HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by St. John, R. A. Articles by Taber, H. G. Search for Related Content PubMed Articles by St. John, R. A. Articles by Taber, H. G. Agricola Articles by St. John, R. A. Articles by Taber, H. G. Related Collections Turfgrass Management Turfgrass Soil Chemistry

TURFGRASS SCIENCE

Supplemental Calcium Applications to Creeping Bentgrass Established on Calcareous Sand

Dep. of Horticulture, Iowa State Univ., Ames, IA 50011

^* Corresponding author (rstjohn{at}iastate.edu)

	ABSTRACT

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Sand-based athletic fields and golf course greens may contain large amounts of CaCO₃. Calcium is frequently applied to these areas based on the belief that the Ca within the CaCO₃ is not readily available for plant use. Our objectives were to determine if Ca applied to creeping bentgrass grown on calcareous sand increases Ca uptake, affects the clipping yield or quality of the grass plant, or affects the availability of other nutrients. A 2-yr field trial was initiated on a calcareous sand-based green established with ‘Crenshaw’ creeping bentgrass {Agrostis palustris Huds. [= Agrostis stolonifera var. palustris (Huds.) Farw.]}. Treatments included gypsum (CaSO₄), CaCO₃, Ca nitrate [Ca(NO₃)₂·4H₂O], and liquid Ca chelate applied across five months at 4.5 g Ca m^-2 per month and an untreated control. Urea was added to balance the N found in the Ca(NO₃)₂ and Ca chelate treatments. Throughout the experiment, there were no differences in tissue Ca content, visual quality, or clipping yield in response to the Ca treatments. With the exception of the CaSO₄ treatment in 1999, application of Ca did not significantly affect the leaf concentrations of the other nutrients. During the first year, creeping bentgrass grown in plots receiving CaSO₄ contained 11% less tissue Mg than the creeping bentgrass in the control plots. Supplemental Ca applications to creeping bentgrass established on calcareous sand had no beneficial effects.

Abbreviations: BCSR, basic cation saturation ratio • CEC, cation exchange capacity • SLAN, sufficiency levels of available nutrients

	INTRODUCTION

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
TO INCREASE DRAINAGE and decrease problems with compaction, most golf course greens and athletic fields are constructed with the sandy root-zone mix recommended by the United States Golf Association (United States Golf Association Green Section Staff, 1993). Because of the inherent properties of sand, these root zone mixes have low cation exchange capacities (CECs), ranging from 1 to 6 cmol_c kg^-1 (Christians, 1990). With so few cation exchange sites available, applying the correct amount of fertilizer to provide adequate plant nutrition without causing oversaturation of the exchange sites and nutrient leaching is difficult. To further complicate the problem, the sand used for greens and athletic field construction in many areas of the United States is often calcareous. Calcareous sands are defined as having any amount of free carbonates, usually as combinations of CaCO₃ and/or MgCO₃. The free carbonates in these sands will often range from 1 to 40% by weight. The carbonates will buffer the pH at 8.2, but standard pH meters may measure it in a range from 7.3 to 8.5 (Christians, 1990). This very high pH can limit the availability of many other nutrients, such as Fe, Mn, and B.

In recent years, more and more turf managers have been applying supplemental Ca applications to turf areas established on sand. Usually, these applications are made with granular CaSO₄, CaCO₃, or liquid sprays of Ca chelate. One of the main reasons generally cited for applying supplemental Ca to grass established on calcareous sand is the belief that the CaCO₃ does release Ca quickly enough to be readily available for plant uptake. There is a lack of data supporting this idea, and further work is needed to determine the availability of the Ca in the CaCO₃ to plants.

