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Sanyal, D
Bundy, L.G
Blanchard, P.E
Russelle, M.P
Specht, J
Wilson , M
Rutan, J
Gutknecht, J
Schmitt, M.A
Beyrer, T.A
Pradhan, G
Lindsey, A.
Grassini, P
Pohl, D.J
Bourns, M.A
Scharf, P.C
Goos, R.J
Pruden, T
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Authors
Beyrer, T.A
Sawyer, A
Rosen, C
Lamb, J
Sheaffer, C
Sadowsky, M
Gutknecht, J
Walker, Z.T
Yost, M.A
Coulter, J.A
Russelle, M.P
Yost, M.A
Russelle, M.P
Coulter, J.A
Schmitt, M.A
Sheaffer, C.C
Randall, G.W
Goos, R.J
Goos, R.J
Goos, R.J
Johnson, B.E
Goos, R.J
Bundy, L.G
Vitosh, M.L
Silva, G
Pruden, T
Ehrhardt, P.D
Bundy, L.G
Kitchen, N.R
Blanchard, P.E
Hughes, D.F
Goos, R.J
Feuchtenbeiner, J
Johnson, B.E
Goos, R.J
Mostafa, S.M
Johnson, B.E
Schmitt, M.A
Schmidt, J.P
Randall, G.W
Pohl, D.J
Mengel, D.B
Bundy, L.G
Bundy, L.G
Scharf, P.C
Bundy, L.G
Davis, J.G
Scharf, P.C
Kitchen, N.R
Walters, D.T
Dobermann, A
Cassman, K.G
Drijber, R
Lindquist, J
Specht, J
Yang, H
Studnicka, J.S
Bundy, L.G
Hubbard, V.C
Scharf, P.C
Osterhaus, J.T
Bundy, L.G
Good, L.W
Bundy, L.G
Bundy, L.G
Grassini, P
Sanyal, D
Wolthuizen, J
Karki, D
Clark, J
Bly, A
Sanyal, D
Rahhal, A
Bielenberg, H
Clark, J
Wolthuizen, J
Bly, A
Sanyal, D
Rahhal, A
Bielenberg, H
Wolthuizen, J
Clark, J
Bly, A
Clark, J.D
Bly, A
Karki, D
Sanyal, D
Wolthuizen, J
Kovacs, P
Teboh, J.M
Yuja, S
Schatz, B.G
Pradhan, G
Pfarr, C
Wilson , M
Steinke, K
Rutan, J
Rahhal, A
Sanyal, D
Wolthuizen, J
Bielenberg, H
Clark, J
Bly, A
Bielenberg, H
Clark, J
Bly, A
Sanyal, D
Wolthuizen, J
Rahhal, A
Novais, W
Sprunger, C.D
Lindsey, L.E
Khanal, S
Ortez, O
Mann, M
Lindsey, A.
Souza, E
Fernandez, F.G
Coulter, J
Wilson, M
Vetsch, J.A
Pagliari, P.H
Venterea, R.T
Kaiser, D.E
Fabrizzi, K.P
Bernau, D
Rosen, C.J
Mizuta, K
Miao, Y
Sharma, V
Wilson, M
Bourns, M.A
Nelson, N.O
Ruiz Diaz, D
Roa, G
Topics
Positive and negatives of cover crops
Correcting sulfur deficiencies
Soil N mineralization
N Management with Cover Crops
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Filter results41 paper(s) found.

1. Potassuim Chloride Fertilization and Common Root Rot of Barley

Common root rot (CRR, incited by Cochliobulus sativus) is one of the most widespread diseases of wheat and barley in the Great Plains and Prairie Provinces. Average yield losses, based on extensive surveys in the Prairie Provinces, average around 5% for wheat and 10% for barley, althoughinindividualfieldslossescanbemuchhigher. Potassium chloride fertilization has been effective in reducing CRR of barley in North Dakota, and I believe we are close to understanding why CRR is reduced by KC1 fertilization....

