bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Fallow‐Farming Systems in Semi‐Arid Africa Using a Model to Simulate the Hydrologic Budget1
Authors: Hall Anthony E. , Dancette Claude
Published: July 2010

A model was developed to predict bare soil evaporation, crop water use, and the distribution of water in the soil. Comparisons with hydrologic budget data obtained in the field with bare soil, cowpeas (Vigna unguiculata (I.,) Walp.), and millet (Pennisetum typhoides (Burm. f.) S. and W.) indicated that the models performed adequately for the conditions and objectives of the study. Simulations of annual fallow, predicted that the amounts of water conserved in the soil would rapidly decrease with decreases in annual rainfall. Simulations of partial year fallow, achieved by weed removal after harvest of 90‐day or 75‐day millets were evaluated through an 8‐ year period of wet, dry, wet, and dry years having an average, monomodal rainfall of 502 mm. The simulations predicted that substantial quantities of water may be conserved in the soil by partial fallow during wetter years. More soil moisture would be conserved with the shorter cycle variety, but the longer cycle variety would have greater need for this moisture in this climatic zone during dry years, indicating a possible advantage of rotations involving short cycle, and long cycle crops. Shorter cycle varieties and partial fallow could also increase ground water recharge. The simulations predicted that present varieties may only use a small proportion of the moisture that may be stored below 150 cm depth in the soil by partial fallow, indicating a possible need for developing varieties with faster growing, deeper, root systems.
Intake of Dairy Heifers Fed Mixed Crownvetch‐Tall Fescue Hays Harvested in May and July1
Authors: Burns J. C. , Mochrie R. D. , Cope W. A.
Published: July 2010

Dry matter yield per hectare has been increased, compured to a pure stand of crownvetch, by growing a cool season grass in mixture with crownvetch (Coronilla varia L,). The objective of this study was to determine if the presence of tall fescue (Festuca arundinacea Schreb.) in several proportions relative to crownvetch would alter dry matter intake of Holstein heifers. Four hays were evaluated. Two were May‐harvested hays and consisted of 87% crownvetch and 13% tall fescue (M‐87) and 28% crownvetch and 72% tall fescue (M‐28). The other two hays were harvested in July and consisted of 78% crownvetch and 22% tall fescue (J‐78) and 80% crownvetch and 20% tall fescue (J‐80). Although dry matter intake (kg/100 kg of body weight) differed significantly (P ≤0.05) among hays, no significant difference resulted from the predominance of tall fescue in the W‐28 hay compared with the M‐87 hay (2.68 vs. 2.59). Consumption of the M‐87 hay was significantly higher than the mean of the J‐78 and J‐80 hays (2.59 vs. 2.32). Also, consumption of the M‐28 hay was higher than the mean of the J‐78 and J‐80 hays (2.68 vs. 2.32). The differences in dry matter intake of the latter two comparisons were consistent with forage quality estimates. The practice of growing a cool season grass with crownvetch to enhance dry matter production was not detrimental to dry matter intake of May‐harvested hay in this study. However, hay harvested in July was inferior to hay harvested in May even though the latter was predominantly crownvetch. Further consideration must be given to digestibility of such mixtures and their relationship to animal gain.
Triazine Persistence in Soil in Eastern Ohio1
Authors: Nearpass D. C. , Edwards W. M. , Taylor A. W.
Published: July 2010

Degradation rates of triazine herbicides, following application for weed control, were measured to evaluate their persistence in Eastern Ohio soils under no‐tillage and conventional corn management systems.

Atrazine [2‐chloro‐4(ethylamino)‐6‐isopropylamino‐s‐triazine] degradation in the field was compared with that found in laboratory measurements on the same soil. The reaction showed first‐order kinetics, but in the field the rate constant varied being faster in summer and slower in the early fall. Simazine [2‐chloro‐4,6‐bis‐(ethylamino)‐s‐triazine] degradation in the field showed similar characteristics. Under conventional and no‐till managements both chemicals degraded through three or four half‐lives during the 160‐day growing season. Under similar pH conditions, the presence of a surface mulch did not affect the degradation rate.
Nitrogen Fertilization of Irrigated Russian‐Thistle Forage. II. Some Nutritional Qualities1
Authors: Hageman J. H. , Fowler J. L. , Schaefer D. A.
Published: July 2010

Russian‐thistle (Salsola spp.), a widely dispersed weed of the western U.S., has been used occasionally as an emergency forage during periods of drought. Because of its known water use efficiency and the growing demand upon irrigation water resources, several of the nutritional qualities of Russian‐thistle have been examined under irrigated field conditions to evaluate its potential as a forage crop for arid and semiarid regions. Plants were grown in the field with a total water application of 22 to 28 cm: urea levels corresponding to 0, 28, 56, 112, and 224 kg N/ha were applied. Water content was found to be similar to that of other species commonly used as forage and was minimally affected by N application. Crude protein, acid detergent lignin, and acid detergent fiber content were slightly but significantly affected by N application. These latter three parameters, however, varied strongly with stage of maturity. Average values of crude protein, acid detergent lignin, and acid detergent fiber were 22, 20, and 4%, respectively, for the youngest plants and 10, 33, and 7%, respectively, for the oldest plants. The protein had an amino acid composition which was nutritionally well balanced. At 112 and 224 kg N/ha plants had average nitrate levels of 0.5 to 0.6%, although variability in measured levels was large.
Portable Electronic Field Scale1
Authors: Engelke M. C. , Campbell E. C.
Published: July 2010

