Type - Residue is defined as fragile or
non-fragile depending on rate of decomposition by weathering
and reduction of residue cover by harvesting and tillage
Residue - Crop residue that is generally damaged
passing through the harvesting unit or through weathering.
Crop stems are small in diameter; leaves are small in size
and fall from the plant before harvest. Many fragile
residues have a high nitrogen content that favors microbial
breakdown. Examples of fragile residue include Canola,
Cotton, Potatoes, Soybeans, and Sugar Beets.
3. Non-Fragile Residue -
Crop residue that is individually large in size and durable
to harvesting and weathering. The total mass of residues
produced is great. Examples of non-fragile residue include
Corn, Barley, Rice, Sugarcane, and Tobacco.
Residue - Residue cover in a field prior to a
tillage pass. Starting residue can be determined through the
line-transect method, photo comparison method, or the
5. Line-Transect Method - Method
for estimating residue cover on the soil surface. A rope or
tape measure with 100 equally spaced points is stretched
diagonally across crop rows. Each point over a piece of
residue is counted to obtain an estimate of residue cover.
Comparison Method - Method to estimate residue by
comparing residue cover to photographs of known residue
Method - Method to estimate residue cover through
multiplying starting residue by estimates of the percentage
of cover following tillage passes.
8. Remaining Residue -
Estimated residue cover after a tillage pass.
9. Overwintering Factor - Residue
losses from the climatic effects of over-winter weathering.
Residue losses are particularly dependent on precipitation
and temperature. Winters and regions with long periods of
snow cover and frozen conditions may have marginal
reductions in residue cover. Winters and regions with warmer
conditions and high precipitation may have significant
losses in residue cover.
10. Tillage Pass - Any
single tillage operation in the sequence of operations that
manipulates the soil to produce a crop.
Tillage - Tillage passes deeper than 6 inches
depth. Generally done in high residue conditions with a
moldboard plow, chisel plow, deep ripper, or primary disk.
Primary tillage fractures and loosens soil and mixes residue
into the soil.
12. Secondary Tillage -
Tillage passes shallower than 6 inches performed with the
intention of leveling soil, breaking clods, incorporating
residue, or preparing a seedbed. Secondary tillage passes
may or may not be preceded by a primary tillage pass.
13. Crop Care Tillage -
Tillage passes following seed germination. Crop care tillage
kills weeds, increases aeration, and improves water
infiltration. Crop care tillage tools include row crop
cultivators and rotary hoes.