Herbage analysis

Eaithfull, N.T. (1970) Automated methods in herbage analysis. MSc. thesis. University of Wales, pp. 32-36. 

Sulphur deficiency can be a problem in second and subsequent silage cuts. Compound fertilisers should be used to apply about 40 kg/ha SO if deficiency is confirmed by herbage analysis. 

Flandin F, Buffevant C and Herbage D (1984) A differential scanning calorimetry analysis of the age-related changes in the thermal stability of rat skin collagen. Biochim Biophys Acta 791, 205-211. 

Chemical separation techniques can be used to reduce spectral interferences and concentrate the analyte. These techniques include solvent extraction(39) and hydride generation(39, 46, 47). At Imperial College, the hydride generation technique is being used on a daily basis(46) for the analysis of soils, sediments, waters, herbage, and animal tissue. The solvent extraction technique is ideally suited for automated systems where the increased manipulation is carried out automatically, and a labor intensive step and sources of contamination are avoided. 

The total number of samples will be determined (above), but the batch size should be chosen to process the samples ready for analysis. There will boiling units, heating blocks and shakers etc., so mize throughput. If an herbage batch size for a advantageous if he added half of the following batch for analysis to 120. This is because of the... 

If the analysis is to be carried out in a similar way to total N in herbage, by acid-digestion in test tubes in an aluminium block followed by a colorimetric autoanaiysis procedure, then take a 0.5-g sample of air-dry soil. If serious frothing occurs, take 0.2 g soil, and adjust the calculation accordingly. Reducing the amount to 0.1 g may give peaks which are too small to be read with confidence. See Chapter 7 (pp. 138-141) for details of standards, reagents and method. 

Ronziere, M-C., Herbage, B., Herbage, D., and Bemengo, J-C. (1998). Fourier analysis of electron micrographs of positively stained collagen fibrils Application to type I and II collagen typing. Int. J. Biol. Macromol. 23, 207-213. 

Herbage. Herbage samples must be milled to pass a 1 mm aperture before analysis. This can be achieved by means of a beater mill with a carbon steel construction (as produced by Christie and Norris Ltd., Broomfield Road, Chelmsford, Essex, U.K.). This device introduces no detectable concentration of foreign metals into the sample. A small hammer mill is also satisfactory, but may contaminate the sample slightly with traces of nickel and chromium. 

Analysis of herbage (of forage) has sometimes been used to detect and identify radionuclides deposited from the atmosphere (Jackson et al., 1981). However, the problem arises that when the deposition rate is low, large areas of vegetation need to be sampled for detection. In the case of plutonium, an alternative is to collect the faeces of grazing animals such as cows, sheep and rabbits. Plutonium is very poorly absorbed by the mammalian gut and so virtually all that is ingested by an animal will appear in its faeces. Also, if the species selected obtains its food entirely by grazing, then the isotopic ratio Pu will be the same in the faeces as deposited on the... 

Soil analysis is beset with the further complication that samples have to be taken from different depths, to reflect movement of nutrients during the seasons. Precision agriculture is focusing renewed attention to the selection of methods of sampling flelds, in order to improve the efficiency of fertilizer use. Here the controversy is whether analysis of plant material is more practicable than soil analysis in provision of the necessary information. Plant material, such as grain or herbage, is more readily applicable than soil analysis, as well as being more amenable to analysis by NIR. It also reflects nutrients that are available to the plant. 

Table 3 gives a comparison of rates of depletion of essential trace elements for mineral soils of average trace element content [5], for herbage crops of normal trace-element composition. The herbage levels are based on the analysis... 

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