Nonstructural carbohydrate and element pools in globemallow (Sphaeralcea): defoliation effects and seasonal trends

Globemallows (Sphaeralcea spp.) are arid land forbs suitable for seeding with crested wheatgrass (Agropyron cristatum [L.] Gaertner). However, little is known about the quantitative role of total nonstructural carbohydrates (TNC) in relation to globemallow tolerance of grazing, or about seasonal dynamics of mineral elements. The objectives of this study were to compare TNC and element pools (concentration x biomass) in the roots, crowns, and shoots of clipped versus unclipped S. munroana (Dougl.) Spach. Seedlings of S. munroana were transplanted to a northern Utah field site in 1985. Interplanted crested wheatgrass provided a uniform competitive background. One-half of the globemallows were clipped to 5 cm on 10 May 1986 when stems were elongating and root and crown TNC pools were low. The remaining globemallows were not clipped. Root, crown, and shoot pools of TNC and elements (N, P, K, Ca, and Mg) were determined on 1 May, 20 May, 7 June, 11 July, 22 September, and 5 November 1986, and 29 May 1987. Defoliation did not affect shoot weights during a 1-year period. Experiment-long TNC and element pools also were not affected by clipping. Results indicate that S. munroana shoot recovery from a single spring grazing during a 1-year period would not be impaired by low root and crown TNC pools, and that TNC stored in the roots and crowns would account for only 7% of the regrowth produced. Furthermore, TNC and element pools of roots and crowns were generally constant from May to September but increased from September to November. TNC and element pools in shoots increased from May to September and then generally declined by November. TNC pools of roots and crowns declined during winter

Survival and growth of globemallow [Sphaeralcea] species in dry land spaced-plant nurseries

Globemallows (Sphaeralcea spp.) have potential in rangeland seedings. Thirty-seven accessions of globemallow were grown at 2 sites in northern Utah and southern Idaho to quantify their agronomic attributes. Data for transplant survival, standing crop, and seed yield were collected in 1987 and 1988. Total globemallow survival (mean = 92%) and seed weights (mean = 0.8 g/plant) differed significantly (P is lesser than or equal to 0.05) among locations. Plant weight (mean = 102 g/plint) differed significantly (P is lesser than or equal to 0.05) among locations, species (S. grossulariifolia, S. coccinea, S. parvifolia, S. munroana, and interspecific hybrids), and years. In a second study, 5 globemallow accessions of 2 species and ‘Spredor 2’ alfalfa (Medicago sativa) were grown with ‘Hycrest’ crested wheatgrass (Agropyron desertorum X A. cristatum) to determine forage yields from 1985-1988. Globemallows produced significantly (P is lesser than or equal to 0.05) less forage (62 g/ml) than alfalfa (389 g/m2). Forage yield of S. munroana (76 g/m2) did not differ significantly (P>0.05) from that of S. grossulariifolia (48 g/m2). Forage yield of crested wheatgrass (mean = 101 g/m2) did not differ significantly (P>0.05) when grown with globemallow versus alfalfa. Plant breeding and selection could probably improve these agronomic attributes for globemallows seeded on rangelands.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Globemallows

This material was digitized as part of a cooperative project between the Society for Range Management, the National Agricultural Library, and the University of Arizona Libraries.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202

Interplanting Crested Wheatgrass with Shrubs and Alfalfa: Effects of Competition and Preferential Clipping

