outlined. Methods of constructing trap nests for Megachile rotundata and their distribution throughout the San Joaquin Valley are described. Collections of these trap nests were then made and placed in one field so that readings on frequency of tripping, number of pollen loads required to provision cells, and time required to collect leafcuttings could be made. Observations on mating positions were described. The smallest males and largest females were reproductively isolated because of size difference. Parasites (Melittobia chalybii Ashmead and Monodontomeris montivagus Ashmead) and competitors (Ashmediella aridula Cockerell and Hylaeus grossicornis (Swenk and Cockerell) of Megachile rotundata are discussed. Melittobia chalybii Ashmead, a chalcid wasp, is potentially the most serious parasite and could decide the success or failure of M. rotundata in California. A survey of native bees was made in the area of study. Eight native species were found and their biologies described. Preferred pollen host plants were determined. Reasons why native bee biologies should be studied and understood are given. Two cages, one placed in a Tan Verde seed field and the second in a Ranger field, were used to calculate amount of seed produced from pathways other than by cross-pollination. Comparison of seed harvested from caged plots and field plots indicated that seed produced by non cross-pollination mechanisms could account for the average seed yields in California during recent years. Germination tests indicated, however, that seed produced by mechanisms other than cross-pollination is inferior. Only seven honey bees were observed collecting alfalfa pollen throughout the period of study. Consequently, no valid comparison between its pollinating capacity and that of wild bees could be made. Close

• 2098. [Article] Evaluating the financial risk involved in farmland investment decisions

  Investing in farmland is one of the most important decisions that farmers face in their lifetimes. Usually, large amounts of debt are required to purchase a substantial tract of land, thereby reducing ...