A second reason for applying Ca to turfgrass is sometimes based on the basic cation saturation ratio (BCSR) theory of soil testing. According to the original theory by Bear and Toth (1948), optimal plant growth is achieved when Ca, Mg, K, and H occupy the exchange complex with the following ideal ratio of saturation percentages; 65% Ca, 10% Mg, 5% K, and 20% H. On the basis of these saturation percentages, one can develop the ideal cation equivalent ratios of Ca:Mg 6.5:1, Ca:K 13:1, Ca:H 3.25:1, and Mg:K 2:1 (Bear and Toth, 1948). This theory was later expanded so that the basic cations exist within the percentage saturation ranges of 65 to 85% Ca, 6 to 12% Mg, and 2 to 5% K, with H ions occupying the remaining exchange sites (Eckert, 1987). The alternative philosophy of soil test interpretation is called sufficiency levels of available nutrients (SLAN). The SLAN theory states that there are minimum levels of nutrients in the soil, below which the crop will respond favorably to fertilizer application (Eckert, 1987). The SLAN philosophy is based on much research with varying soil and crop types, which has led to the development of soil test interpretation guidelines for specific crops grown in specific geographical areas.

Research demonstrating turfgrass response to Ca and the interaction of Ca with calcareous sand systems is limited. Calcium deficiencies of ‘Merion’ Kentucky bluegrass (Poa pratensis L.), ‘Seaside’ creeping bentgrass, and ‘Pennlawn’ creeping red fescue (Festuca rubra L.) grown on acid-washed quartz sand have been described as starting with a reddish-brown discoloration along the margin of the leaf blade that moves inward to the midvein as the leaf ages, changing the leaf to a rosy red color (Love, 1963). Kentucky bluegrass, creeping bentgrass, and creeping red fescue became deficient in Ca when the leaf Ca concentration reached 500, 2700, and 1900 mg kg^-1, respectively (Love, 1963). St. John et al. (2001) concluded that Kentucky bluegrass and creeping bentgrass established on calcareous sand in the greenhouse are capable of obtaining their Ca requirements from calcareous sand, and no additional Ca is needed. Research conducted by Sartain (1993) found that maintaining a precise soil Ca:Mg ratio in ‘Tifway’ bermudagrass [Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt Davy] and ‘Pennant’ perennial ryegrass (Lolium perenne L.) was not important; rather, it was more important to maintain a minimum critical level. ‘Tiffgreen’ bermudagrass has been shown to tolerate soil extractable Ca:Mg ratios, ranging from 13:1 to 120:1 without a reduction in growth (Sartain, 1985).

In his review of soil test interpretations, Eckert (1987) stated that he did not know of any study that has shown that an exact "ideal ratio" exists. However, he goes on to state that the theory appears to be "reasonable in light of basic cation exchange phenomena and the effects that the degree of saturation of one cation may have on the availability of itself and other cations". The ratio of basic cations is only important when one cation becomes so excessive that it limits the availability of the others (McLean, 1977). Excess Ca fertilization could potentially shift the cation equilibrium and remove the other cations, such as Mg or K, from exchange sites, causing plant deficiencies of these elements. St. John et al. (2001) found that during 1 yr of a 2-yr greenhouse study, creeping bentgrass established on calcareous sand fertilized with Ca nitrate reduced leaf Mg concentration by 15%. Fertilization with either K or Mg has been shown to reduce the tissue Ca concentration of tall fescue (Festuca arundinacea Screb.) (West and Reynolds, 1984). Applications of either K or Mg to bermudagrass and perennial ryegrass reduced the levels of extractable soil Ca (Sartain, 1993). Miller (1999) also found that increasing the amount of K applied to bermudagrass established on both a sandy peat and a loamy sand decreased the soil-extractable amount and the tissue concentration of Ca and Mg. Excess Ca fertilization may also hinder the ability of the plant to absorb P, since excess Ca in the presence of CaCO₃ will precipitate with P and form insoluble Ca phosphates (Larsen, 1967). Westermann (1992) found that increasing lime concentrations reduced P uptake of sudangrass [Sorghum bicolor (L.) Moench] and potato (Solanum tuberosum L.).