Planting palatable shrubs and legumes into an established stand of crested wheatgrass (Agropyron desertorum and A. cristatum) could increase forage yield and nutritional quality. Preferential grazing of the grass and legume in spring may enhance establishment of shrub seedlings. Seedlings of 3 species of shrubs (Artemisia tridentata ssp. vaseyana, Kochia prostrata, and Atriplex canescens) were transplanted into plots of crested wheatgrass using a replacement series design. Each species of shrub was grown with the grass, and with the grass and alfalfa (Medicago sativa cv. \u27Ladak\u27); each of the 5 species was also grown in monoculture. Swards were either uncut or the grass and alfalfa were clipped while actively growing in late May and early June. Shrubs had greater current annual growth (CAG) (P≤0.001), higher relative yields (P≤0.05), lower mortality (P≤0.001), and more inflorescences (P≤0.001) in monoculture than in mixture. The grass had greater CAG in mixture than in monoculture (P≤0.05), and the grass and alfalfa had greater relative yield in mixture than in monoculture (P≤0.05). Clipping crested wheatgrass and alfalfa increased shrub CAG (P≤0.01), reduced mortality (P≤0.001), and increased the number of inflorescences (P≤0.01), but the increase in shrub CAG and flowering due to clipping was not as great as when shrubs were grown in monoculture. There were no interactions between competition and clipping (P\u3e0.05). In terms of CAG, mortality, and flowering, A. tridentata grew better than K. prostrata, which grew better than A. canescens, but these relationships involved complex interactions. The contribution of shrubs to the biomass in mixture was minor; although alfalfa dominated three-way mixture yields, the grass also made a substantial contribution. Since competition was more important in determining shrub response than clipping and the 2 effects were independent, it is probably more important to reduce interspecific competition than to modify grazing practices when planting shrubs in a crested wheatgrass stand

Machinery Maintenance

This material was digitized as part of a cooperative project between the Society for Range Management, the National Agricultural Library, and the University of Arizona Libraries.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202

Determination of root mass ratios in alfalfa-grass mixtures using near infrared reflectance spectroscopy

Hand separation of roots of 2 or more plants species from soil cores is a tedious and labor-intensive task. Our objective was to determine whether near-infrared reflectance spectroscopy (NIRS) could be employed to estimate root biomass proportions in binary mixtures of alfalfa (Medicago sativa L.) with each of 4 grasses. Grasses chosen for experimentation were crested wheatgrass (Agropyron cristatum L.), intermediate wheatgrass [Thinopyrum intermedium (Host) Barkworth & D.R. Dewey], an intergeneric hybrid [Elytrigia repens (L.) Nevski × Pseudoroegneria spicata (Pursh) Love], and Russian wildrye [Psathyrostachys juncea (Fisch.) Nevski]. In the first experiment, roots from single-species field plots were washed from soil cores, dried, ground, and mechanically mixed in preselected alfalfa-grass ratios in which the percentage of grass varied from 0 to 100. Equations to measure the proportion of alfalfa or grass were developed from near infrared reflectance data using 84 randomly selected samples. In the second experiment, the 5 plant species were grown in greenhouse pots in pure stands and in binary mixtures that included all combinations of the grasses. Root systems were separated while attached to the topgrowth, dried, and ground. Tissues from single species treatments were mixed and calibration equations developed from these mixtures were used to estimate the proportion of alfalfa and the proportion of grass in samples. Samples contained either one type of root or a mixture of roots in proportions similar to those that occurred naturally in the pots. Coefficients of determination (r2) between the estimated and the actual root mass ratios ranged from 0.92 to 0.99. Determination of the proportion of grass in the samples was more accurate and precise than determination of the proportion of alfalfa. After the appropriate calibration equations have been developed, NIRS is more efficient than hand separation for estimating alfalfa-grass root mass ratios. The utility of the techniques can be increased by developing equations that encompass more complex mixtures and a wider range of environmental circumstances.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Utilization of globemallow (Sphaeralcea) taxa by sheep