2. Ammonium Thiosulfate as a Urease Inhibitor- A suggested Mechanism

A great deal of interest, ard sca~ controversy, has been generaw by my observations (Goos, 1985a; Goos, 1985b; Fairlie and Goos, 1986) that ammonium thiosulfate (ATS, 12-0-0-265) can inhibit soil urease activity when mixed with fertilizers such as urea-ammonium nitrate (UAN) . Preliminary field research (Gascho and Burton, 1987; Fox and Piekielek, 1987; Lamond et al. 1986) has shown some increase in crop yields or N uptah by adding ATS to surface-applied UAN. However, the use of ATS as a urease inhibitor...

3. Combining Nitrification Inhibitor Technologies

Techniques exist for the partial control of nitrification, but few studies have determined the effectiveness of combining more than one technique. A series of experiments compared the nitrification rate of urea granules as influenced by granule size (0.01, 0.1, and 1.0 g/pellet) and dicyandiamide (DCD) addition (0, 1, 2, 5, and 10% of N) . A second series of experiments measured the interactive effects of DCD and ammonium thiosulfate (ATS) on nitrification of liquid fertilizers. Both experiments...

4. Nitrification of Banded Liquid Fertilizers

Field studies were conducted in 1990 at three sites to compare the relative effectiveness of ammonium thiosulfate (ATS, 12-0-0- 26s) , dicyandiamide (DCD) , and nitrapyrin (NP, ' N-Serve 24E' ) as nitrification inhibitors in combination with banded urea-ammonium nitrate (UAN). Applications were banded prior to planting spring wheat, and soil samples taken 2, 4, and 8 weeks after application. ATS, DCD, and NP inhibited nitrification at all three sites. ATS inhibited nitrification at the 4 week sampling,...

5. North Central Regional Nitrate Soil Testing Project

Although preplant soil nitrate (NO -N) tests have a long history of 3 successful use in semi-arid regions of the Western and Great Plains region of the United States (Hergert, 1987), soil NO -N testing in humid 3 regions is currently receiving substantial research attention. One of the most promising approaches to KO testing in the higher rainfall areas 3 of the Midwest and Eastern states is use of the pre-sidedress soil NO test (PSNT) (Magdoff et al., 1984). Research conducted in the humid 3 regions...

6. On-Farm Nitrogen Fertilizer Demonstrations

The Magdoff Pre-Sidedress Nitrate Test (PSNT) has been successful 1y used in the Northeast and humid parts of Midwest to improve N fertilizer recommendations. A modified version of the Magdoff PSNT was evaluated in 1989 and 1990 in Michigan. Fifty-three large scale on-farm corn N demonstrations were carried out. Two rates of N (a reduced rate and a high rate) were rep1 icated 3 to 6 times in each field. Forty-six sites showed no significant (p=.05) yield reduction due to the reduce N rate. Forty-nine...

7. Predicting Subsoil Nitrate Content from Surface Measurements

Preplant soil profile nitrate (NO,-N) tests are effective for I predicting corn (Zea mays L.) responsk to applied N. The difficulty of obtaining profile soil samples is one of the main obstacles to more extensive use of preplant tests. One approach to overcoming this barrier is to develop and use models to predict subsoil NO -N contents 3 from surface soil NO -N measurements. Data from 2295 routlne field 3 samples submitted to the University of Wisconsin Soil and Plant Analysis Laboratory from 1989...

8. Assessing the Source of Groundwater Nitrates- And You Thought Good Wine Took Time

Controversy continues with elevated groundwater nitrate concentrations being attributed to N fertilizer use. Current research defining best management practices in farming system K management seldom addresses the influence these practices have on groundwater. Why? The results of this Missouri research show that the influence of management on groundwater nitrates may last for decades. The study provides support for time requirements when assessing farming system impact on groundwater quality. ...

9. In Search of EAN of Spring Wheat

Many spring wheat varieties respond reliably to enhanced ammoniunl nutrition (EAN) in the greenhouse. Three field studies were established in 1992 to determine if similar responses could be obtained in the field. Butte 86 spring wheat was fertilized (100 Ib N/A) with calcium nitrate, urea, urea + DCD, forestry-grade (0.1 g) urea pellets and forestry-grade urea pellets + DCD. The goal was to provide wheat with a large range of a1nmonium:nitrate ratios and to determine the effect 011 wheat development...