The objectives of this study were to determine the effects of applying supplemental Ca to a calcareous sand-based creeping bentgrass green. Specifically, the objectives were to determine if additional Ca fertilization (i) increases the amount of Ca absorbed by creeping bentgrass, (ii) increases the clipping yield and/or quality of the bentgrass green, and (iii) affects the availability of other nutrients to the plant.

	MATERIALS AND METHODS

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
A 2-yr field study was conducted on a creeping bentgrass green at the Iowa State University Turfgrass Research Farm. Treatments including a control, CaSO₄, CaCO₃, Ca(NO₃)₂·4H₂O, and Nutri-Cal liquid Ca chelate (C.S.I. Chemical Corp., Bondurant, IA) (8% Ca, 6% N), were applied to a Crenshaw creeping bentgrass, sand-based green constructed without any organic or inorganic soil amendments. At the time this research began, the green was built and seeded in 1996. The calcareous sand in the green had a CaCO₃ content of 110 g kg^-1 and an organic matter content of 4.3 g kg^-1. The green was mowed daily at a height of 3.8 mm. The irrigation water contained 3 mg kg^-1 NO₃–N, 35 mg kg^-1 Ca, 22 mg kg^-1 Mg, 17 mg kg^-1 K, 1 mg kg^-1 P, 2.8 meq L^-1 alkalinity, and had a pH of 7.8.

Calcium was applied at a rate of 23 g Ca m^-2 yr^-1. That quantity was split into five equal monthly applications in June, July, August, September, and October. Since Ca nitrate and Ca chelate both contain N, 15.5 and 6%, respectively, urea [(NH₂)₂CO] was added to balance the level of applied N across all the treatments to the rate of 18.3 g N m^-2 yr^-1. Urea was added at a rate of 39.87 g m^-2 yr^-1 to the control, gypsum, and CaCO₃ treatments. Urea was added at a rate of 3.23 g m^-2 yr^-1 to the Ca chelate treatment to balance the N at a total of 39.87 g m^-2 yr^-1. The urea, Ca nitrate, and Ca chelate treatments were mixed with H₂O and sprayed at a pressure of 207 kPa using a CO₂–powered backpack sprayer calibrated to spray 123 mL H₂O m^-2. The gypsum and the CaCO₃ materials were granularly applied. After application, the treatments were watered-in with 1 cm of water. Regular mowing was halted for 2 d after treatment application. The granular products were pelletized powders; therefore, the pellets easily broke down and worked down into the canopy with irrigation water. During the course of this study, no other nutrients were applied to the research plots.

Clippings were taken immediately before the fourth and fifth treatments each year. The clippings were dried at 67°C for 6 d, weighed, and ground in a Wiley mill to pass through a 40 mesh screen. Total leaf N was determined by using a modified microKjeldahl (TKN, total Kjeldahl nitrogen) digestion procedure (Jones, 1991; Nelson and Sommers, 1980) in combination with a nitroprusside-salicylate assay (Wall et al., 1975) using flow injection analysis (Smith and Scott, 1990). After dry ashing at 490°C and digesting in aqua regia, leaf tissue nutrient concentrations were determined by using inductively coupled argon plasma emission techniques (Jones, 1977; Munter and Grande, 1981). Each year, immediately before the October treatment application, root and soil samples were taken at random from each plot. Three root samples 5 cm in diameter and 16 cm in depth were taken from each plot, washed, dried at 67°C for 6 d, and weighed. Twelve soil cores, 2 cm in diameter by 13 cm in length, were taken from each plot. The thatch layer was removed and discarded. The 12 cores from each plot were combined and analyzed by different methods. A private soil testing laboratory analyzed our soil samples using their standard procedures. The exchangeable cations were determined by the ammonium acetate (NH₄OAc) pH 7.0 extraction method (Thomas, 1982); the CEC was estimated by summing the exchangeable cations, and a set of basic cation saturation percentages and cation ratios were generated from this data. The soil samples from both years were analyzed using these procedures. Further analysis of the soil samples from the second year was performed in the Plant Nutrition Lab at Iowa State University. The exchangeable basic cations were determined on 0.5 M ammonium chloride (NH₄Cl) pH 7.0 extracts (Suarez, 1996). A second CEC determination was performed by Na saturating the soil with a 60% ethanol solution of 0.4 M sodium acetate (NaOAc) - 0.1 M sodium chloride (NaCl) and displacing the Na with 0.25 M magnesium nitrate [Mg(NO₃)²] (Rhoades, 1982).