  Citation × Citation Citation Abstract Copy Title: Evaluating the financial risk involved in farmland investment decisions Author: Knox, Kenneth W. Investing in farmland is one of the most important decisions that farmers face in their lifetimes. Usually, large amounts of debt are required to purchase a substantial tract of land, thereby reducing the farmer's liquidity position and future borrowing capacity. Fixed debt commitments must be met by highly variable future farm income. Variable cash flows are the most critical in the first three to five years after the land purchase. After that time, the financial position has improved as a result of the principal payments and possible appreciation in the value of new and existing land holdings. An incorrect decision in purchasing land may result in prolonged cash flow problems and force partial liquidation or possibly bankruptcy. Oregon farmers want to know how much can be paid for land considering their objectives relating to the return they desire on their investment and the risk they are willing to accept that debt can be serviced after the proposed farm expansion. Two models were developed in this study. The first is a net present value model to determine the effect of critical variables on the maximum economically feasible price that can be paid for farmland. The second model developed for this study is a risk analysis model to evaluate the decision maker's ability to meet fixed debt payments and other cash commitments given probability distributions for prices and yields The net present value of an acre of land is determined by summing the discounted cash flows after taxes over the planning horizon for the tract to be purchased. Whole firm analysis, or direct comparison between present and proposed expanded operation, is used to determine the exact effects of tax consequences associated with the land purchase. The discount factor used is the desired after-tax rate of return on equity capital. The model considers the case where the planning horizon is shorter in years than the loan repayment period. The risk model determines gross farm income, which consists of product prices and yields, stochastically using triangular probability distributions. Operating expenses, amortization payments for term debt, net capital purchases associated with depreciable items, living expenses and withdrawals, and all taxes are subtracted from gross receipts to determine yearly cash flow. Items given in the output include the low cash balance at the end of the number of years for which the program was run, the probability of a negative cash balance occurring, and the probability of financial failure. The models were applied to two case farm studies in Sherman and Marion Counties. Empirical results of these case studies indicate that given current production costs and gross farm receipts, farmland must continue to appreciate at an annual compound rate of 9 percent for the duration of the planning horizon to justify current land prices. Other variables having a sizable impact on the net present value include gross receipts and operating expenses for the newly purchased tract, the purchase price, and the discount factor Decision makers who own their farm operations and have low previous debt commitments are the most capable of generating adequate cash flows. Farmers who have large amounts of debt outstanding and who lease portions of their operation may have problems generating a positive cash balance within four years after the purchase What farmers pay for land is influenced by the amount of risk that they are willing to take. Title: Evaluating the financial risk involved in farmland investment decisions Author: Knox, Kenneth W. Investing in farmland is one of the most important decisions that farmers face in their lifetimes. Usually, large amounts of debt are required to purchase a substantial tract of land, thereby reducing the farmer's liquidity position and future borrowing capacity. Fixed debt commitments must be met by highly variable future farm income. Variable cash flows are the most critical in the first three to five years after the land purchase. After that time, the financial position has improved as a result of the principal payments and possible appreciation in the value of new and existing land holdings. An incorrect decision in purchasing land may result in prolonged cash flow problems and force partial liquidation or possibly bankruptcy. Oregon farmers want to know how much can be paid for land considering their objectives relating to the return they desire on their investment and the risk they are willing to accept that debt can be serviced after the proposed farm expansion. Two models were developed in this study. The first is a net present value model to determine the effect of critical variables on the maximum economically feasible price that can be paid for farmland. The second model developed for this study is a risk analysis model to evaluate the decision maker's ability to meet fixed debt payments and other cash commitments given probability distributions for prices and yields The net present value of an acre of land is determined by summing the discounted cash flows after taxes over the planning horizon for the tract to be purchased. Whole firm analysis, or direct comparison between present and proposed expanded operation, is used to determine the exact effects of tax consequences associated with the land purchase. The discount factor used is the desired after-tax rate of return on equity capital. The model considers the case where the planning horizon is shorter in years than the loan repayment period. The risk model determines gross farm income, which consists of product prices and yields, stochastically using triangular probability distributions. Operating expenses, amortization payments for term debt, net capital purchases associated with depreciable items, living expenses and withdrawals, and all taxes are subtracted from gross receipts to determine yearly cash flow. Items given in the output include the low cash balance at the end of the number of years for which the program was run, the probability of a negative cash balance occurring, and the probability of financial failure. The models were applied to two case farm studies in Sherman and Marion Counties. Empirical results of these case studies indicate that given current production costs and gross farm receipts, farmland must continue to appreciate at an annual compound rate of 9 percent for the duration of the planning horizon to justify current land prices. Other variables having a sizable impact on the net present value include gross receipts and operating expenses for the newly purchased tract, the purchase price, and the discount factor Decision makers who own their farm operations and have low previous debt commitments are the most capable of generating adequate cash flows. Farmers who have large amounts of debt outstanding and who lease portions of their operation may have problems generating a positive cash balance within four years after the purchase What farmers pay for land is influenced by the amount of risk that they are willing to take. Close

• 2099. [Article] The Warner Valley Stock Company ; a geographic study

  This thesis is a case study of the Warner Valley Stock Company, a large eastern Oregon Stock Ranch, which utilizes over 680,000 acres of government grazing land. The purpose is to examine the background ...

