No-till alfalfa (Medicago sativa L.) establishment is the only environmentally sound procedure for alfalfa production on erodable land. Surface limestone application is the only reasonable method of placement in no-til1 systems with pH below 6.5. The purpose of this research was to evaluate surface limestone application vs. incorporation throughout the plow layer for alfalfa production in acidic soils. In this study limestone placement included: 1. incorporation during tillage operations, 2. surface application after tillage and preparation of seedbed, and 3. surface application without tillage. Limestone was applied at 0, 1.25, 2.50, and 5.00 tons per acre with each placement method. Limestone treatments were imposed on 30 Sept. 1986 in Montgomery County, VA (37° 1lâ N, 80° 25â W and 1950 ft. elevation) on a Groseclose silt loam (clayey, mixed, mesic Typic Hapludult) having a pH of 5.6 in the top 9 inches. Limestone treatments were imposed at a second site on 25 Nov. 1986 in Orange County, VA (38° l3â N, 70° 7â W and 515 ft. elevation) on a Davidson clay loam (clayey, oxidic, thermic Rhodic Paleudult) having a pH of 5.7 in the top 9 inches. 'Cimmeronâ alfalfa was planted using no-till procedures on 23 March 1987 in Montgomery County and on 26 Aug. 1987 in Orange County. Soil samples were taken about 2 years after limestone application at depths of 0 to 1, 1 to 2, 2 to 3, and 3 to 6 inches for surface applied treatments and 0 to 3, 3 to 6, and 6 to 9 inches for incorporated treatments. Soil samples w0ere also taken at a depth of 18 to 24 inches where limestone was incorporated during tillage at 5 tons per acre. Four harvests were made in 1988. At both locations, limestone application increased yields by 114 to 300% as compared with the check where no limestone was applied. Yields from plots receiving surface limestone application were equal to plots with incorporation at both locations. Tillage did not increase yields as compared with no tillage except in Orange County on plots where no limestone was applied. Soil pH increased from 5.6 to 6.8 at the 1- to 2-inch depths and from 5.6 to 6.3 at the 2- to 3-inch depths where 5 tons per acre of limestone were surface applied in Montgomery County. In Orange County, soil pH increased from 5.5 to 6.5 at the 1- to 2-inch depths and from 5.6 to 6.1 at the 2- to 3-inch depths where 5 tons per acre limestone were surface applied. Above pH 5.5, Al saturation was below 2.7% in Montgomery County and 0.7% in Orange County. Aluminum saturation averaged 9.0% and 4.6% where pH was between 5.0 and 5.5 in Montgomery and Orange Counties, respectively. At both locations, in the 18- to 24-inch depths a pH of 4.8 was not influenced by limestone incorporated at 5 tons per acre. Aluminum saturation at 18- to 24-inch depths was 51% and 62% in Montgomery and Orange Counties, respectively. These data indicate that surface applied limestone can produce first year alfalfa yields similar to yields obtained with incorporated limestone. / Master of Science

Sherwood Lake, a 165 acre public fishing impoundment in Greenbrier County, West Virginia, was treated with calcium carbonate for four years. The limestone treatment was done by revolving limestone drums installed above the lake on Meadow Creek. The limestone drum provided continuous treatment throughout the period. Limnological conditions of Meadow Creek and Sherwood Lake were monitored throughout the treatment period. Physicochemical and plankton data were collected monthly and the fish population sampled annually. The water quality of Sherwood Lake improved gradually during treatment, however, by the end of 1968 the lake could only be classified as a soft water lake. The growth of Elodea was encouraged by the addition of limestone. A lack of available nutrients and decreased productivity at higher trophic levels was attributed to the dense growths of Elodea. The mean annual volume of plankton decreased during lime treatment, however, this decrease was attributed to the usurping of available nutrients by higher aquatic plants. Low concentrations of available phosphorus was considered to be the major chemical factor limiting biological production. No significant growth increments were evident for any species of fish of any age that could be attributed directly to the limestone treatment of Sherwood Lake. An increase in the standing crop of fish was noted but could not be ascribed entirely to the addition of limestone. / Master of Science

Master of Science

To determine the most profitable rates of applying lime for different crops on different soil types in the State, and to determine if possible the hydrogen ion concentration for the most economic yields of the different crops on different soil types. Plots will be laid out at Blacksburg, Staunton, Williamsburg, Holland, and Martinsville, and limed at different rates, Yields will be kept of crops grown at each locality on limed plots and the hydrogen ion concentration will be determined for at least two localities. / M.S.

(1) The experiment as a whole showed that pH determinations may be made at any time throughout the year with assurance of being reliable as a relative indicator of lime requirement. (2) A comparison of the pH determinations made in 1928 with those made in 1930-31, show that the plats have become more acid. (3) The pH values of the soil paralleled the quantity of lime applied. Where no lime was applied the soil was found to be very acid, but increasing applications of lime brought the reaction gradually to the neutral point. (4) There appears to be a definite relation between pH and crop yield. For each crop the yields increased up to a certain pH; beyond which they decreased again. The optimum pH for the crops grown in the experiment reported here are as follows; Alsike clover 5.8 Red clover 6.3 Sweet clover 6.5 Soybeans 6.3 Wheat 6.2 Barley 6.2 Rye 5.9 Corn 6.3 Potatoes 5.4 / M.S.

M.S.