The experimental design was a randomized complete block with three replications. The data were analyzed using the General Linear Models (GLM) procedures of the Statistical Analysis System software (SAS Institute, 1996).

	RESULTS

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Throughout both years of the study there were no differences in bentgrass color, quality, density, or uniformity among any of the treatments. There were no differences in root dry mass or dry clipping mass during either year (Tables 1 and 2).

On the basis of the sufficiency levels published by Mills and Jones (1996), the creeping bentgrass tissue concentrations of N, P, K, and Mg were low both years with the exception of Mg concentration in 2000 (Tables 1 and 2). However, based on golf course green survey ranges (Mills and Jones, 1996), leaf concentrations of N, P, K, and Mg were within the survey ranges, with the exception of P levels in 1999 (Tables 1 and 2).

Since there were no interacting effects between treatments and years for the NH₄OAc extractions, the soil test data from the 2 yr were combined for analysis. The concentration of extractable Ca in the soil did not increase in the plots where extra Ca was applied (Table 3). The extractable levels of Ca and Mg were within recommended soil test levels, with K being below the recommended level (Table 3). Applications of CaCO₃ and Ca(NO₃)₂ reduced the NH₄OAc extractable soil K levels by 19% (Table 3). Gypsum, Ca(NO₃)₂, and Ca chelate applied to the green reduced the NH₄OAc extractable soil Mg concentration by 16, 17, and 15%, respectively (Table 3). According to the NH₄OAc soil test, the magnesium saturation percentages were reduced in plots receiving CaSO₄, Ca(NO₃)₂, and Ca chelate by 13, 11, and 11%, respectively (Table 4). Basic cation saturation percentages and cation ratios are presented in Table 4. The sum of the exchangeable cations extracted with NH₄Cl resulted in a slightly higher CEC than the CEC measured by the NaOAc/NaCl procedure. Therefore, an estimated cation exchange capacity (ECEC) was used in the creation of the saturation percentages and ratios in the lower half of Table 4.

	DISCUSSION

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Since there were no increases in clipping yield, color, quality, or Ca content of the creeping bentgrass, adding Ca to creeping bentgrass established on calcareous sand was not beneficial in this study. Recent research on Kentucky bluegrass and creeping bentgrass established on calcareous sand has also demonstrated that calcareous sand used in those experiments provided the necessary Ca required by both grasses, and that extra Ca applications were not needed (St. John et al., 2001). Furthermore, research on vegetable crops grown in quartz sand culture has shown that Ca fertilization can increase leaf Ca concentrations without improving plant health, growth, and color (Spiers, 1993; Spiers and Braswell, 1994).