A newly developed portable electronic field scale reduces labor and increases efficiency and precision in collecting field data. The scale consists of a low profile platform transducer, with a 1200 cm2 surface area, and a digital weight recorder. It is powered by eight nickel‐cadmium batteries and is programmed to store up to 14 tare weights, provide continuous visual display of the data, and average several weights per second over 1, 2, 4, or 8 sec for increased precision. Identification (ID) and data can be entered by keyboard. A manual record command from the keyboard prints the ID and data on paper tape and records it on cassette tape. The cassette tape can be used for storing and transferring data to computers for further analysis. Utility and precision of the scale are described.
Amino Acid Scores of Dry Bean Proteins Fractionated by Deae Cellulose1
Authors: Vigue J. T. , Marsh H. V. , Pellett P. L.
Published: July 2010

Dry bean (Phaseolus vulgaris L.) are an additional source of protein for human consumption, but the crop has never been exploited as a protein source. The objective of this study was to determine if dry beans exhibit a wide range of sulfur amino acids in proteins fractionated by DEAE chromatography. Protein was extracted from two cultivars (‘Sanilac’ and ‘Bush Blue Lake 290’) and one genotype (P.I. 136‐691) of dry beans with phosphate buffer and fractionated. The amino acid scores of each protein fraction were calculated, based upon the estimated amounts for human needs. The sulfur amino acid scores varied from 19 to 184. Three protein fractions from P.I. 136‐691 had sulfur amino acid scores greater than 100. Lysine scores ranged from 101 to 187 with most being 140 or greater. Threonine scored below 99 in three fractions. Valine and leucine scored below 100 in one of 15 protein fractions analyzed. Isoleucine, tyrosine, and phenylalanine were never limiting in these isolated proteins. Although the phosphate extract contained about 50% of the total bean N, the protein fractions from the DEAE cellulose columns represented too small a fraction of total bean protein, (−0.5 to 7 mg/g dry wt. of bean) to be useful for screening potential genotypes for breeding.
A Versatile and Economical Tractor‐Mounted Soil Sampler1
Authors: Chandler J. M. , Savage K. E.
Published: July 2010

A hydraulic soil coring machine was constructed for obtaining samples for herbicide residue studies in cotton (Gossypium hirsutum L.) and soybean [Glycine max (L.) Merr.] field plots throughout the growing season. The device is mounted on the three‐point hitch of a tractor and utilizes a conventional hydraulic cylinder for taking the soil core. The sampling unit moves laterally on a rigid frame, allowing collection of samples at any point up to 75 cm from the center line of the tractor. Samples may be taken to a depth of 50 cm in 5‐cm increments. The simplicity of design and economical construction, along with the ease of mounting on the tractor, make this an excellent research tool.
Temperature Gradient Effects on in situ Hygrometer Measurements of Soil Water Potential. II. Water Movement1
Authors: Wiebe Herman H. , Brown Ray W.
Published: July 2010

Temperature gradients can cause serious errors in soil water potential determinations by in situ thermocouple hygrometers. One source of error in thermally unstable soil could be condensation or soil drying at the hygrometer caused by temperature induced water movement. In a laboratory study we imbedded various types of hygrometers in sieved loam soil (skeletals, mixed, frigid Lithic Calciorthid Aredisol) and measured temperature gardients and water movement near the hygrometers while the surrounding soil was subjected to temperature gradients. Greatest condensation or drying occurred at the sample surface of end window units while cylindrical sample surface units permitted through diffusion with minimum condensation. Greater heat conduction within hygrometers was correlated with steeper thermal gradients in adjacent soil and with greater water movement. Construction of metals, with large lead wires, and large hygrometer size contributed to greater thermal gradients and water movement in adjacent soil. Hygrometers are relatively insensitive to temperature gradient errors if they are constructed with cylindrical sample surface geometry, with concentric placement of the measuring junction, of materials having low thermal conductivity, with small guage lead wires, and small size.
Cultivar Characteristics of Ethephon‐treated Kentucky Bluegrass1
Authors: Nittler L. W. , Kenny T. J.
Published: July 2010

Even though several characteristics useful for testing Kentucky bluegrass (Poa pratensis L.) for cultivar purity have been identified, additional characteristics are needed for distinguishing similar cultivars. The investigation reported here was conducted to determine if cultivar differences not observable on untreated plants would develop in response to ethephon (2‐chloroethylphosphoric acid) treatment. Seedlings grown with sand‐nutrient culture under continuous light were sprayed three times (at 3‐day intervals) with 1,000 ppm ethephon solution. Plants were evaluated 52 days after seeds were planted (28 days after the first ethephon application). By this time stems had elongated, leaf blades were very short, red pigment development was different from that of untreated plants and crown type of some cultivars was modified by ethephon. Stems of ‘Windsor’ averaged 82 mm in length compared to 150 mm for ‘Victa’. Leaf blades of Windsor averaged 4 mm in length compared to 18 mm for ‘Park’. ‘Parade’ had the most plants with spreading or semispreading crowns and Windsor had the fewest. Treated plants of most cultivars had less red leaf sheath color than untreated plants but ethephon increased differences between certain cultivars in this regard. Some treated plants had small red areas at nodes only. ‘Touchdown’ had the most plants of this type and ‘Fylking’ had the fewest. Ethephon treatment, by inducing cultivar differences not observable on untreated plants, provides another useful tool for testing Kentucky bluegrass seed lots for cultivar purity.
Yields and Protein Content of Wheat Grain as Affected by Cultivar, N, and Environmental Growth Factors1
Authors: Terman G. L.
Published: July 2010

Grain protein is important in human and animal nutrition and in relation to various culinary uses of flour. Various wheat (Triticum aestivum L.) cultivars are reported to vary widely in grain yield and protein concentrations. To study yield‐protein relationships, three soft red winter (Atlas 66, Knox 62, and Blue Boy) and three hard red winter (Norin 16, Tascosa, and Omaha) wheat cultivars were grown in a pot experiment at Muscle Shoals, Alabama. Response to 0, 100, 200, 400, 800, and 1,200 mg of N/pot (3 kg of Mountview silt loam) together with adequate, uniform rates of other nutrients was determined.