10. Calcium Chloride Effects on Nitrogen Uptake by Small Grains

Applying calcium chloride (CaC12) with urea stimulated nitrogen uptake by small grains in six greenhouse studies. The effect was most dramatic for a sandy soil, moderate for a loam soil, and not observed for a clay soil. Allowing the urea to nitrify before plant uptake negated the CaC12 effect. In field studies, these effects were generally not observed, probably because the nitrification of the applied N was too rapid. However, this concept deserves further investigation, for example, when established...

11. Nutrient Credits for Manure--Differences Between Theory and Reality

It has been a mainstay recommendation for many years--take credit for the nutrients in the manure you spread on your fields. While it may seem that everyone is referring to an identical procedure, there are numerous strategies to crediting nutrients contained in manure. Although it appears to be simple, the complexities involved in crediting have resulted in few livestock and crop producers properly crediting nutrients from manure. Research and educational efforts have sharply increased in the past...

12. Soybean Nitrogen Contributions and Rotation Effects

Corn-soybean rotations are widely used in Midwestern grain production. These rotations usually produce higher corn yields and require less supplemental nitrogen (N) than corn grown following corn. The yield benefits are usually attributed to rotation effects, although the precise mechanisms responsible for the yield enhancement are often not well defined. Nitrogen contributions from soybean in rotations are also not well understood because nitrogen budgets for soybean show that soybean harvested...

13. Nitrogen Recommendations and Optimum Nitrogen Rates- How Do They Compare

The goals of University N recommendations for corn are to suggest adequate amounts of N to maximize economic return to the grower and simultaneously avoid excess N additions that can contribute to water quality problems. With increasing concerns about the contributions of aoricultural N to groundwater nitrate and to hypoxia in the Gulf of 3 Mexico. the appropnateness of N recomn~endations and their research basis are increasingly questioned. In addition, University N recommendations are often being...

14. Soybean Response to Nitrogen Applications

Soybean yield increases due to N fertilizer have been reported recently, particularly for N applications during the reproductive stages. It is also known that nitrate inhibits nodulat ion and nodule activity and could potentially reduce yield. Our objective was to evaluate the effect of N fertilizer on soybean yield. Forty-six experiments were conducted with N fertilizer applied at times ranging fiom planting to late reproductive stages. Some experiments had significant positive or negative responses...

15. Long-Term Nitrogen Fertilization Effects on Corn Yields and Soil Properties

A long-term experiment (1 958-2002) provides information about the sustainability of long-term nitrogen (N) fertilizer use and continuous corn production in the northern Corn Belt. The experiment includes three N rates (none, medium, and high) applied annually in a randomized complete block design with four replications. Nitrogen rates in the medium and high categories increased over time and are currently 125 and 250 lb Nlacre. Lime treatments were imposed on the long-term N rates in 1985 using...

16. Site-Specific Nitrogen Management for Reducing Soil Residual Nitrate

Site-specific N management has potential for increasing the efficiency of N fertilizer use, and thereby reducing environmental impact. Field studies were conducted in 2000 and 2001 to evaluate the potential for site-specific N management to reduce residual soil nitrate in Missouri cornfields. Field-size side-by-side fertilizer N treatment strips were applied in cooperating farmers' fields. The site-specific crop N requirement (optimal N rate) was determined for sub- blocks that contained a full...

17. Changes in Nitrogen use Efficiency and Soil Quality After Five Years of Managing for High Yield Corn and Soybean

Average corn gain yields in the USA have increased linearly at a rate of 1.7 bulacre over the past 35 years with a national yield average of 130 bdacre. Corn yield contest winners and simulation models, ho ~ever, indicate there is -100 bda in exploitable corn yield gap. Six years (1999-2004) of plant development, grain yield and nutrient uptake \yere compared in intensive irrigated maize systems representing (a) recommended best management practices for a yield goal of 200 bdacre (Ml) and (b) intensive...

18. Measuring Water-Extractable Phosphorus in Manures to Predict Phosphorus Concentrations in Runoff

Water-extractable phosphorus (WEP) in manures can influence the risk of P losses in runoff when manures are land applied. There is some uncertainty about how WEP in manures should be determined. Specifically, are WEP measurements affected by manure sample handling before analysis, and what manure extraction procedures are most appropriate for predicting potential P runoff losses after manure application? We evaluated several manure handling and extraction variables in determinations of WEP in manures...