With the exception of the CaSO₄ treatment in 1999, the addition of Ca to the green did affect the bentgrass leaf nutrient concentrations. Sand has a very small CEC, limiting the number of cations it can hold at any one time. Therefore, the percentage of each ion on the exchange complex can easily change. Adding an excess of any cation to a sand-based system may cause a shift in the concentration of the other cations. This competition for exchange sites may have caused the reduction in leaf Mg concentration of the bentgrass that received CaSO₄ during the first year. This effect of CaSO₄ was not significant during the second year; however, there was a trend for lower leaf Mg concentrations in plots treated with CaSO₄. It is unclear why the reduction in tissue Mg concentration was not significant during the second year of the study. Also, there were reductions of NH₄OAc extractable soil Mg and K in many treatments during both years, but the same reductions were not present in the extraction performed at Iowa State University. The NH₄OAc method is not suitable for calcareous sands because it dissolves CaCO₃, and overestimates exchangeable Ca content. However, exchangeable Mg and K levels should be relatively unaffected by the NH₄OAc extraction. The same reductions were not significantly lower in the NH₄Cl extracts, perhaps because only one year's soil samples were analyzed. While reduction in leaf Mg concentration occurred only once in this study, with time the reduced saturation percentages and soil-exchangeable concentrations of Mg and K could eventually cause plant deficiencies. This reduction of one cation by another cation has been noted by other researchers (Eckert and McLean, 1981; West and Reynolds, 1984; Sartain, 1993; Spiers and Braswell, 1994; Miller, 1999; St. John et al., 2001). Many studies have concluded that maintaining a minimum critical level of Ca and Mg is more important than trying to target certain Ca:Mg ratios (Rossi et al., 1988; Sartain, 1985; Sartain, 1993; St. John et al., 2001). As long as Ca is the dominating cation, the exact balance of cations is not important (Eckert and McLean, 1981). Although it has been shown that excess Ca in the presence of CaCO₃ will precipitate with P (Larsen, 1967), there were no apparent Ca-P interactions in this experiment.

The nutrient concentrations found in the creeping bentgrass leaves were low when compared to sufficiency ranges listed by Mills and Jones (1996), but most of the nutrient concentrations fell within their survey ranges for creeping bentgrass greens. Mills and Jones (1996) state that the sufficiency ranges are derived from published deficiency and toxicity levels, whereas the survey ranges more closely match what the authors feel as actual sufficiency ranges.

During the course of the experiment, it was discovered that the private soil-testing laboratory was using the pH 7.0 NH₄OAc method of analysis. The NH₄OAc procedure is not recommended for calcareous soils (Rhoades, 1982; Sumner and Miller, 1996; Normandin et al., 1998). Therefore, a comparison analysis using a different set of procedures was performed on the second year's set of soil samples. The BCSRs are based on the total CEC of the soil and the concentration of exchangeable basic cations, which causes two problems when relating it to turfgrass grown on sand-based rootzones. First, high sand rootzones have a limited CEC, which increases the chance for errors when calculating cation percentages of such a small CEC. Second, many private soil-testing facilities use the ammonium acetate (pH 7.0) method for determining exchangeable cations and the summation of the basic cations method to estimate the CEC. These results are then combined to produce a set of saturation percentages and cation ratios. The NH₄OAc pH 7.0 method should not be used on calcareous soils because it will dissolve some CaCO₃, thus overestimating the actual amount of exchangeable Ca in the soil. When the exchangeable basic cations are summed together to estimate a CEC value, the CEC will be greatly overestimated. Therefore, basic cation saturation percentages made from these two possibly erroneous numbers would also be misleading. Moreover, cation ratios like Ca:Mg, made from the NH₄OAc method, would also be erroneous. The Ca:Mg ratios were more than two times higher in the analysis provided from the NH₄OAc method compared with the NH₄Cl method. Further, work needs to be done to determine how many private laboratories are using incorrect soil testing procedures for calcareous soils, and how that affects the interpretation of the fertilizer requirements for turfgrass systems.

On the basis of the NH₄Cl soil tests, the calcareous sand used in this experiment was within the proper Ca and K saturation percentages recommended by the BCSR theory of soil testing, but the Mg saturation percentages were above the recommended range. Moreover, the sand was also within the soil nutrient levels based on the SLAN theory. Further work would be required to determine if low CEC calcareous sands, with low Ca saturation ratios, would benefit from supplemental Ca applications.

