5-10-20 contains 5%N, 10% P - UMD

BD = bulk density. PD = particle density. Example: Laboratory analysis of a soil indicated that it has a bulk density of 1.08g/cm3 and a particle density of 2.60g/cm3. What is the percent porosity of this soil? % PS = 100 - (1.08/2.60 x 100) = 100 - (41.5) = 58.5 ~ 59% ................
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