Results are given for the effects of heavy dressings of nitrogen, in the presence and absence of phosphorus and potassium supplements, on : dry-matter yield ; botanical composition of herbage ; contents of crude protein, phosphorus, potassium, calcium, magnesium, sodium and manganese. Brief reference is also made to the effects of the various experimental treatments on the uptake of certain other trace-constituents.The results indicate that high yields of pasture herbage having high protein and normal mineral contents can be maintained over a period of years by the use of fertilizer nitrogen, provided adequate fertilizer dressings of other major nutrients are given. Attention is drawn to various ion-antagonism effects that may influence the mineral composition of the herbage.In recent years pasture has acquired a steadily increasing importance as a crop in its own right. This is indeed in welcome contrast with the more or less incidental contribution that it made in early pastoral farming and, unfortunately, still makes in considerable areas of the British Isles. In the northern half of Great Britain, rotation or temporary pasture has long played an important part in the maintenance and improvement of the fertility of the arable land, and the importance of ley-farming systems is now well appreciated throughout the U.K. Even so, the term ' grassland ' still embraces land of widely varying agricultural value, ranging from rough mountain or heath, described, euphemistically in many cases, as used or capable of being used as grazing, through permanent grassland of indeterminate quality, to intensively managed and highly productive swards. It is necessary, therefore, in any consideration of the problems of the manuring of grassland, to define the category or type of grassland ; in particular, it is necessary to relate manuring to specific systems of management and utilization, to the botanical composition of the swards, to soil and climatic conditions and to other factors influencing manurial requirement. Manuring for the establishment and maintenance of pastureIn natural grazings and permanent grassland on unploughable land, substantial increases in output can be achieved by such remedial measures as good grazing management, surface cultivation, seeding and top-dressing with fertilizers. The maximum output of such land will normally, however, be much less than that of ploughable land and it is, of course, to the improvement of the latter that first consideration should be given. Although there are areas in this country where good grassland has been maintained over indefinite periods without recourse to ploughing, most ploughable pastures can with advantage be renovated by ploughing occasionally. Two main methods of laying down land to grass are : (I) undersowing a cereal crop, or occasionally a brassica such as rape, with grass and clover seeds, and ( 2 ) direct reseeding without a nurse-crop. The former is the more widely practised method, especially for rotation pasture. Treatment varies, of course, with soil and c...

Installation of pipelines causes soil disturbance with possible crop yield loss. Fertilizer and manure treatments may compensate for crop losses. Corn productivity was evaluated on five sites disturbed by pipeline installation in order to assess the relative sensitivity of soil types to the effects of pipeline construction during autumn and winter, and to determine the benefits of fertilizer and manure treatments. Trench, spoil bank, working side (ON-ROW) and undisturbed zones (OFF-ROW) as well as fertilizer and manure treatments were compared on three soils (Morrisburg loam, North Gower clay, Ste. Sophie loamy sand). Autumn and winter installation were compared on Morrisburg and North Gower soils. On the Ste. Sophie site only winter installation was studied. Pipeline installation did not affect corn emergence. On Morrisburg soil sites, autumn installation delayed silking, reduced plant heights and corn yields ON-ROW as compared to undisturbed soil; winter installation affected corn productivity only on the trench zone. On North Gower soil sites, pipeline installation had little effect on corn performance. At the Ste. Sophie site, installation resulted in delayed silking, and reduced plant height and yield in 1977 but improved corn yields in 1978. Fertilizer and manure treatments increased corn yields and accelerated silking at all sites. ON-ROW yields were not restored to OFF-ROW at the Morrisburg soil sites responsive to fertilizer treatments. Corn yield reductions were greater at sites with lower initial organic matter contents and higher initial bulk densities. Key words: Corn (Zea mays L.), fertilizers, manure, soil series, organic matter, bulk density

The paper reports the results for six factorial experiments carried out over a period of 3 years, and designed to measure the effects of nitrogen, phosphate and potash on the yield of dry matter and to determine the effect of nitrogen on the phosphate and potash requirements of grass being cut five times per annum for conservation.Heavy dressings of nitrogen reduced the percentage of dry matter in the fresh herbage, but produced a very large increase in the yield of dry matter. There were quite large variations in the response to this plant food, but 348 lb. N per acre per annum practically doubled the yield and generally the response curves were substantially linear.The response to nitrogen depended on an adequate supply of potash and at five of the centres there were very large interactions between these two nutrients. The need for potash was greatest at the highest nitrogen rate and was much greater in the second and third than in the first year of the experiments.At the highest nitrogen rate some of the responses to potash were very large. The yields of dry matter showed no large or consistent differences between applying 336 lb. K2O in one dressing during the winter months or applying this amount in five equal dressings, one for each cut. The results demonstrated the ability of the soils to supply potash and showed that the regular cutting and removal of herbage, especially if heavy dressings of nitrogen were applied, exhausted the potash reserves in the soil.Phosphate had practically no effect on the yield of dry matter either in the presence or absence of nitrogen.With adequate potash the production of dry matter per lb. of fertilizer nitrogen was practically independent of rate and the overall mean results are between 14·0 and 15·7 lb. In the absence of fertilizer potash there was a very large effect of rate: 15·0 lb. dry matter per acre was produced per lb. N with the 87 lb. N per annum treatment, 13·7 lb. with 174 lb. N and 10·0 lb. with the 348 lb. N treatment.Approximately 70–75% of the annual production was obtained before the end of July. Thus 1 lb. of fertilizer nitrogen produced considerably more dry matter per acre during May, June and July than later in the season.

in mngiiesiuiii niid mn&nesiuni-nlumiiiiuni nlloys. Oiico rccogiiised, effects of this sort are ensily remedied by iiinking st.niidnrc1 nut1 snriiple soliitioiis similnr in composition.dj'JJJ~;CUliOJIS Of the IIlClhOd Tlie follosiiig determiiintioiis nrc rcgiilnrly iiinde in t.liis Lnborntory.. (I) CnIciiiiii niid sodium iii iiingiiesiiim iiid nluniiiiiuui powders nild nlloys. To 1 g. of the iiietnl 6 nil. of wnter nut1 15 nil. of coiicelitruteil Iiydrochloric ncid solut.ioii nro ntltlcd nut1 the solutioii is iiiutlc up witli water to 50 iiil. This soliitioii is sprnyed. Stnridurds nrc prepred froiii iiict.nl substn~itinlly free from the impurities to be detcriiiiucd, to wliicli kuowii niiioutits of stnndnrd solutions of tlic npproprintc elemelits iire ntlded. Copper, mnugnricsc, niid riing~icsiuiii (the lnst in nlumiiiium) mny nlso be cletermitied.(2) Rubidium nut1 cicsiiim iii pntnwiiiin chloride precipitates. The snmplc (0.25 g. per 50 iiil. or proportioii-*

No abstract