All cultivars increased similarly in grain and straw yields, crude protein concentrations, and crude protein / pot with amount of applied N. The ranking for grain yields was: Tascosa > Blue Boy = Knox 62 > Omaha > Norin 16 > Atlas. The ranking for crude protein concentrations was in the reverse order. These trends indicate pronounced genetic differences among cultivars. At each rate of applied N, protein concentrations were also inversely related to grain and straw yields. Early uptake of N at forage and boot stages of growth was usually highly correlated with uptake in grain + straw at maturity. Nitrogen and moisture supply, light, temperature, and other growth factors greatly affect yield‐protein relationships among cultivars. Differences among cultivars tended to be greatest under optimum growth conditions.
Acceleration of Boll Dehiscence with Desiccant Chemicals1
Authors: Cathey George W.
Published: July 2010

Maturity of cotton (Gossypium hirsutum L.) plants is sometimes delayed and some top bolls may not have opened by the first hard freeze in the fall. The result is often a significant economic loss to the grower. The objectives of this research were to investigate the drying pattern in cotton bolls during the final stage of development and to evaluate the effects of desiccant‐type harvest aid chemicals in altering the boll drying process and dehiscence rate. One greenhouse study was conducted to measure moisture loss from the bur and seed cotton fractions of treated and untreated bolls during the final stage of maturity. Two field studies were conducted to determine the effects of desiccant chemicals on yield components, fiber properties, and dehiscence rate of bolls that developed late in the growing season. The greenhouse plants were sprayed with 187 liters/ha of a 1.5% aqueous solution of arsenic acid and those in the field were sprayed with either sodium chlorate, paraquat, or arsenic acid at 6.72, 0.14, and 5.39 kg/ha, respectively.

Drying of untreated greenhouse‐grown cotton bolls prior to dehiscence occurred primarily in the interior or seed cotton fraction of the boll. Moisture content of the bur remained at near 80% until just before dehiscence, whereas that of the seed cotton fraction declined at a near linear rate from 78% in 38‐day‐old bolls to 53% in 50‐day‐old bolls. Moisture loss from both fractions was accelerated by treatment of the bolls with arsenic acid, but the loss was more pronounced in the bur than in the seed cotton fraction. Boll dehiscence on field‐grown plants in 1975 and 1976 was influenced by the environment. The dehiscence rate during both years, however, was accelerated in plots treated with either arsenic acid or paraquat. A trend toward increased dehiscence occurred also in the sodium chlorate plots, but the differences were significant during 1975 only. Dehiscence in the arsenic acid plots was greater than in any of the other plots during both years. None of the chemicals had any adverse effects on any yield component or fiber property. This research indicates that desiccant‐type harvest aid chemicals can be used to increase the percentage of bolls harvested from a late developer crop without loss of fiber and seed quality.
Spectral Distribution of Dimmed HID Lamps in a Plant Growth Facility1
Authors: Bingham G. E. , Coyne P. I.
Published: July 2010

A commercial dimming ballast system for high intensity discharge (HID) lamps has been tested for use in plant growth chambers. The dimming ballast system can be controlled either manually at the dimming panel or by a d.c. voltage from a programmer or computer. Using the dimming system, photosynthetically active radiation can be continuously varied from about 200 to about 2000 µE m−2s−1. This paper shows the effects of dimming on the spectral intensity (400 to 750 nm) of three types of HID lamps measured individually and in combination to achieve a better spectral mix. The lamps used in this study were 400 w metal halide, mercury vapor and high pressure sodium.
Accumulation of NO3 and NH4 in Reed Canarygrass1
Authors: Gomm F. B.
Published: July 2010

Recent investigations have shown that reed canarygrass (Phalaris arundinacea L.) contains chemical compounds implicated with low palatability, reduced gains, and deaths in cattle. The purpose of this study was to investigate the effects of environmental variables on the accumulation of NO3 in reed canarygrass. An understanding of the response of this species to its environment will aid in the management and culture of reed canarygrass for production of livestock. Reed canarygrass clones were grown in sand‐filled pots in a growth room under the following controlled conditions: temperature, 15 and 30 C; irradiance, 4.2 and 42.0 W/m2; soil moisture, low medium, and saturated; fertilizer‐N, 0, 110, 220, and 440 kg/ha. The clones were cut from meadow sod where the soil, tentatively classified as Silvies series, was Fluventic and Cumulic Haplaquoll‐fine‐silty, mixed, mesic family. Herbage yields and accumulations of NH4‐N and NO3‐N at the end of three growing periods were evaluated. Increasing temperature from 15 to 30 C increased the rate of growth for plants receiving 42.0 W/m2. Yields were highest when plants were grown in saturated soil at 30 C with 42.0 W/m2 and 440 kg N/ha. Concentrations of NH4 and NO3 were highest in plants grown in unsaturated soil at 30 C with 4.2 W/m2 and 440 kg N/ha. When reed canarygrass was grown under these conditions, the NO3‐N concentration increased to 2.43%, 10 times the level (0.21%) considered potentially toxic to livestock.
Time and Rate of Paraquat Application for Curing Meadow Vegetation for Winter Grazing1
Authors: Sneva Forrest A. , Gomm F. B.
Published: July 2010

