Effect of nitrogen supply by soil depth on sugarbeet production and quality

Nitrogen (N) supply is important in sugarbeet production to optimize yield and quality. Determining the effect of N supply by soil depth on sugarbeet production in the Northwest U.S. is important to continue fine-tuning management practices while minimizing negative environmental impacts. To accomplish this objective, a greenhouse column study was conducted by Amalgamated Sugar Company and USDA-ARS Northwest Irrigation and Soils Research Laboratory. The study was conducted using thirty, one meter by 0.3 meter columns filled with 0.9 meters of soil. The treatments consisted of adding N fertilizer at a rate of 132 kg N/ha to three 0.3 meter soil depths (depth 1 = 0-0.3 meters, depth 2 = 0.3-0.6 meters, and depth 3 = 0.6-0.9 meters). Each treatment was replicated six times in a randomized block design. Although all treatments (except the control) had a total N supply of 222 kg N/ha in the entire 0.9 meter soil depth, the distribution of the N in the soil profile affected the measured factors. Sugarbeet tuber mass, tuber sucrose mass, leaf (includes stems) mass, tuber N mass, leaf N mass were higher for treatments where N fertilizer was added to depths 1 and 2 compared to when N fertilizer was added to depth 3. Data indicates that sugarbeets were not able to utilize N from depth 3 as efficiently as from depth 1 and depth 2. The N use efficiency measurements (N recovery efficiency, N removal efficiency, and fertilizer N uptake efficiency) were greatest when 132 kg fertilizer N/ha was supplied in depths 1 and 2 compared to when some or all the 132 kg fertilizer N/ha supply was in depth 3. There were no treatment effects on sugarbeet quality factors. The sugarbeet plants did not utilize N in depth 3 as effectively as depths 1 and 2, and N levels in depth 3 did not negatively affect quality. The findings of this study highlight the need to question the value of a depth 3 soil sample for determining N fertilizer requirements. The cost/benefit evaluation of taking a soil sample to include depth 3 (0.6 to 0.9 meters) needs to be further evaluated in the field

Evaluation of strip-tillage and fertilizer placement in Southern Idaho corn production

Strip tillage (ST) and associated nutrient placement can potentially help producers reduce fuel and machinery costs, increase yield, and reduce soil erosion compared to chisel tillage (CT). This study was initiated to evaluate corn production (Zea mays L.) under ST and CT, and various nitrogen (N) and phosphorus (P) fertilizer placements. The effects of tillage practice and N and P placement on grain and biomass yield of field corn was assessed on two sites at the USDA ARS Northwest Irrigation & Soils Research Laboratory at Kimberly, ID with different levels of soil fertility and productivity. Two sites were selected in a furrow irrigated field that had been previously cropped to alfalfa. Site A was located in the top half of the field and Site B was located in the bottom half of the field. Site A had lower levels of soil organic C (OC) and soil test P and K compared to Site B. The treatments were 1) ST with deep placement of N and broadcast P; 2) ST with 2 by 2 placement of N and broadcast P; 3) ST with deep placement of N and P; 4) CT with 2 by 2 placement of N and broadcast P; and 5) CT with broadcast N and P. The grain yields at Site A were greater for ST compared to CT. The deep band placement of N and P with ST had a yield (175 bu acre-1) advantage of 23 and 16 bu acre-1 over both CT treatments, respectively and increased yields to levels similar to the average of Site B (178 bu acre-1). No differences in grain yield occurred at Site B for all treatments. There were no differences in biomass yield of corn at the VT (tassel) growth stage and grain harvest time at both sites. The average total dry matter biomass at grain harvest time was 9.1 and 10.4 tons acre-1 averaged over all treatments, respectively. Data from year one of this study indicates that ST and deep band placement of N and P increased corn grain yield over CT and conventional fertilizer placement methods in highly eroded low fertile soils. Irrespective of the potential yield increases there may be an economic advantage associated less fuel due to less tillage passages with ST compared to CT. Because the data presented in this paper is from one year, caution should be exercised in extrapolating these results from year to year due to the variability in crop production associated with time-specific factors. This study will be carried out over a least one to two more years before final conclusions and recommendations are issued

Effects of manure history and nitrogen fertilizer rate on sugar beet production in the northwest U.S.

Past manure applications effects on sugarbeet production needs to be assessed in the areas where manure applications to crop land are common. A study was conducted in Kimberly, Idaho in 2014 and 2016 to assess the effects of manure application history and N rates on sugarbeet production on a Portneuf silt loam (coarse-silty mixed mesic Durixerollic Calciorthid) soil. From 2004 to 2009, manure was applied to plots every two years (M1, total application = 60 tons per acre), every year (M2 total application = 106 tons per acre), or no manure (F, commercial fertilizer only). In spring 2014, the manure main plots were split in half with one half receiving a commercial fertilizer N rate treatment superimposed on the main plots in 2014 and the other half receiving the superimposed N rate treatments in 2016. In 2014 and 2016, the commercial fertilizer N rates were 0, 30, 56, 77, 100, 141, 180, and 202 pounds per acre. The study design was a randomized block split-plot with manure history as the main plot and N rate as the subplot. During both years of the study, N rate did not affect sugarbeet yields, but M1 and M2 treatments had higher sugarbeet root yields compared to the F treatment. Averaged across all N rates, root yields from both manured treatments were 12% and 36% greater than the F treatment in 2014 and 2016, respectively, although sugar yield was only significantly greater in 2016. Manure applications will impact sugarbeet production for several years after manure applications have ceased