This research revealed no increases in the Ca content of the creeping bentgrass, no changes in visual color or quality of the bentgrass, and there were some possibly detrimental interactions between added Ca and other nutrients. Therefore, there was no indication of a need to apply extra Ca to creeping bentgrass grown on calcareous sands used in this study.

	ACKNOWLEDGMENTS

 
We would like to thank the Iowa Turfgrass Institute and the Iowa Golf Course Superintendents Association for their support, and Diane Shogren from the Iowa State University Plant Nutrition Lab for her technical help.

	NOTES

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Journal Paper No. J-19600 of the Iowa Agriculture and Home Economics Experiment Station, Ames, IA. Project No.3601 and supported by Hatch Act and State of Iowa funds.

Received for publication November 14, 2001.

	REFERENCES

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 

• Bear, F.E., and S.J. Toth. 1948. Influence of calcium on availability of other soil cations. Soil Sci. 65:69–74.
• Christians, N.E. 1990. Dealing with calcareous soils. Golf Course Manage. 58(6):60–66.
• Eckert, D.J. 1987. Soil test interpretations: Basic cation saturation ratios and sufficiency levels. p. 53–64. In J.R. Brown (ed.) Soil testing: Sampling, correlation, calibration, and interpretation. SSSA Spec. Publ. 21. SSSA, Madison, WI.
• Eckert, D.J., and E.O. McLean. 1981. Basic cation saturation ratios as a basis for fertilizing and liming agronomic crops: I. Growth chamber studies. Agron. J. 73:795–799.[Abstract/Free Full Text]
• Jones, J.B., Jr. 1977. Elemental analysis of soil extracts and plant tissue ash by plasma emission spectroscopy. Commun. Soil Sci. Plant Anal. 8:345–365.
• Jones, J.B., Jr. 1991. Kjeldahl Method for nitrogen (N) determination. Micro-Macro Publ., Athens, GA.
• Larsen, S. 1967. Soil phosphorus. Adv. Agron. 19:151–210.
• Love, J.R. 1963. Mineral deficiency symptoms on turfgrass: I. Major and secondary nutrient elements. Trans. Wis. Acad. Sci., Arts Lett. 51:135–140.
• McLean, E.O. 1977. Contrasting concepts in soil test interpretation: Sufficiency level of available nutrients versus basic cation saturation ratios. p. 39–540. In T.R. Peck et al. (ed.) Soil testing: Correlating and interpreting the analytical results. ASA Spec. Publ. 29. ASA, CSSA, and SSSA, Madison, WI.
• Miller, G.L. 1999. Potassium application reduces calcium and magnesium levels in bermudagrass leaf tissue and soil. HortScience 34(2):265–268.[Abstract/Free Full Text]
• Mills, H.A., and J.B. Jones, Jr. 1996. Plant analysis handbook II. MicroMacro Publ., Athens, GA.
• Munter, R.C., and R.A. Grande. 1981. Plant tissue and soil extract analysis by ICP-atomic emission spectrometry. p. 653–672. In R.M. Barnes (ed.) Developments in atomic plasma spectrochemical analysis. Heyden and Sons, London.
• Nelson, D.W., and L.E. Sommers. 1980. Total nitrogen analysis of soil and plant tissues. J. Assoc. Off. Anal. Chem. 63:770–778.
• Normandin, V., J. Kotuby-Amacher, and R.O. Miller. 1998. Modification of the ammonium acetate extractant for the determination of exchangeable cations in calcareous soils. Commun. Soil Sci. Plant Anal. 29:1785–1791.
• Puhalla, J., J. Krans, and M. Goately. 1999. Sports fields: A manual for design construction and maintenance. Ann Arbor Press, Chelsea, MI.
