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The most important results of thirteen fertilizer experiments on veld, extending over periods of five to twenty years, are dealt with. In general, with nitrogen fertilization climax grasses were replaced by grasses of a more pioneer type. Of the nitrogenous fertilizers used, ammonium sulphate maintained the best basal cover (urea not considered) and produced the greatest yield response (urea included) . Compared with ammonium nitrate, sodium nitrate and urea, it also displaced the climax grasses most rapidly, whilst urea had the slowest displacement effect. Above approximately 150 lb N per morgen p.a., urea gave the lowest hay yield on veld, but this might not have great economic implications. Strong and fairly consistent correlations were observed between summer rainfall (October to Match) and air-dry herbage yield, and better yields were obtained in dry years with adequate fertilization than in wet years without fertilization. The response of veld to N-fertilization in terms of crude protein production was much more marked than that of dry matter production.Weight gain and milk production were markedly increased by fertilizing veld, and the grazing period to maximum weight was extended in the case of sheep. Finally, weaknesses in the planning and results of past experiments are pointed out and suggestions are made for future research to answer the questions still unanswered. UITTREKSELVersing word gelewer oor die belangrikste resultate van dertien veldbemestingsproewe wat van vyf tot twintig jaar geduur het. In die algemeen is klimaksgrasse vervang dear grasse van 'n meer pioniertipe onder stikstofbemesting. Van die stikstofhoudende kunsmissoorte gebruik, het ammoniumsulfaat die baste basaalbedekking onderhou (ureum buite rekening) en die grootste opbrengsreaksie getoon (ureum ingesluit). Vergelyk met ammoniumnitraat, natriumnitraal en ureum het dit ook die klimaksgrasse die vinnigste vervang, terwyl ureum die studigste vervangingseffek gehad het. Bo ongeveer 150 lb per morg p.j. het ureum die laagste hooi-opbrengs op veld as gevolg gehad, maar moontlik het dit nie groot ekonomiese implikasies nit. Sterk en redelik bestendige korrelasies is waargeneem tussen die somer reënval (Oktober tot Maart) en lugdroëe hooi-opbrengs en beler opbrengste is in droë jare met voldoende bemesting verkry as in nat jare sonder bemesting. Die reaksie van veld op N-bemesting in terme van ruproteinproduksie was meer merkwaardig as dié van droëmateriaalopbrengs.Gewigstoename en melkproduksie is merkwaardig bevorder deur veld le bemes en die periode tot maksimum gewig is verleng in die geval van skape. Swakhede in die beplanning en resultate van vorige proewe word uitgewys en voorstelle word gemaak ten opsigte van loekomstige navorsing wat ten doel stel om vrae wat nog onbeantwoord bly te beantwoord. INTRODUCTIONVeld productivity is influenced by numerous factors. They may be grouped under the following headings : grazing management practices, botanical composition, soil productivity and climatic factors.Grazing management practices i...

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