Globemallows (Sphaeralcea spp.) are well adapted to semiarid and arid environments. They are potentially useful as the forb component of seeding mixtures for rangeland improvement in the western states. However, the degree of acceptability of globemallow forage to livestock has not been well established. We tested 13 globemallow accessions representing 4 species and compared their utilization by sheep (Ovis aries) with that of crested wheatgrass [Agropyron cristatum (L.) Gaertn. X A. desertorum (Fisch.) Schult.] and alfalfa (Medicago sativa L.) during fall 1988 and 1989, and spring 1990 and 1991. Alfalfa consistently produced more forage per plant than wheatgrass or globemallows, and a greater portion of the alfalfa was eaten than of the other species. Sheep utilized wheatgrass more than globemallows in the fall, but the converse was true during spring pasturing. Over the 4 years, sheep ate similar proportions of wheatgrass and individual globemallows. The percentage of S. coccinea (Pursh) Rydb. forage consumed equaled that of crested wheatgrass or alfalfa in the fall but did not equal the percentage of alfalfa consumed in spring. However, S. coccinea produced much less total forage than the other species evaluated. Pre-grazing plant dry weight, dry matter content, and the occurrence of rust caused by Puccinea sherardiana Korn were negatively associated with globemallow utilization. Over-winter mortality of grazed globemallow exceeded that of ungrazed plants. Crested wheatgrass and alfalfa stands were not reduced by grazing. Globemallows are acceptable, but not highly preferred, forbs which can be seeded in environments where alfalfa and other more desirable species are not adapted.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Element concentrations in globemallow herbage

Globemallows (Sphaeralcea spp.) are native, drought-resistant forbs of interest for inclusion in seed mixtures for semiarid rangeland renovation. Little is known of their nutritional value for ungulates. We measured element concentrations in representative globemallow species and evaluated their adequacy for livestock nutrition. We also correlated forage selection by sheep (Ovis aries) with element concentrations. Alfalfa (Medicago sativa L.), crested wheatgrass [Agropyron cristatum (L.) Gaertn. X A. desertorum (Fisch.) Schult.], and 13 accessions of globemallows [S. coccinea (Pursh) Rydb., S. grossulariifolia (H. & A.) Rydb., S. munroana (Dougl) Spach., and S. parvifolia A. Nels.] were transplanted into replicated grazing trials in southern Idaho. Herbage was sampled and the pastures were grazed by sheep in the fall of 2 years and in the spring of the following 2 years. Concentrations of Ca and Mg in crested wheatgrass were lower than in forbs. Differences between seasons were greater than the differences among globemallow species. Forage selection ratios were positively associated with the N concentration of globemallow leaves and with the Ca:P ratio of globemallow stems but were negatively associated with stem Zn concentrations. Herbage from pastures containing crested wheatgrass with globemallows and/or alfalfa would meet the dietary element requirements of beef cattle (Bos taurus) and sheep.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Nonstructural carbohydrate and element pools in globemallow (Sphaeralcea): defoliation effects and seasonal trends

Globemallows (Sphaeralcea spp.) are arid land forbs suitable for seeding with crested wheatgrass (Agropyron cristatum [L.] Gaertner). However, little is known about the quantitative role of total nonstructural carbohydrates (TNC) in relation to globemallow tolerance of grazing, or about seasonal dynamics of mineral elements. The objectives of this study were to compare TNC and element pools (concentration x biomass) in the roots, crowns, and shoots of clipped versus unclipped S. munroana (Dougl.) Spach. Seedlings of S. munroana were transplanted to a northern Utah field site in 1985. Interplanted crested wheatgrass provided a uniform competitive background. One-half of the globemallows were clipped to 5 cm on 10 May 1986 when stems were elongating and root and crown TNC pools were low. The remaining globemallows were not clipped. Root, crown, and shoot pools of TNC and elements (N, P, K, Ca, and Mg) were determined on 1 May, 20 May, 7 June, 11 July, 22 September, and 5 November 1986, and 29 May 1987. Defoliation did not affect shoot weights during a 1-year period. Experiment-long TNC and element pools also were not affected by clipping. Results indicate that S. munroana shoot recovery from a single spring grazing during a 1-year period would not be impaired by low root and crown TNC pools, and that TNC stored in the roots and crowns would account for only 7% of the regrowth produced. Furthermore, TNC and element pools of roots and crowns were generally constant from May to September but increased from September to November. TNC and element pools in shoots increased from May to September and then generally declined by November. TNC pools of roots and crowns declined during winter

Liquid crystal quenched orientational disorder at an AFM-scribed alignment surface

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