Winter grazing of paraquat (1,1 dimethyl‐4,4 bipyridinium ion)‐cured meadow vegetation has been shown to hold potential as an alternative to the conventional cut‐stack‐feed practice in the Great Basin meadowlands. Additional information was needed to define (i) the minimum levels of paraquat required for curing; (ii) the best application time; (iii) the comparative effectiveness of above‐canopy spray release with within‐canopy spray release.

Plots were treated with paraquat at rates from 0.06 to 0.56 kg/ha in July of 2 years. Paraquat applied in the morning, midday, and evening hours evaluated plant maturity, illumination, temperature, relative humidity, and surface soil moisture in relation to the chemical's effectiveness to arrest the loss of herbage N.

Vegetation was satisfactorily cured with 0.11 kg/ha paraquat. Crude protein concentrations of meadow vegetation exceeded 7% in July, and treatments in that month maintained concentrations above 5.5% for 160 days; naturally cured vegetation then contained less than 4%. Yield losses in treated plots 90 days after treatment ranged from 22 to 30% but were no greater than those in control plots. Dispensing the spray above the canopy was more efficient than dispensing it within the canopy, but the difference is believed to be a result of poor spray coverage from the within‐canopy treatments. Morning, midday, and evening applications did not produce significantly different treatment means. Crude protein concentration was higher in vegetation treated on sunny days than on overcast days, but this was due to sunny day effect rather than an increase in effectiveness of paraquat. Paraquat residue at 100 days after treatment at the rate of 0.34 kg/ha or less ranged from 3 to 15 ppm.
Tolerance of Desiccation in Germinating Seeds of Crested Wheatgrass and Russian Wildrye1
Authors: Hassanyar Amir S. , Wilson A. M.
Published: July 2010

Inadequate rainfall and drying of soil frequently result in the desiccation of seeds during the interval between planting and germination. Early investigations suggested that crested wheatgrass [Agropyron desertorum (Fisch., ex Link, Schult.)] may be more tolerant of desiccation than Russian wildrye (Elymus junceus Fisch.) at the stage in which the seminal primary root is just beginning to protrude from the caryopsis. The objective of this study was to determine whether these species differ in tolerance at earlier stages of germination.

Three sequential steps were accomplished in a germinator or plant growth chamber: a) an initial wet treatment in which germination of seeds progressed to either the early, the intermediate, or the advanced stage; b) a 4‐day stress treatment at various water potentials; and c) a germination or growth test conducted under favorable moisture conditions to evaluate the effects of temporary stress. Seeds were more susceptible to injury in the intermediate and advanced stages of germination than in the early stage. In the advanced stage of germination, temporary stress injured Russian wildrye more than crested wheatgrass. Water stress delayed and inhibited root growth more than shoot growth. Because inhibition of root development may adversely affect the subsequent growth and survival of seedlings, cultural practices are needed to reduce the severity of water stress at planting depth on semiarid lands.
Uptake of Sulfur by Bentgrass Putting Green Turf1
Authors: Goss Roy L. , Brauen Stanton E. , Orton S. P.
Published: July 2010

Putting green bentgrass (Agrostis spp.) fertility management may vary extremely between geographic locations, especially with respect to N application rates. Rates may vary from 160 to over 890 kg N/ha per year. Tissue removed by mowing over a period of time can cause nutrient deficiency from any nutrient required for growth and development. This field study was conducted on an established Agrostis tenuis Sibth. ‘Astoria’ bentgrass putting green turf at Washington State University's Western Washington Research and Extension Center at Puyallup, WA, to measure plant uptake of S at various rates of applied N and their effects on growth and color. Rates of 0, 56, and 168 kg of S/ha per year from wettable S, and 293, 586, and 976 kg of N/ha per year from urea were applied to plots. Leaf tissue samples were collected over a 12‐month period and analyzed for S by x‐ray fluorescence spectrography. Significantly lower S concentrations were found in tissue from high N plots with zero S as compared to all other treatments. Average tissue S concentrations from nonfertilized plots was lower than it was in tissue receiving N plus S, but tissue S concentrations from nonfertilized plots was significantly higher than in tissue from plots receiving N only. There was no significant difference between average tissue S concentrations among high and low S treated plots in the presence of N. The total S removed in clippings from plots receiving high N and zero S was 48% greater than that from the control. The addition of either 56 or 168 kg S/ha to N fertilized plots increased total S removal in excess of 115% over no‐S treated plots and the combined addition of N and S increased S removal 219% above the S removed in nonfertilized bentgrass. High N plus S fertilized plots had a yield of 71% more clippings and a 36% increase in average tissue S when compared to plots receiving high N and zero S. These tests revealed that 0.3% S concentration in bentgrass putting green turfgrass appears to be minimal under high N fertilization.
Rice Research Harvesting Techniques with a Small Plot Combine1
Authors: McCauley G. N.
Published: July 2010

Harvesting lowland rice (Oryza sativa L.) research plots has been done primarily by hand‐cutting the grain stalks and carrying the cut material to a stationary thresher for threshing. The manual labor involved in the above operation makes lowland rice plot harvesting an expensive labor‐intensive operation and limits the scope and type of experimental work that can be accomplished.