19. Aerial Photos Can Predict Corn Yield Loss Due to N Deficiency

Fields that experience wet weather after N fertilizer is applied may lose N and consequently lose yield. Replacing N may be difficult or expensive after corn is too tall for tractor clearance. A tool to assess the degree of potential yield loss would help corn producers decide how much expense is justified in making late N applications. ...

20. Determining Economic Optimum Nitrogen Rates with the Illinois Soil Nitrogen Test and Soil Organic Nitrogen Fractions

Development of a diagnostic test to estimate soil N supplying capability is a continuing research need. The Illinois soil nitrogen test (ISNT) has been proposed as a method for adjusting corn (Zea Mays L.) N recommendations for to account for soil organic N contributions. We evaluated the ISNT as a tool for predicting corn N response in Wisconsin by comparing ISNT values and corn N response data from-81 experiments conducted between 1984 and 2004 with a range of crop rotations, management histories,...

21. Validating the Wisconsin P Index with Measured Runoff P Losses From Agricultural Fields

Phosphorus (P) indices have been developed by most states in the USA for use as planning tools to assess the risk of P loss and identify appropriate management alternatives to control these losses where needed. Little information is available on the relationshp between P index values and actual P runoff losses in the field. We compared annual P losses in runoff measured at 2 1 field or sub-watershed locations with Wisconsin P index values calculated for the same areas. The research sites included...

22. Nitrogen Mineralization Estimates for N Rate Suggestions

To improve the accuracy of N rate recommendations for corn, reliable estimates of soil N supplying capability are needed. The important influence of soil N supplying capability on estimating corn N needs is illustrated by a recent compilation of data on corn yield response to N fertilization fiom over 300 experiments in Illinois, Iowa, Minnesota, and Wisconsin showing that 50 to 70% of the observed corn yield was produced with N supplied by the soil alone (Sawyer et al., 2006). The soil available...

23. On-Farm Assessment of Nitrogen Use and Management in Irrigated Corn Production in Nebraska

High-yield irrigated crops have large nitrogen (N) requirements. For example, N uptake of a corn crop that yields 207 bu ac -1 (~13 t/ha) is about 180 lb N ac-1 (200 kg N ha-1). The amount of N that is not provided by indigenous sources (mineralization of previous crop residue and soil organic matter) needs to be supplied by crop producers through N fertilizer. High-yield irrigated corn accounts for 74% of total annual corn production of 1260 million bushels in Nebraska. With approximately 70,000...

24. Improving Corn Yield Potential with Banded Phosphorus Fertilizer

High fertilizer costs and concerns about water quality issues have caused many Midwest corn producers to take a greater interest in improving the efficiency of phosphorus (P) fertilizer applications. The objective of this research was to determine the effects of P source, rate and placement on P use efficiency in high-yield corn production systems. The experiment was conducted in 2013 at two locations in Illinois. Two P fertilizer sources (mono-ammonium phosphate (MAP, 11-52-0) or an enhanced MAP...

25. Switchgrass Rhizobacterial Community Structure as a Function of Cultivar and Nitrogen Fertility at Two Sites in Minnesota

Biofuel production using native perennial grasses such as switchgrass (Panicum virgatum) has potential to reduce U.S. dependence on foreign oil and curtail greenhouse gas emissions. Switchgrass can also provide significant ecosystem services, such as nutrient loss reduction and carbon sequestration. Best management practices (BMPs) for switchgrass fertility are being established on a regional basis, yet little work has been done to examine the intersection of soil fertility with soil biology in switchgrass-for-biofuel...

26. Accuracy of Credits and Soil Indicies for Predicting Nitrogen Response in Corn Following Alfalfa

Corn is the most frequent first- and second-year crop following alfalfa in the upper midwestern United States. In the majority of reported cases, there is little need for additional fertilizer N to optimize yield of first-year corn following alfalfa. For second-year corn following alfalfa, fertilizer N is needed in about one-half of cases and the economically optimum N rate (EONR) has varied greatly in responsive fields. The objective of this research was to use literature data to evaluate the accuracy...