Effects of sugarbeet processing precipitated calcium carbonate on crop production and soil properties

Precipitated calcium carbonate (PCC) lime is a byproduct of sucrose extraction from sugar beet processing factories in Idaho. Each year 351,000 Mg PCC is produced and stockpiled at sugarbeet factories in Idaho. There are currently no viable disposal strategies for the PCC and these stockpiles continue to grow in size each year. The simplest solution would be to apply this PCC directly to agricultural fields each year, however the effects of PCC on high pH soils and southern Idaho crop rotations are not well understood. A study was conducted at the USDA-ARS laboratory in Kimberly, Idaho to determine the effects of PCC application to an alkaline silt loam soil on sugar beet, dry bean and barley production and soil properties. Three PCC treatments (rate and timing) and an untreated control were compared. The PCC had no effects on crop production factors and most soil properties. The only significant effect of PCC treatments was an increase in soil phosphorus (P) concentrations compared to the control. The PCC can serve as a P fertilizer. For all crops in this study, PCC was applied at rates that resulted in applied P levels that were 1.6 to 5.3 times greater than even the highest published recommended P rates. Compared to the control, bicarbonate soil P concentrations increased by 25% and 73% for the final PCC application amounts of 26.9 Mg per ha (6.7A treatment) and 89.7 Mg per ha (6.7A and 89.7T treatments), respectively. The PCC used in this study can safely be applied (at rates up to 87.9 Mg per ha) to heavier textured alkaline soils in the local growing area. Disposing of PCC in this way represents a viable strategy for reducing PCC stockpiles

Evaluation of Nitrogen and Phosphorus Fertilizer Placement With Strip Tillage for Irrigated Pacific Northwest Corn Production

Nutrient placement options with strip tillage (ST) can potentially improve plant nutrient utilization and increase crop yield compared to conventional fertilizer placement practices under conventional tillage (CT). The effects of tillage practice and nitrogen (N) and phosphorus (P) placement on grain yield, biomass yield (whole plant, grain + cobs + stover), and N and P uptake of field corn (Zea mays L.) were assessed on four sites during 2007 and 2009 at the USDA-ARS Northwest Irrigation & Soils Research Laboratory at Kimberly, ID. During each year, two locations (eroded and not eroded from furrow irrigation) were utilized as study locations. Band placement of fertilizer with ST increased corn grain yield by 12.5 % (11 bu/acre) and 25.9% (26 bu/acre) on the eroded locations compared to broadcast N and P and 5cm×5cm N under CT in 2007 and 2009, respectively. These increased yields also resulted in better utilization of N and P by the plant. Reduced tillage costs of ST with associated band placement of N and P could increase the economic productivity of many acres of land in the Pacific Northwest

Nitrogen management in northwest U.S. sugarbeet production

Nitrogen (N) management is important in sugar beet production. This study was conducted to continue to fine-tune N management in the Northwest U.S. sugarbeet growing area. In 2018 and 2019, field studies were conducted at 6 locations by agronomists from The Amalgamated Sugar Company and scientists at the USDA-ARS Northwest Irrigation and Soils Research Laboratory in Kimberly, Idaho. The purpose was to evaluate the effect of N supply (fertilizer N + soil available N) on sugarbeet production. Five of the studies had a significant relationship between N supply and sucrose or root yield. The N supply required to maximize sucrose yields in the 5 responsive sites ranged from 145 to 258 kg N per ha. Data from our study supports past research showing that a Static Range N Management (SRNM) approach is valid as an alternative to a Yield Goal N Management approach which often leads to an over-supply of N. The average N supply required to maximize yields in our study was only 1 kg N per ha greater than that identified in our 2005-2011 study conducted in the same area (203 kg N per ha vs 202 kg N per ha). However, although optimal N supply was similar, the average maximum yield in this study was 22.2 percent greater than in the 2005 to 2011 studies. We suggest that sugarbeet growers determine N supply from a representative 0 to 0.9 m soil samples and employ a SRNM approach to N management. Continued research over time may be required to further fine tune the SRNM N range

Nitrogen Mineralization Response to Tillage Practices on Low and High Nitrogen Soils

Decomposition rates directly affect carbon and nitrogen ratios, which can affect nitrogen mineralization rates. The objective of this research is to determine the effect of tillage method and nitrogen rate on nitrogen available to sugar beets planted after a cereal crop. This two-year field study conducted in Kimberly, Idaho, consisted of three tillage methods (moldboard plow, chisel plow, and strip tillage), two tillage timings (fall and spring), and four fertilizer N rates plus a control. Soils from each plot were sampled shortly after nitrogen fertilization and incubated at average seasonal temperatures for Kimberly, Idaho to monitor nitrogen mineralization patterns. In 2008, we found that at N fertilizer rates of 0, 50, and 100 lbs N per acre, intensive tillage (moldboard plow and chisel plow) in the spring had the greatest potential for decreasing plant available nitrogen and increasing soil carbon, while intensive tillage in the fall slightly increased plant available nitrogen. No tillage method or tillage timing effects were detected in 2009, likely due to unexpectedly high residual nitrogen concentrations in the soil. It appears that tillage method and timing are more likely to impact nitrogen mineralization in growth limiting (low N) environments