Recently, a small self‐propelled combine (Suzue model CP730C, Suzue Agric. Mach. Co., LTD, Japan), suitable for harvesting small areas of lowland rice, (modified by replacing the bulk auger with a sample pan) was evaluated for use in harvesting rice research plots. The combine was evaluated for the most effective length of a 0.8 m harvest swath on three cultivars, ‘Labelle,’ ‘Lebonnet,’ and ‘Della.’ Harvest swath lengths evaluated ranged from 1.5 to 12 m in 1.5 m increments. An area 0.4 ✕ 6.0 m was hand harvested as the check. Another area 0.8 ✕ 6.0 m was harvested across the rows to simulate broadcast rice. A harvest swath 1.5 m long gave consistently larger yields than hand‐harvested. Mechanically harvested swaths of 3 to 12 m resulted in similar yields for all cultivars. For ‘Lebonnet’ and ‘Della’ hand‐harvested and mechanically‐harvested swaths greater than 3 m long were similar in yield. Mechanically‐harvested 3 to 12 m swaths of ‘Labelle,’ with the rows gave lower yields than mechanically‐harvested swaths across the rows.
Nitrate Levels in Vegetative and Floral Tillers of Western Wheatgrass and Green Needlegrass as Affected by Nitrogen Fertilization1
Authors: White Larry M. , Halvorson Ardell D.
Published: July 2010

In the northern Great Plains, nitrogen fertilization is one means of increasing forage production in the spring during the cow‐breeding season. Our objective was to determine how much N can be applied without causing toxic quantities of nitrate‐N (>2,080 ppm) in the forage. In late March 1973, ammonium nitrate was applied at 0, 40, 80, 160, 320, and 640 kg of N/ha to adjacent seeded fields of ‘Rosana’ western wheatgrass (Agropyron smithii Rydb.) and ‘Lodorm’ green needlegrass (Stipa viridula Trin.). Plant nitrate levels were determined on 10 and 11 dates during 1973 and 1974, respectively, from late April through October. There was almost a complete removal of soil nitrate from the top 30‐cm of soil by both grasses and a marked accumulation in the 30 to 60‐cm soil depth on N fertilized plots. About 40 kg of N/ha was mineralized each year in the check plots. About 160 kg of the 640 kg of N applied in March 1973 could not be accounted for 2 years after application. N fertilization did not increase forage production in either 1973 or 1974, but added N caused a linear increase in nitrate‐N of both vegetative and floral tillers of both species both years. Floral tillers of green needlegrass fertilized with 640 kg of N/ha contained toxic quantities of nitrate during June and July 1973, but not in 1974. Neither vegetative nor floral tillers of western wheatgrass fertilized with N rates up to 640 kg/ha contained toxic quantities of nitrate at any sampling date during either year. Floral and vegetative tillers of green needlegrass contained 500 to 1,000 ppm more nitrate‐N than did those of western wheatgrass in both 1973 and 1974. If green needlegrass has been fertilized with more than 320 kg of N/ha, it should be tested for toxic quantities of nitrates before it is grazed by or fed to calves.
Turfgrass‐Paver Complex for Intensively Trafficked Areas1
Authors: Shearman R. C. , Kinbacher E. J. , Riordan T. P.
Published: July 2010

Vehicular traffic on turf results in wear injury and soil compaction problems that can result in stand loss and a decline in turf quality. Physical or cultural aspects that protect turfgrass crowns from wear injury also enhance the turf's ability to persist in intensively trafficked areas. This study investigated a concrete‐grid system (turfgrass paver complex) which was designed to protect turfgrass crowns from vehicular wear injury. The study evaluated the influence of this system on establishment, quality, wear injury, and recuperative rate of six turfgrasses.

Six turfgrasses were established in the grass‐paver complex in a silty‐clay‐loam soil (Typic Arguidoll) and were exposed to vehicular wear injury. The complex improved turfgrass wear tolerance and recuperative rate of the grasses with the exception of ‘Merion’ Kentucky bluegrass (Poa pratensis L.). Merion Kentucky bluegrass, ‘Manhattan’ perennial ryegrass (Lolium perenne L.), and ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.) were the most wear tolerant of the grasses tested. ‘Fairway’ crested wheatgrass (Agropyron cristatum Gaertn.) and ‘Highlight’ chewings fescue (Festuca rubra var. commutata Gaud.) had the poorest wear tolerance.

The grass‐paver complex adversely affected turfgrass quality of Manhattan and Merion, but enhanced the quality ratings for Fairway. Winter survival of Manhattan and Kentucky 31 was adversely affected by the paver complex.
Treatment of Growing Sugarbeets with Soil Injected Ethylene1
Authors: Freytag A. H. , Akeson W. R. , Stout E. L.
Published: July 2010

Ethylene is an endogenous plant hormone which influences many aspects of plant growth and development, but its effect upon economic yield of crop plants is not understood well. Our objective was to evaluate the effect of ethylene treatment on sugarbeet (Beta vulgaris L.) roots during the growing period on yield, sucrose content, and purity. Field studies were conducted in 1973, 1974, and 1975 in Colorado, Kansas, Nebraska, Wyoming, Montana, and Ohio. Ethylene was injected 20 cm into the soil between rows at the 11‐leaf‐stage of development. Tests showed that ethylene moves 24 m or more in the soil after injection and so experiments were designed to prevent cross‐contamination of plots. Roots were analyzed for weight, sucrose percent, and clarified juice purity, immediately after harvest in September or October. The effect of ethylene on root and foliage growth was also evaluated in hydroponic studies.