• Rhoades, J.D. 1982. Cation exchange capacity. p. 149–157. In A.L. Page et al. (ed.) Methods of soil analysis. Part 2. 2nd ed. Agron. Monogr. 9. ASA and SSSA, Madison, WI.
• Rossi, N., P.H. Nye, D.L. Grunes, and C.A. Sanchirico. 1988. Prediction of the calcium to calcium plus magnesium ratio in soil-grown winter wheat forage. Soil Sci. Soc. Am. J. 52:152–160.[Abstract/Free Full Text]
• Sartain, J.B. 1985. Effect of acidity and N source on the growth and thatch accumulation of Tifgreen bermudagrass and on soil nutrient retention. Agron. J. 77:33–36.[Abstract/Free Full Text]
• Sartain, J.B. 1993. Interrelationships among turfgrasses, clipping recycling, thatch, and applied calcium, magnesium, and potassium. Agron. J. 85:40–43.[Abstract/Free Full Text]
• SAS Institute. 1996. The SAS system for Macintosh. Release 6.12. SAS Inst., Cary, NC.
• Smith, K.A., and A. Scott. 1990. Continuous-flow, flow-injection, and discrete analysis. p. 183–227. In K.A. Smith (ed.) Soil analysis, modern instrumental techniques. 2nd ed. Marcel Dekker, New York.
• Spiers, J.M. 1993. Calcium, magnesium, and sodium uptake in rabbiteye blueberries. J. Plant Nutr. 16:825–833.
• Spiers, J.M., and J.H. Braswell. 1994. Response of ‘Sterling’ muscadine grape to calcium, magnesium, and nitrogen fertilization. J. Plant Nutr. 17:1739–1750.
• St. John, R.A., N.E. Christians, and H.G. Taber. 2001. Supplemental calcium applications to turfgrass established on calcareous soils. Int. Turfgrass Soc. Res. J. 9:437–441.
• Suarez, D.L. 1996. Beryllium, magnesium, calcium, strontium, and barium. p. 575–601. In D.L. Sparks (ed.) Methods of soil analysis. Part 3. SSSA Book Ser. 5. SSSA and ASA, Madison, WI.
• Sumner, M.E., and W.P. Miller. 1996. Cation exchange capacity and exchange coefficients. p. 1201–1229. In D.L. Sparks (ed.) Methods of soil analysis. Part 3. SSSA Book Ser. 5. SSSA and ASA, Madison, WI.
• Thomas, G.W. 1982. Exchangeable cations. p. 159–165. In A. Klute (ed.) Methods of soil analysis. Part 2. 2nd ed. Agron. Monogr. 9. ASA and SSSA, Madison, WI.
• United States Golf Association Green Section Staff. 1993. USGA recommendations for a method of putting green construction. USGA Green Sect. Rec. 31(2):1–3.
• Wall, L.L., C.W. Gehrke, T.E. Neuner, R.D. Cathey, and P.R. Rexroad. 1975. Total protein nitrogen: Evaluation and comparison of four different methods. J. Assoc. Off. Anal. Chem. 58:811–817.
• West, J.W., and J.H. Reynolds. 1984. Cation composition of tall fescue forage as affected by K and Mg fertilization. Agron. J. 76:676–680.[Abstract/Free Full Text]
• Westermann, D.T. 1992. Lime effects on phosphorus availability in a calcareous soil. Soil Sci. Soc. Am. J. 56:489–494.[Abstract/Free Full Text]

This article has been cited by other articles:

				M. J. Schlossberg and J. P. Schmidt Influence of Nitrogen Rate and Form on Quality of Putting Greens Cohabited by Creeping Bentgrass and Annual Bluegrass Agron. J., January 1, 2007; 99(1): 99 - 106. [Abstract] [Full Text] [PDF]

This Article Abstract Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by St. John, R. A. Articles by Taber, H. G. Search for Related Content PubMed Articles by St. John, R. A. Articles by Taber, H. G. Agricola Articles by St. John, R. A. Articles by Taber, H. G. Related Collections Turfgrass Management Turfgrass Soil Chemistry