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Winter wheat is grown as a cash crop or a cover crop.Optimal growing conditions for winter wheat include high-drainage soil with medium texture. Mid-quality soil nutrient content is best for winter wheat, with an appropriate supply of nitrogen being critical for the wheat to be able to establish itself in time before winter dormancy.
Photograph taken 21 March 2010 in Norwich, Vermont. Frost heaving (or a frost heave) is an upwards swelling of soil during freezing conditions caused by an increasing presence of ice as it grows towards the surface, upwards from the depth in the soil where freezing temperatures have penetrated into the soil (the freezing front or freezing boundary).
Lodging is the bending over of the stems near ground level of grain crops, which makes them very difficult to harvest, and can dramatically reduce yield. Lodging in cereals is often a result of the combined effects of inadequate standing power of the crop, and conditions such as rain, wind, hail, topography, soil, previous crop, and others. [1]
Cultivation, earthworms, frost action and rodents mix the soil and decrease the size of the peds. This structure allows for good porosity and easy movement of air and water. This combination of ease in tillage , good moisture and air handling capabilities, and good structure for planting and germination , are definitive of the phrase good tilth .
Spring wheat does not undergo dormancy. Wheat requires a deep soil, preferably a loam with organic matter, and available minerals including soil nitrogen, phosphorus, and potassium. An acid and peaty soil is not suitable. Wheat needs some 30 to 38 cm of rain in the growing season to form a good crop of grain. [123]
Frost weathering is a collective term for several mechanical weathering processes induced by stresses created by the freezing of water into ice. The term serves as an umbrella term for a variety of processes, such as frost shattering, frost wedging, and cryofracturing.
Soil bulk density is equal to the dry mass of the soil divided by the volume of the soil; i.e., it includes air space and organic materials of the soil volume. Thereby soil bulk density is always less than soil particle density and is a good indicator of soil compaction. [ 47 ]
They range from temperate to hot-arid to cold semi-arid. Scenarios based on increasing temperature by up to 2.5 °C (4.5 °F) and rainfall decreases by up to 25% show wheat grain yield losses can be significant. The losses can be as much as 45% in temperate areas and over 50% in hot-arid areas. But in cold semi-arid areas yields can be ...