Sand-based turfgrass root zones have limited nutrient retention and water-holding capacity. Peat moss oft en is used to off set these defi ciencies, but peat moss decomposes. Biochar is a co-product of several biofuel production processes used to produce bio-oil. Biochar is stable and could have similar water and nutrient retention impacts as peat moss when mixed in sand-based turfgrass root zones. Th e objective of this research was to evaluate the effi cacy of biochar as a sand-based root zone amendment. Water retention, water infi ltration, creeping bentgrass (Agrostis stolonifera L.) rooting depth, and nutrient evaluation experiments were conducted on six sand and biochar root zone mixtures. At fi eld capacity, sand-based media containing 25% (v/v) biochar retained 260 and 370% more water compared to media containing 5% biochar and a pure sand control, respectively. Saturated hydraulic conductivity (K sat ) of the root zones decreased as biochar concentrations increased. Th e rooting depth of bentgrass was reduced up to 46% at biochar concentrations >10%. Extracted pore water electrical conductivity and dissolved total organic carbon increased as biochar concentrations increased. Nitrogen leaching was reduced as biochar concentrations increased. According to the results, biochar may improve water storage, reduce overall water use, and decrease N fertilizer applications in sand-based turfgrass ecosystems.

Ham and Caldwell (1978) reported that fertilizer P increased soybean production but placement had no Improved P and K management systems for no-tillage soybean significant effect on yield and P uptake. The Ham and [Glycine max (L.) Merr.] may be needed to increase yield and profits. This study evaluated the response of soybean to fertilizer P or K rates Caldwell (1978) paper did not report the tillage system and placement as well as residual and direct fertilization from 1995 used in their study, but two other papers did. Those through 1996. Two K and two P experiments were established on papers reported no yield increases from different P and farmers' fields with 10-yr histories of no tillage. An additional P K fertilizer placement methods under conventional-tillexperiment was conducted on one of Iowa State University's research age systems when soil test levels were high (Ham et al., farms. Treatments on farmers' fields included two rates of P (0 and1973; Rehm et al., 1988). However, at low soil test P 19.5 kg P ha Ϫ1 ) or K (0 and 51 kg K ha Ϫ1 ), placement of fertilizer levels, the largest response was from broadcast fertilizer. (surface broadcast or a subsurface band 5 cm beside and 5 cm belowEarly research in Iowa indicated banding of fertilizers the seed ) and time of fertilizer application. Treatments on the research was equal or superior to broadcasting fertilizers if confarm were similar, except the P fertilizer rates applied were 0, 19, 39,

Starter fertilizer can help improve early‐season corn (Zea mays L.) growth, especially under cool soil conditions, but corn hybrids may differ in their response to starter fertilizer. This study evaluated the response of corn hybrids to complete starter fertilizers applied under no‐tillage, dryland conditions. Nine site‐years of data were collected from 1993 through 1995 at four geographical locations: Doon (NW1) in extreme NW Iowa, Sutherland (NW2) in central NW Iowa, Lewis (SW), and Crawfordsville (SE). The soil types were as follows: NW1— Moody silty clay loam (fine‐silty, mixed, superactive, mesic Udic Haplustolls); SW—Marshall silty clay loam (fine‐silty, mixed, superactive, mesic Typic Hapludolls); SE—Nira silty clay loam (fine‐silty, mixed, superactive, mesic Oxyaquic Hapludolls); and NW2—Primghar silty clay loam (fine‐silty, mixed, superactive, mesic Aquic Hapludolls). Each hybrid was planted with and without starter fertilizer applied 2 in. to the side and 2 in. below the seed at planting. Hybrid‐by‐starter interactions were not significant for early‐season dry matter production, nutrient concentration, or grain yield in any of the site‐years, indicating that the hybrids, on average, responded similarly to starter fertilizer. Starter fertilizer increased early‐ season growth significantly in four of eight site‐years and grain yield in seven of nine site‐years. Average grain yield increases ranged from 4 bu/acre at the NW2 site in 1993 to 18 bu/acre at the SE site in 1995. Yield increases were not significant either year at the NW1 site. Increases in dry matter yield ranged from 18.7% at the SW site to 97.8% at the SE site in 1994. Starter fertilizer affected tissue K concentration to a much larger degree than it did N and P concentrations especially at the SE site. The results suggest that starter fertilizer will likely benefit no‐tillage corn for most hybrids in the northern corn belt even on soils with adequate P and K. Research Question No‐tillage systems have become attractive options for many corn producers because of potential on‐farm energy savings and the advantages of soil and water conservation. Residue cover on no‐tillage systems can result in cooler and wetter soils especially at time of planting. Cool soil temperatures can reduce early‐season growth, nutrient uptake, and yield of crops. However, starter fertilizers placed within the rooting zone of seedlings have been shown to improve early‐season corn growth and development due to better availability of the nutrients. Responses to starter fertilizers can vary among corn hybrids since they may differ in rooting characteristics, uptake and utilization of nutrients. The objective of this experiment was to evaluate the response of different corn hybrids to starter fertilizer in no‐tillage systems. Literature Summary Nitrogen and P are considered to be the essential ingredients in starter fertilizers. Some recent studies that have evaluated corn and grain sorghum response to N‐P starter fertilizers in no‐tillage environments, suggest hybrids res...

