Agricultural Science Commons^™

Bulletin 4283 - Nitrogen Fertilisers For Cereal Production, M. G. Mason

Bulletins 4000 -

Because fertiliser prices are high, it is important to understand what affects the response to fertilisers by crops.

Among the many factors influencing crop response to nitrogen applications, the most important are the season, soil type, paddock history, time of application and source of nitrogen. Before deciding whether to use nitrogen on a cereal crop, which source to use and at what rate, you need some understanding of how these factors work.

Greatest responses to nitrogen fertilisers can be expected in areas with a relatively long growing season. In such areas light soils with a low nitrogen status give the …

Bulletin No. 310 - The Influence Of Cropping On The Nitrogen, Phosphorus And Organic Matter Of The Soil Under Irrigation Farming, J. E. Greaves, C. T. Hirst

UAES Bulletins

Most soils contain sufficient nutrients for normal plant growth, with the exception of nitrogen, phosphorus and potassium. These elements are used by plants in the largest quantities and the amounts of these in the soil govern its productivity. Soil organic matter is of prime importance for it is the matrix which holds the nitrogen and modifies the structure, temperature, and water-holding capacity of the soil. The organic matter is the very life of the soil, for it is in and on it that bacteria work and by so doing determine the kind and speed of reactions which occur. It is …

Bulletin No. 274 - Influence Of Rotation And Manure On The Nitrogen, Phosphorus, And Carbon Of The Soil, J. E. Greaves, C. T. Hirst

UAES Bulletins

All agricultural plants require carbon, hydrogen, oxygen, nitrogen, calcium, potassium, magnesium, sulfur, phosphorus, iron, and probably traces of other elements for their normal growth and fruition. The growth of farm crops is dependent upon an available supply of these elements, and the extent of growth is governed by the one present and available in least quantity in proportion to the plant's needs. Of the essential elements, all plants secure two (carbon and oxygen) from the air, one (hydrogen) from the water, and the others from the soil. Most soils contain sufficient plant nutrients for normal plant production, with the exception …

Bulletin No. 185 - The Influence Of Nitrogen In Soil On Azofication, J. E. Greaves, D. H. Nelson

UAES Bulletins

Many soils of the arid west have a rich active azofying flora. This is due in no small measure to their composition. They are high in calcium and magnesium carbonate and contain a good supply of available phosphorus and potassium but have a low nitrogen content. They are poor in organic carbon; hence, their native supply of energy is limited. It is well-known that a liberal supply of rapidly decaying organic matter is beneficial, and this is being supplied to some soils in the form of manures. This will increase the nitrogen content of the soil. What effect will this …