  Citation × Citation Citation Abstract Copy Title: The Warner Valley Stock Company ; a geographic study Author: Hunt, Jack Horace This thesis is a case study of the Warner Valley Stock Company, a large eastern Oregon Stock Ranch, which utilizes over 680,000 acres of government grazing land. The purpose is to examine the background growth, and forces affecting the ranch. The relationship of man to land can be understood by presenting an organized view of the resources available and how he has utilized them. The ranch is located in South Warner Valley, 35 miles east of Lakeview, Oregon. The valley, a graben 4400 to 4500 feet above sea level, is surrounded by a higher, rolling plateau with elevations ranging from 5000 to 7000 feet. The high desert rangeland has a sparse sagebrush-bunch grass vegetation. Warner Valley is an interior drainage basin which accumulates water for irrigation on valley fields. The natural vegetation of the valley floor consists of tules, willows, and native grasses which supply hay. Early settlers arrived in the late 1860's and by the late 1870's a a number of people settled and an estimated 7000 to 8000 head of cattle were present, grazing on the range in the summer and wintering in the valley. The present ranch lands are owned largely as a result of land granted by Oregon through Swamp Land Laws. A controversy raged between homesteading settlers and the company for years, but was finally settled in favor of the company. Immediately after buying the company in 1936, William Kittridge began reclamation by constructing dikes and canals to control the water. Cultivating and irrigating fields to grow grain was also initiated. This reclamation program continues, with the most highly developed land now producing four tons of alfalfa annually per acre. Grazing rights on over 680,000 acres of government grazing lands are leased by the Company and support cattle five to seven months of the year while hay and grain crops are grown on the ranch. Grazing is controlled by the BLM through issuance of permits. Increasing competition by man for other uses of the rangeland such as wildlife refuges and recreation are a source of concern for the rancher. BLM is developing the range with multiple use concept in mind to achieve the maximum use possible. More intensive management of the range is increasing the rangecost to the rancher. This is a large concern with annual operating expenses of over one million dollars, a cattle inventory of approximately 15,000 head (including calves) and a feed mill-feed lot installation which assists in raising the animals from calves to finished market animals. The principle market is California, with transportation being a costly factor. The ranch as it now exists is the result of many forces. The physical elements place restrictions on the land, the most important being aridity, which does not allow diversification of agricultural production. At present cattle grazing is the most efficient land use. The large meat eating public assures a continued demand, although market requirements may deviate. Title: The Warner Valley Stock Company ; a geographic study Author: Hunt, Jack Horace This thesis is a case study of the Warner Valley Stock Company, a large eastern Oregon Stock Ranch, which utilizes over 680,000 acres of government grazing land. The purpose is to examine the background growth, and forces affecting the ranch. The relationship of man to land can be understood by presenting an organized view of the resources available and how he has utilized them. The ranch is located in South Warner Valley, 35 miles east of Lakeview, Oregon. The valley, a graben 4400 to 4500 feet above sea level, is surrounded by a higher, rolling plateau with elevations ranging from 5000 to 7000 feet. The high desert rangeland has a sparse sagebrush-bunch grass vegetation. Warner Valley is an interior drainage basin which accumulates water for irrigation on valley fields. The natural vegetation of the valley floor consists of tules, willows, and native grasses which supply hay. Early settlers arrived in the late 1860's and by the late 1870's a a number of people settled and an estimated 7000 to 8000 head of cattle were present, grazing on the range in the summer and wintering in the valley. The present ranch lands are owned largely as a result of land granted by Oregon through Swamp Land Laws. A controversy raged between homesteading settlers and the company for years, but was finally settled in favor of the company. Immediately after buying the company in 1936, William Kittridge began reclamation by constructing dikes and canals to control the water. Cultivating and irrigating fields to grow grain was also initiated. This reclamation program continues, with the most highly developed land now producing four tons of alfalfa annually per acre. Grazing rights on over 680,000 acres of government grazing lands are leased by the Company and support cattle five to seven months of the year while hay and grain crops are grown on the ranch. Grazing is controlled by the BLM through issuance of permits. Increasing competition by man for other uses of the rangeland such as wildlife refuges and recreation are a source of concern for the rancher. BLM is developing the range with multiple use concept in mind to achieve the maximum use possible. More intensive management of the range is increasing the rangecost to the rancher. This is a large concern with annual operating expenses of over one million dollars, a cattle inventory of approximately 15,000 head (including calves) and a feed mill-feed lot installation which assists in raising the animals from calves to finished market animals. The principle market is California, with transportation being a costly factor. The ranch as it now exists is the result of many forces. The physical elements place restrictions on the land, the most important being aridity, which does not allow diversification of agricultural production. At present cattle grazing is the most efficient land use. The large meat eating public assures a continued demand, although market requirements may deviate. Close

• 2100. [Article] Effects of residual and applied nitrogen on Nugaines wheat

  A study was made to evaluate the effect of different rates of N fertilization on Nugaines wheat. The variable N treatments provided different N regimes as a basis for evaluating potential diagnostic tests ...