Ethylene increased green and dry weight yields of hydroponically grown sugarbeet roots 38.9 and 42.9%, respectively, over nontreated beets. Treated roots had a higher water content as well as a higher dry matter yield than non‐treated beets. Ethylene also stimulated fibrous root formation in hydroponic solution. Ethylene injected at the rate of 0.25 liter/m of travel in field trials increased root yield 8.2% in 13 paired comparisons in 1973 and 1974, and 7.6% in six comparisons in 1975. The treatments, however, gave 3.3 and 1.5% reduction, respectively, in sucrose content in the respective tests so that the ethylene treatment resulted in no significant increase in sugar yield per hectare. Treatment at rates of 0.125 and 0.50 liter ethylene/m showed similar effects upon root yield and sucrose content but were not statistically significant.

Hydroponic studies demonstrated that ethylene applied to the sugarbeet roots during the growing period can substantially increase dry matter yield. Economic yield increases — sucrose per hectare — were not, however, obtained with ethylene injection in field tests.
Growth and Nutrient Uptake of Sugar Beet Influenced by Application of a Soil Conditioner1
Authors: Sepaskhah A. R. , Moosavi S. A. A. , Kashirad A.
Published: July 2010

Low stability and physical degradation of the surface soil are problems affecting agricultural use of large areas in the arid and semiarid regions. Use of chemical soil conditioners to improve soil physical properties may result in soil fertility problems. This experiment was conducted to study the effects of Krilium Merloam, a copolymer of vinyl acetate and maleic acid (application rates of 0, 0.05, 0.10, and 0.15% dry weight basis of soil), on growth and nutrient uptake of sugar beet (Beta vulgaris L.) and soil structure stabilization in greenhouse conditions. A local cultivar of sugar beet was grown in a Calcixerollic Xerochrept silty clay soil. Plant growth was measured by top and root dry weights. The total N, P, K, Na, Ca, Mg, Fe, Zn, Cu, and Mn in tops and roots were determined. Water stable aggregates of soil were also measured. Significant top growth reduction and most severe leaf chlorosis occurred at the application rate of 0.15%. Root dry weight was not decreased at any application rate. Nitrogen in the tops was reduced with Krilium Merloam application. The decrease of P in the tops at application rates higher than 0.10% was accompanied by an increase in mean weight diameter (MWD) of the soil aggregates. Among the micronutrients reduced Zn and Fe uptake in tops at an application rate of 0.15% possibly resulted in chlorosis of leaves.
Reclamation of Surface‐Mined Coal Spoils in Western Kentucky1
Authors: Powell J. L. , Barnhisel R. I. , Akin G. W.
Published: July 2010

abstract

Revegetation of disturbed land as required by Public Law 95.87 is a difficult task due to the lack of technology and added restrictions that negates the use of past experience utilized under less stringent laws. The objective of this study was to determine the effect of land preparation and of P fertilizer in the reclamation of surface‐ mined coal spoils. Four land preparation treatments were used with three levels of P superimposed on each. The area was seeded to Ky 31 tall fescue (Festuca arundinacea Schreb.) and Kenland red clover (Trifolium pratense L). Good vegetative cover was obtained on plots to which P was applied but, without it, grass and legume plants were stunted. There was a significant forage yield response to P the first harvest year (second growing season). The effect of this single P application diminished with time, and by the fourth growing season P had no effect on yield. The rough micro‐relief produced by ripping (subsoiling) significantly increased yields over those obtained from disking treatments, apparently by creating a micro‐relief which improved water intake and offset the slow infiltration rate of spoil materials. The use of a mulch further increased yields primarily by protecting the surface and maintaining the rough micro‐topography. The influence of ripping diminished with time. At the last harvest, there were no significant differences in yields as the result of land preparation treatments.
In Vitro Fermentation of Forages with Inoculum from Cattle and Sheep Fed Different Diets1
Authors: Horton G. M. J. , Christensen D. A. , Steacy G. M.
Published: July 2010

abstract

Inoculum is the single most important source of variation in in vitro rumen fermentation systems used to predict forage quality. This investigation was carried out to study the effects of donor animal diet and donor animal species on the activity of the inoculum (whole rumen fluid) used in the two stage in vitro fermentation technique for estimating forage digestibility. Two wethers and two steers were fed either wheat straw (Triticum aestivum L.) smooth bromegrass (Bromus inermis Leyss.) alfalfa (Medicago sativa L.) hay (hay) or barley (Hordeum vulgare L.) and dehydrated alfalfa (1:l) pellets (barleydehy) in a double switchback arrangement with three periods of 28 days. Nineteen forages including alfalfa, smooth bromegrass, crested wheatgrass [Agropyron desertorurm (Fisch ex Link) Schult.] and oat (Avena sativa L.), wheat and barley straws were digested in vitro and in vivo by steers. Each substrate was digested in duplicate during three successive periods with inoculum from sheep and cattle consuming each of the three diets.