Information on the effectiveness of N fertilizer applied through sprinkler irrigation systems for springsown wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) is limited. Objectives were to determine grain yield and quality responses and N‐use efficiency when N fertilizer was applied at irrigation to wheat and barley grown on a fine‐silty, mixed Typic Haploboroll. Nitrogen fertilizer was applied to sprinkler irrigated ‘Newana’ hard red spring wheat and ‘Shabet’ malting barley at seeding or split between seeding and heading, flowering, or watery kernel growth stages. Treatments included N rates of 0, 50, 100, and 150 kg N/ha at seediig, 75 kg N/ha at seeding plus 25 kg N/ha at heading or flowering, and 50 kg N/ha at seeding plus 50 kg N/ha at heading or 25 kg N/ha at heading and 25 kg N/ha at flowering. Additionally, 25, 50, and 25 kg N/ha were applied to barley at seeding, heading, and flowering, respectively; and 100 and 25 kg N/ha were applied to wheat at seeding and watery kernel stage, respectively. Nitrogen at seeding was broadcast as NH4No3‐, Subsequent N applications were broadcast as NH4NO3, several, hours prior to an irrigation to simulate application through the sprinkler system. Wheat plots contained subplots fertilized with 15NH415NO3 containing 1.31 atom percent 15N to determine the fate and utilization efficiency of applied N. Grain yield increased from 1,100 to 4,850 and from 1,240 to 4,570 kg/ha for wheat and barley, respectively, as N rates were increased from 0 to 150 kg N/ha at seeding. When 100 kg N/ha was split between seeding and at irrigation, wheat yields decreased from 3,890 to 3,540 and 2,975 kg/ha as the amount of N applied at seeding was decreased from 100 to 75 and 50 kg N/ha, respectively. Barley yields averaged 4,130 kg/ha for treatments totaling 100 kg N/ha and were generally not affected by shifting N applications from seeding to at irrigation. Differential response to split applications of N was related to differences in number of spikes per unit area at harvest. The number of spikes/m2 decreased for wheat and increased for barley as the proportion of the N fertilizer applied at seeding decreased. Nitrogen fertilizer recovery in the straw and grain of wheat plants at harvest was 52.5 and 50.8% where 100 kg N/ha was applied at seeding or split between seediig and at irrigation, respectively. Percentage recovery of N fertilizer was lower in straw and higher in grain when N was applied at imgation as compared to seeding time application. Failure to obtain positive grain yield responses or increases in overall N fertilizer efficiency indicate no advantage to splitting N fertilizer applications between seeding and Irrigation for spring seeded wheat and barley on deep, medium‐fine textured soils

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