27. Stand Age Affects Fertilizer Nitrogen Response in First-Year Corn Following Alfalfa

Through a symbiotic relationship with soil bacteria, alfalfa can acquire nitrogen (N) from the atmosphere, use the N for its own growth, and contribute large amounts of N to subsequent crops. To estimate this N contribution, most land-grant universities use book-value N credits based on alfalfa stand density at termination. However, a recent literature analysis indicated that alfalfa stand density is not a reliable predictor of grain yield response to fertilizer N in first-year corn. That analysis...

28. Intensive Nitrogen Management of Soft Red Winter Wheat

The current system of making nitrogen recommendations for wheat in the Eastern cornbelt assumes that nitrogen fertilizer required is a simple function of yield potential. The higher the yield potential, the more N fertilizer needed. The problem with this assumption is that factors such as soil type and ability of a site to release N through mineralization, climate, variety. disease pressure and managetnent practices all affect nitrogen use efficiency, and are not considered in making nitrogen recommendations....

29. Cover Crops Influence Soil Health and Nutrient Cycling in a Multi-Location Study in South Dakota

Soil without living roots potentially loses mobile nutrients and retains excess water. Unprotected soil degradation and erosion enable the loss of carbon and nutrient rich top soil. Cover crops provide armor for the soil protecting from carbon and nutrient loss. Cover crop blends may influence soil health parameters and nutrient cycling. This multi-locational study depicts the influence of cover crop species blends with varying grass and broadleaf concentrations on established soil-health indicators... D. Sanyal, J. Wolthuizen, D. Karki, J. Clark, A. Bly

30. Does cover crop composition improve soil health and enhance nutrient availability to cash crops?

Crop and livestock producers in South Dakota are showing greater interest in cover crops for the multidimensional benefits it can provide towards enhanced nutrient availability to the cash crops and livestock nutrition. Growers use different blends of grasses and broad leaves, mostly legumes and brassicas, as cover crops. We hypothesized that carbon and nitrogen ratio and fiber composition in those cover crop residues regulate the nutrient release, thus influence the processes regarding nutrient... D. Sanyal, A. Rahhal, H. Bielenberg, J. Clark, J. Wolthuizen, A. Bly

31. Do cover crops improve soil health and enhance nutrient availability to cash crops?

Bare soils are prone to erosion and lose soluble nutrients. Cover crops provide protection to the soil against erosion and nutrient loss. We hypothesized that the cover crops should uptake available nutrients from the soils in the fall when there is no cash crop, assimilate the nutrients in their tissues, and in the following spring, should release the nutrients back to the soil during the next cash crop growing season. In our study, we are quantifying the nutrients taken up by the cover crops... D. Sanyal, A. Rahhal, H. Bielenberg, J. Wolthuizen, J. Clark, A. Bly

32. No-till and Cover Crops Influence Soil Health and Nitrogen Rate and Timing Recommendations: Early Results

The idea of improving soil health has become increasingly more talked about by researchers, agronomists, and farmers in the past five years. Management practices such as no- or reduced-tillage and planting cover crops are recommended to improve soil health because of their potential to improve organic matter and soil structure leading to a greater capacity to hold water and nutrients needed for plant growth. Research in South Dakota has been occurring these past two years to determine the influence... J.D. Clark, A. Bly, D. Karki, D. Sanyal, J. Wolthuizen, P. Kovacs

33. Impact of sulfur and its interaction with N rates on wheat and barley in North Dakota and Western Minnesota

Effects of S, N, and their interactions were assessed on grain yields and protein of spring wheat and barley, across eight site years in Western Minnesota (MN), and ten site years (hereafter, sites) in North Dakota (ND) from 2015 to 2019. The studies were to determine if S improves yields and protein in wheat, and if the effects were dependent on N rates. Treatments included all combinations of five N rates of N (0, 60, 120, 180, and 240 lbs/ac) and three rates of S (0, 10, 20 lbs/ac) in MN. In... J.M. Teboh, S. Yuja, B.G. Schatz, G. Pradhan

34. Sidedressed swine manure slurry via dragline hose produces comparable corn grain yields as commercial fertilizers

Spring in the upper Midwest can be short and often wet, providing challenges for producers to apply manure and plant crops in a timely manner to maximize yield. As a result, producers apply a significant amount of their manure in the fall after the crop is harvested. Fall applied manure has adequate time to mineralize and leave the root zone before next season’s crop can utilize the nutrients the following summer. These nutrients can end up in rivers and other freshwater bodies, decreasing... C. Pfarr, M. Wilson