  Citation × Citation Citation Abstract Copy Title: Effects of residual and applied nitrogen on Nugaines wheat Author: Laopirojana, Pojanee A study was made to evaluate the effect of different rates of N fertilization on Nugaines wheat. The variable N treatments provided different N regimes as a basis for evaluating potential diagnostic tests for assessing the N status of the wheat plant. The crop was grown in Lane county during the 1968 growing season on soil of the Malabon. series. To evaluate the treatment effects the yield of grain and dry matter, number of culms per foot of drill-row, leaf percentage, grain protein, test weight, and concentration and uptake of nutrients (N, P, K, Ca and Mg) were measured. The preliminary evaluation of the diagnostic tests for assessing the N status of the wheat plant were conducted by comparing the relative sensitivity of the above parameters to the different rates of applied N. First approximations of the critical levels were estimated from graphs of grain yield against the various analytical measurements. The application of N increased grain yield, dry matter production, the concentration of nitrate-N, N, P and K in the plant tops. The application of 200 pounds of N per acre decreased the test weight and increased the protein content of the grain. This same rate of N fertilization produced an increase in the number of culms per foot of drill-row and the plant leaf percentage. The concentration of nitrate-N, total N, P, K, Ca, and Mg in the plant tops decreased with time irrespective of N treatment as the plants matured. The concentration of nitrate-N in the upper leaves was greater than the concentration of nitrate-N in the lower leaves at the boot stage of growth. The total uptake of these nutrients with time corresponded to increases in yield of dry matter. A suitable approach for assessing the N status of the wheat plant appeared to be that of measuring the level of total N in the plant tops or the level of nitrate-N in the plant leaves during the latter part of April. At this time the critical level for total N in the plant tops was about 2.8% and the critical level for nitrate-N in the plant leaves was about 300 parts per million. Greater precision was attained in the measurement of total N concentration in plant tops than for the concentration of nitrate-N in the leaves. The critical-level approach for dry matter production, culms per foot of drill-row, and leaf percentage appeared to have limited value for assessing the N status of the wheat plant. Title: Effects of residual and applied nitrogen on Nugaines wheat Author: Laopirojana, Pojanee A study was made to evaluate the effect of different rates of N fertilization on Nugaines wheat. The variable N treatments provided different N regimes as a basis for evaluating potential diagnostic tests for assessing the N status of the wheat plant. The crop was grown in Lane county during the 1968 growing season on soil of the Malabon. series. To evaluate the treatment effects the yield of grain and dry matter, number of culms per foot of drill-row, leaf percentage, grain protein, test weight, and concentration and uptake of nutrients (N, P, K, Ca and Mg) were measured. The preliminary evaluation of the diagnostic tests for assessing the N status of the wheat plant were conducted by comparing the relative sensitivity of the above parameters to the different rates of applied N. First approximations of the critical levels were estimated from graphs of grain yield against the various analytical measurements. The application of N increased grain yield, dry matter production, the concentration of nitrate-N, N, P and K in the plant tops. The application of 200 pounds of N per acre decreased the test weight and increased the protein content of the grain. This same rate of N fertilization produced an increase in the number of culms per foot of drill-row and the plant leaf percentage. The concentration of nitrate-N, total N, P, K, Ca, and Mg in the plant tops decreased with time irrespective of N treatment as the plants matured. The concentration of nitrate-N in the upper leaves was greater than the concentration of nitrate-N in the lower leaves at the boot stage of growth. The total uptake of these nutrients with time corresponded to increases in yield of dry matter. A suitable approach for assessing the N status of the wheat plant appeared to be that of measuring the level of total N in the plant tops or the level of nitrate-N in the plant leaves during the latter part of April. At this time the critical level for total N in the plant tops was about 2.8% and the critical level for nitrate-N in the plant leaves was about 300 parts per million. Greater precision was attained in the measurement of total N concentration in plant tops than for the concentration of nitrate-N in the leaves. The critical-level approach for dry matter production, culms per foot of drill-row, and leaf percentage appeared to have limited value for assessing the N status of the wheat plant. Close