Donor diet had a significant effect on in vitro dry matter (IVDMD) and acid‐detergent fiber digestibility (IVADFD) with inoculum from sheep and cattle. Values were lowest (P<0.001) with inoculum from animals fed straw and were highest when hay was fed. In vitro digestibilities were higher (P<0.001) with sheep inoculum than with cattle inoculum on straw and barley‐dehy diets; values were highest (P<0.001) with cattle inoculum on the hay diet. Estimates of in vivo digestibility using IVADFD were not significant. Linear regression equations, correlations, and standard errors showed a significant relationship (P<0.01) between in vivo dry matter digestibility and IVDMD for inoculum from both sheep and cattle fed either straw, hay, or barley‐dehy. The best fit of cattle in vivo dry matter digestibility was to IVDMD using inoculum from cattle fed the pelleted barley‐dehy diet (r=0.88; Sy.x, ± 2 2.49; P<0.01).
A Computational Approach for Water Culture1
Authors: Asher J. Ben , Gordon J. M. , Gale J. , Kopel R.
Published: July 2010

Water culture methods for commercial crop production are now under research and development. Experiments have been performed primarily to investigate methods for preparing nutrient solutions. The objective of this study, however, was to develop a physical model for a water culture system. A study of nutrient uptake by egg plant (Solanum melanogena L. var. esculentum) as a function of both the solution and the root system properties in a soiless culture system is presented. The soiless culture system. is mathematically modelled with a one‐dimensional continuity equation for mass flow. The kinetics of nutrient uptake in the root system are treated in analogy with the kinetics of enzyme catalyzed processes. The system parameters are determined from experimental data for the two limiting cases of negligible and near‐total nutrient depletion from the solution. An experimental procedure which is intended both to test the validity of the mathematical model and to investigate better techniques for water culture systems is described. Both experimental anl theoretical results showed a rapid depletion in the system of the nutrient O2, and a more moderate depletion of other nutrients such as nitrate and K ions. The theoretical results can also be used to predict possible combinations of nutrient concentration, length of rows, and rate of water flow which afford optimal operation of the system.
Soybean Yields as Influenced by Peanut Hull Applications1
Authors: Reneau R. B. , Jones G. D. , Lutz J. A.
Published: July 2010

Peanut (Arachis hypogea L.) hulls are a waste product that have potential for increasing crop yields when recycled to agricultural land as a source of nutrients and as a mulching material. This study was conducted to determine if peanut hulls could be applied at disposal rates and simultaneously increase soybean [Glycine max (L.) Merr.] yields as a result of increased nutrients and moisture in the rooting zone of soils that are acid and have a high exchangeable A1 content that restricts the soil volume available for root proliferation. Peanut hulls were applied to a Tatum (Typic Hapludults, clayey, mixed, thermic) silt loam soil at rates of 0, 21, 42, and 84 × 103 kg/ha on unfertilized plots and plots that received 49 kg P and 93 kg K/ha. In 1977, a year of moisture stress, peanut hulls increased the yield of seed by 500 kg/ha and forage by 1,560 kg/ha as a result of increased plant available moisture in the fertilized plots. Moisture in the 15 to 30 cm zone averaged 0.33 mm/cm greater in the peanut hull plots. On the unfertilized plots bean yields increased at a linear rate with each 1,000 kg/ha of hulls producing 21 kg/ha of seeds. This response resulted from an increase in both available P and moisture. In 1978, a year of more optimum moisture conditions, hull application did not increase yields in the fertilized plots. Yields in the unfertilized plots could be described by a second order polynomial and approximately 50 × 103 kg/ha of hulls were required to equal yields produced with fertilizer application. Hulls significantly increased the P concentration in the tissue for both the unfertilized and fertilized plots. The P concentration increased by 0.01% for each 5,000 kg/ha of hulls applied for both the unfertilized and fertilized plots. Application of peanut hulls to soils that restrict root proliferation can supply the nutrients needed for soybean production and create more favorable soil moisture conditions.
Environmental Sensitivity of Acetylene Reduction Activity in Prediction of N Fixation in Soybeans1
Authors: Raper C. David , Patterson Robert P.
Published: July 2010

The rate of acetylene reduction by nodules of legumes often is assumed to be related directly to the actual rate of N2 fixation. This study was conducted to evaluate the relationship between effects of water stress and temperature on acetylene reduction activity and actual N accumulation in soybean [Glycine max (L.) Merrill ‘Hill’]. Nodulated plants were grown in a phytotron at day/night temperatures of 22/18, 26/18, and 30/18 C. The plants, contained in individual pots filled with a peat moss‐vermiculite and gravel media, were watered in the morning with a minus‐N nutrient solution and in the afternoon with deionized water. At the beginning pod stage, a single cycle of leaf moisture stress to −24 bars and recovery was applied to half of the plants at each temperature by withholding water and nutrient solution for four days. Plants were sampled over an 18‐day period beginning on the first day that water was withheld. The relation between rate of N accumulation in the plant and rate of acetylene reduction varied with temperature but was not greatly affected by leaf moisture stress within a temperature. Thus, if acetylene reduction is to be used as an indicator of amount of N2 fixed during growth, the effects of temperature during growth must be considered. However, a change in acetylene reduction may be an adequate indicator of response in N2 fixation to such severe, abrupt stress conditions as the single cycle of moisture stress if temperature is constant.
Absorption and Translocation of Chromium through the Surface of a Soybean Leaf1
Authors: Pickrell D. J. , Ellis B. G.
Published: July 2010