An investigation of the pH, organic matter content, total nitrogen, and cation exchange properties of the soil of the l8-year-old rotation plots at Chatham, Virginia, was carried out. Individual soil samples were taken of each of the 36 sub-plots which compose the experiment. After the chemical analyses were completed, the data obtained was analyzed statistically. As a result of this investigation, the following conclusions are presented: 1. Application of ground limestone which resulted in increased crop yields also tended to increasae organic matter and cation exchange capacity. 2. The lower soil reaction of the unlimed plots seemed to be more effective in retaining a larger percentage of the total dry matter produced as soil organic matter. 3. A significant positive correlation waa found between soil organic matter and cation exchange capacity. 4. There seemed to be no significant correlation between fertilizer treatments, crop yields, and carbon-nitrogen ratio. 5. Applications of different amounts of superphosphate and their combinations with muriate of potash and muriate of potash and nitrate of soda apparently has had no effect on the amount ot exchangeable calcium, magnesium, and hydrogen present. 6. Exchangeable potassium seemed unaffected by fertilizers not containing potassium, but showed a marked increase on the plots receiving potassium in a mixture. 7. Applications of ground limestone have resulted in large increases of exchageable calcium and magnesium, increases in exchangeable potassium and marked decreases in exchangeable hydrogen and pH values. Percentage base saturation was also greatly increased by pound limestone applications. / M.S.

[Truncated abstract] Standard AOAC methods of chemical analysis have been used to characterize and evaluate the industrial byproducts; partly burnt chicken litter ash (CLA), totally burnt chicken litter ash (CLAT), wood ash (WA) and iron smelting slag for use as a combined liming agent and phosphate fertilizer. Rock phosphate has this function and was included for comparison purposes. All the byproducts had pH values above 9 and a liming capacity above 90% of pure lime, as a result, these materials will be effective as liming agents. Total P concentrations for CLA, CLAT, slag, and WA were 3.6%, 4.75%, 0.26%, and 0.44% respectively indicating that they could be used as P fertilizers when applied at the high rates required for liming soils. ... The RE values for all the materials relative to monocalcium phosphate (100%) for the first harvest are as follows, 50% for dicalcium phosphate, 31% for rock phosphate, 7% for partly burnt chicken litter ash, 7% for totally burnt chicken litter ash and 1% for wood ash and slag. The RE values for the second harvest were 100% for monocalcium phosphate, 80% for dicalcium phosphate, 40% for rock phosphate, 10% for partly burnt chicken litter ash, 8% for totally burnt chicken litter ash and 2% for wood ash and slag. Data for subsequent harvests are not reported due to the death of many plants. Clearly chicken litter ash has appreciable value as a phosphate fertilizer whereas wood ash and slag are ineffective. Explanations for these differences in effectiveness are discussed in the text. An evaluation of the liming effect of the byproducts indicates that they may be used as a soil amendment on acid soils and are nearly as effective as standard lime (CaCO3). Byproducts are also sources of other plant nutrients so they may be regarded as a form of compound fertilizer and liming agent.

LD2668 .T4 1954 T51 / Master of Science

Thesis (MScAgric (Soil Science))--Stellenbosch University, 2005. / Soil acidity is one of the greatest limitations to crop production in most soils of the world. The increasing high costs of conventional liming materials have made it necessary to explore the possibilities of using cheaper substitutes. In South Africa, 16 million hectares of land are naturally acid while on the other hand, the country’s coalfired power plants generate 28 million tons of mostly alkaline coal ash per year, disposal of which is increasingly becoming difficult. The use of coal ash as an agricultural soil amendment while solving the liming needs of local farmers, may also present a safe and more economical disposal option. This study was carried out to evaluate the effectiveness of coal ash as an agricultural liming material. A greenhouse experiment was conducted using maize as test crop. A field experiment was also established on Beestepan Farm in Middelburg, Mpumalanga Province using dry beans as test crop for the first season. In both experiments, fresh unweathered coal ash from Duvha power station (CCE 10%), dolomitic lime (CCE 77%) and calmasil (calcium silicate slag, CCE 99%) were applied to acidic sandy loam soils in the presence or absence of gypsum. Both calmasil and dolomitic lime were applied at equivalent rates of 0, 1, 2, and 4 tons/ha, and rates of 0, 7, 14 and 28 tons/ha were used for ash. Gypsum was applied at a rate of 4 tons/ha. All treatments were applied in three replications. Results showed that liming increased soil pH, improved soil nutrient status and plant uptake of base cations, and enhanced yield. In the greenhouse, coal ash decreased exchangeable acidity from 13.0 mmolc/kg to 6.67 mmolc/kg, increased Ca levels from 200 mg/kg to 379 mg/kg, and increased Mg levels from 25.9 mg/kg to 42.0 mg/kg. Nitrate levels were also raised from 4.4 mg/kg to 14.8 mg/kg hypothetically as a result of the increase in the activity of nitrifying bacteria following a decrease in soil acidity after ash application. Maize yield in the greenhouse was not significantly affected by ash or by other liming materials, and the sufficient watering and consequent elimination of aluminium-induced drought stress is put forward as having masked crop responses to acidity. In the field, coal ash reduced exchangeable acidity from 10.0 mmolc/kg to 5.88 mmolc/kg, increased Ca levels from 71 mg/kg to 132 mg/kg, and increased Mg levels from 7.3 mg/kg to 17 mg/kg. The increase in bean yield from 958 kg/ha to 1724 kg/ha by ash was similar to that realized by dolomitic lime and calmasil. Gypsum had little effect on soil acidity, but it substantially improved soil Ca and sulfate levels, and enhanced bean yield in the field experiment. The study demonstrated that coal ash could be effective as a liming material, and underscores the need for a cost-benefit assessment of ash use necessitated by the relatively higher rates of ash required to obtain significant soil and plant responses.