Page 129 - Nutrient Management Planning Guide

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Chapter 4.1

Obtaining Dimensions of a Pile

Some pile dimensions can be measured directly using simple devices such as a tape measure. Direct measurement of other dimensions, such as height and diameter, may not be practical or safe. These must be estimated using indirect means.

Estimating the Height of a Pile »

Simple mathematical relationships between the lengths of the sides of a right triangle (i.e., triangle with a 90 degree angle) can be used to estimate the height of a pile. Lean a piece of wood (e.g., a 2 × 4) of known length against the pile, with one end on the crest of the pile and the other end on the ground (Figure 4.1.3).

Figure 4.1.3 Using a Board to Estimate Height of a Pile (the “leaning 2x4” method)

Select an arbitrary point somewhere along the length of the board. Using a tape measure take the following measurements from this arbitrary point:

The vertical distance from the point to the ground •

directly below. The distance from the point to the edge of the board •

resting on the ground.

The ratio between these two measurements is identical to that between the height of the pile and the total length of the board. Multiplying the length of the board by this ratio will yield the height of the pile.

Key Mathematical Relationship of a Right Angle Triangle

Figure 4.1.4 Labeled Right Angle Triangle

The graphic (Figure 4.1.4) represents a right angle triangle with the sides labeled in terms of angle ‘A’. Any of the sides or angles of a right-angled triangle can be solved if the measurement for at least one angle (in addition to the 90 degree angle) and one side are known. This mathematical principle will be used to calculate the height of manure.