Although Cr is known to be important in animal metabolism, it does not readily translocate through the roots of most plants. The addition of Cr to plant leaves as a spray material is a possible method of increasing the Cr content of plants. The objective of this laboratory study was to determine if Cr would be absorbed by a plant leaf and translocated to other portions of the plant. A single drop containing radioactive 51Cr or 59Fe (for comparison) as ethylenediamine tetraacetic acid (EDTA) was placed over the mid‐rib of one leaf on a soybean [Glycine max (L.) Merr.] plant. Absorption and translocation of the tagged Cr or Fe were followed by radio‐autographs while plants were growing and by counting separated plant parts at the end of the experiment. Both 51Cr and 59Fe were absorbed through the surface of the soybean leaves and translocated throughout the plant, but only small amounts were translocated (4% of absorbed Cr). The absorption and translocation of Cr closely paralleled that of Fe. The results show that soybean plants will absorb Cr through their leaves and translocate it to other portions of the plant but the rate for these processes is relatively slow.
Forage Quality of Adapted Dent and Tropical Flint Corn Grown as a Second Crop1
Authors: Monson Warren G. , Young John R. , Johnson Joseph C.
Published: July 2010

The added insect tolerance of the exotic flint corn or other similar varieties could reduce the risk involved in producing a second crop of corn without detracting from silage quality.
Morphological Development, Yield, and Chemical Composition of Orchardgrass at Several Soil Nitrogen Levels1
Authors: Donohue S. J. , Bula R. J. , Holt D. A. , Rhykerd C. L.
Published: July 2010

The effect of high nitrogen fertilizer applications in prolonging vegetative development has not been reported. This phenomenon, if it exists, would affect the most optimum time of harvest and hence, stand longevity. The effects of N fertilizer at rates up to 1,800 kg·ha−1 (vernalized plants) and up to 2,100 kg·ha−1 (non‐vernalized plants) on yield, morphological development, total N, nitrate‐N (NO3‐N), and fructosan concentration of vernalized and non‐vernalized orchardgrass (Dactylis glomerata L.) plants grown under controlled environments were studied.

Herbage yields increased with applied N up to 600 kg·ha−1 and remained essentially the same over the range of 600 to 1,500 kg N·ha−1. At maximum rates of 1,800 and 2,100 kg N·ha−1, yields were drastically reduced. The number and maturity of floral tillers of vernalized orchardgrass plants was greatest at 600 kg N·ha−1 and least at 1,200 and 1,800 kg N·ha−1 indicating that high N delayed floral tiller production. Foliage burn was noted at 1,800 kg N·ha−1 but not at 1,200 kg N·ha−1.

With unvernalired orchardgrass, little change in vegetative tiller production was observed during the 3‐week period where no N was applied. Where 300 to 1,500 kg N·ha−1 was applied, an increase in tiller production was found from week 1 to 2 followed by a decrease in number of new tillers during the third week. At 1,800 or 2,100 kg N·ha−1, only a few new tillers were produced until the third week of the study.

Percent total N and NOa‐N in herbage increased, in general, with increasing N fertilization up to 1,200 kg N·ha−1. At higher N levels (1,500‐2,100 kg N·ha−1), the percentage of these constituents was essentially the same or lower than that noted at 1,200 kg N·ha−1. Percent fructosan in the stubble was inversely related to N fertilization rate.

Although N fertilization is required for economic forage yields of orchardgrass, excessive N caused severe plant stress and modified plant development that could result in reduced yields and severe stand reduction, particularly if harvested at the improper stage of plant development.
Envirommental and Plant Growth Stage Effects on Composition and Digestibility of Crownvetch Stems and Leaves1
Authors: Jung G. A. , Brann D. E. , Fissel G. W.
Published: July 2010

Crownvetch (Coronilla varia L.) has not been widely used for forage, partly because its forage quality has been reported as poor. Studies were undertaken to determine the effects of different environments and clipping schedules on composition and in vitro digestibility of crownvetch stems and leaves. First growth was sampled from flower bud to seedpod growth stage, and regrowth was sampled in July and September. Identical cutting schedules were used at four field locations in West Virginia for 2 years. Also, in growth chambers, controlled day‐night temperature combinations of 16‐2, 16‐10, 16‐18 C; 21‐2, 21‐10, 21‐18 C; and 38‐2, 38‐10, and 38‐18 C were used to determine temperature effects on herbage comosition. Acid detergent fiber and permanganate lignin levels in crownvetch were influenced differently by environment than were their deposition rates. High leaf ADF and lignin levels were attributed to high light intensities within the crownvetch canopy. Stem ADF averaged 18% higher and leaf ADF 36% higher in first regrowth than in second regrowth. Leaf lignin averaged 67%, higher in fist regrowth than in second regrowth. Leaf lignin levels of crownvetch under controlled temperatures and low light intensities were one‐fourth to one‐half of that in field samples. Maturity effects on ADF and lignin levels were significantly greater at the two locations with higher elevations. The ADF and lignin deposition rates in late spring 1970 averaged three times those in 1969 and were associated with higher rainfall. Cutin level of leaves was 65% higher than that of stems, and maximum levels were obtained either at early or full bloom stage.

In vitro digestibility of crownvetch stems decreased 0.81 percentage points per day from flower bud to early bloom, and thereafter at lower rates. Digestibility of crownvetch stems and leaves of first regrowth (58, 74%) was lower than that of second regrowth (66, 78%). The ADF and lignin levels of stems, but not of leaves, were largely independent of crop yield and were inversely related to digestibility. Prediction of nutritive value of firstcrop crownvetch is far more difficult than of other commonly used legumes