35. Corn Nitrogen Management Following Cover Crops and the Microbial Response

Cover crops (CCs) may provide tools for fertilizer management and opportunities to influence soil biological communities. However, corn (Zea mays L.) growth and microbial response remain unclear when corn nitrogen (N) management strategies are practiced in combination with specific CCs. Field studies were conducted in 2015 and 2016 to evaluate the effects of no CC, Daikon radish [Raphanus sativus (L). var. The Buster], and Forage oat [Avena sativa (L.) var. Magnum]... K. Steinke, J. Rutan

36. Cover crops nutrients uptake did not cause yield loss in corn

Bare soils are susceptible to erosion and nutrient loss. Cover crops and residues provide physical protection against erosion and nutrient loss, and improve nutrient cycling as well as biodiversity. We hypothesized that cover crops store available nutrients from the soil in the fall and release them the next spring for the next cash crop, minimizing potential nutrients loss with no adverse effect on cash crop yield. A four site-year study throughout South Dakota was conducted to compare...

37. Can Cover Crops Help to Improve Soil Health While Having a Positive Effect on Corn Grain Yield?

Cover crops have recently gained attention in the U.S. Mid-west because of their potential to increase soil organic matter and improve overall soil health. There is some concern however, that cover crops may negatively impact corn grain yield. This study was conducted to determine the effects that different cover crop mixtures have on soil health measurements and corn grain yield at increasing nitrogen rates. Cover crops were planted in the fall as a dominantly grass mixture, dominantly...

38. Elucidating How N Management Practices and Excess Water Conditions Affect Corn N Uptake and Grain Yield

Flooding and waterlogging events have been more frequent in the Midwest region, causing corn yield penalty nitrogen losses through leaching and denitrification processes. Improving N fertilizer recommendations for areas prone to flood conditions is necessary to minimize N losses and optimize corn yield. This research aimed to determine how N application practices before and after waterlogging events impact corn growth and grain yield. A field experiment was initiated in 2021 in Custar, Ohio using... W. Novais, C.D. Sprunger, L.E. Lindsey, S. Khanal, O. Ortez, M. Mann, A. . Lindsey

39. A Minnesota-Wide Assessment of Critical Pre-Plant and in-Season Soil Nitrate for Adjusting Nitrogen Rate Guidelines

The pre-plant (PPNT) and pre-sidedress (PSNT) soil nitrate tests are often used as indicators of soil nitrogen (N) availability in Minnesota. The assessment of available soil nitrogen (N) provides corn (Zea mays L.) growers with key information on N credits to adjust their N fertilizer rates. However, current N management recommendations in Minnesota were based on research conducted 40-yr ago and did not specify differences between environments and management. Through a comprehensive... E. Souza, F.G. Fernandez, J. Coulter, M. Wilson, J.A. Vetsch, P.H. Pagliari, R.T. Venterea, D.E. Kaiser, K.P. Fabrizzi, D. Bernau, C.J. Rosen, K. Mizuta, Y. Miao, V. Sharma

40. In-season Application of Swine Manure to Corn

In agricultural areas with cool climates, application of livestock manure for crop production can be challenging. For example, spring in the upper Midwest can be short and is increasingly wet due to climate change, making it difficult to apply manure and plant crops in a timely manner. This results in a significant amount of manure applied in the fall after the cash crop is harvested. The nitrogen in fall-applied manure has ample time to mineralize and leave the root zone before next season’s... M. Wilson

41. Developing a Sustainable Sufficiency Paradigm

Sustainable conservation practices must align agronomic productivity and environmental protection goals to facilitate widespread and consistent adoption on-farm. Agricultural phosphorus (P) management is a critical control point for detrimental environmental consequences of P loss in surface runoff from agricultural fields. Reduced P fertilizer inputs are recognized as an effective and necessary control measure to limit P loss; however, current P fertilizer recommendation systems do not support... M.A. Bourns, N.O. Nelson, D. Ruiz diaz, G. Roa