Evaluation of Nitrogen and Phosphorus Fertilizer Placement With Strip Tillage for Irrigated Pacific Northwest Corn Production

Nutrient placement options with strip tillage (ST) can potentially improve plant nutrient utilization and increase crop yield compared to conventional fertilizer placement practices under conventional tillage (CT). The effects of tillage practice and nitrogen (N) and phosphorus (P) placement on grain yield, biomass yield (whole plant, sum of grain, cobs, and stover), and N and P uptake of field corn (Zea mays L.) were assessed on four sites during 2007 and 2009 at the USDA-ARS Northwest Irrigation & Soils Research Laboratory at Kimberly, ID. During each year, two locations (eroded and not eroded from furrow irrigation) were utilized as study locations. Band placement of fertilizer with ST increased corn grain yield by 12.5 percent (689 kg per ha) and 25.9 percent (1,626 kg per ha) on the eroded locations compared to broadcast N and P and 5cm by 5cm N under CT in 2007 and 2009, respectively. These increased yields also resulted in better utilization of N and P by the plant. Reduced tillage costs of ST with associated band placement of N and P could increase the economic productivity of many acres of land in the Pacific Northwest

Clinoptilolite Zeolite Influence on Inorganic Nitrogen in Silt Loam and Sandy Agricultural Soils

Development of best management practices can help improve inorganic nitrogen (N) availability to plants and reduce nitrate-nitrogen (NO3-N) leaching in soils. This study was conducted to determine the influence of the zeolite mineral Clinoptilolite (CL) additions on NO3-N and ammonium-nitrogen (NH4-N) in two common Pacific Northwest soils. The effects of CL application rate (up to 26.9 Mg ha-1) either band applied or mixed with a set rate of nitrogen (N) fertilizer on masses of NO3-N and NH4-N in leachate and soil was investigated in a column study using a Portneuf silt loam (coarse-silty mixed mesic Durixerollic Caliciorthid) and a Wolverine sand (Mixed, frigid Xeric Torripsamment). All treatments for each soil received a uniform application of N from urea fertilizer, with fertilizer banded or mixed with CL. In the Portneuf soil, band application of CL and N contained 109% more total inorganic N (NO3-N + NH4-N) in the soil/leachate system compared to mixing. In both soils, CL application rate influenced the quantity of NO3-N and NH4-N in the leachate and soil. Application of CL at rates of 6.7 to 13.4 Mg ha-1 resulted in the conservation of inorganic N in the soils. Band applying CL and N appears to conserve available inorganic N in the soil compared to mixing CL and N possibly due to decreased rates of microbial immobilization, nitrification and denitrification

Phosphorus mobility in soil columns treated with dairy manures and commercial fertilizer

The concentration of animal production in some areas of the United States has led to concern about the environmental fate of manure-derived phosphorus (P) in soils. A column study was conducted to quantify P leaching in a calcareous soil treated with monoammonium phosphate (MAP), two solid dairy manures (D1S and D2S), and two liquid dairy manures (D1L and D2L). A control with no P application was also included. Treatments were applied at 166 kg P ha-1 to columns packed with 20 cm of a Warden fine sandy loam (coarse-loamy, mixed superactive, mesic Xeric Haplocalcids) in a completely randomized design with four replications and housed in a climate-controlled growth chamber. Simulated irrigation water was added to the columns at a rate of 47.4 mm (450 mL) during 13 events during a 9-week period, with leachate collected, volume recorded, and concentrations of total organic carbon (TOC) and total P (TP) determined for each event. At the end of the leaching events, each soil column was divided into eight 2.5-cm segments. Then, soil was air-dried, ground, and analyzed for TP, total carbon, calcium (Ca), iron, and manganese, and water-soluble P. The masses of TP and TOC in leachate were in the order D1L=D2L > MAP=D1S=D2S=Control. There was a positive linear relationship between the cumulative mass of TOC and cumulative mass of TP lost in leachate over all manure treatments (r2=0.98). The masses of TP and water-soluble P for treatments in the entire soil columns were in the order MAP > D1L=D2L > D1S=D2S=Control. Masses of P and C in leachate and soil show that P mobility in soil was in the order liquid dairy manures > MAP > solid dairy manures. At the end of the study, the total C was greater in the surface 2.5 cm of the soil columns for the solid manure treatments compared with the other treatments/depth combinations. The greater leaching of P in the liquid manure treatments compared with the solid manure treatments may be caused by a combination of factors including microbial activity, organically complexed metals, coating of P adsorption sites on clay particles by organic C compounds, and P-Ca and P-aluminum reactions