"Undisturbed soil" refers to soil that has not been altered, dug up, or disrupted in any way. It is in its natural state and has not been disturbed by human activities or natural processes. Full definition
Instead of the traditional practice of plowing land and discing or harrowing it to prepare the seedbed, and then using a mechanical cultivator to control weeds in row crops, farmers simply drill seeds directly through crop residues into undisturbed soil, controlling weeds with herbicides when necessary. (insteading.com)
Dennis says the advantages of concrete slabs include building on grade over undisturbed soil, if conditions allow, which means the required labor, excavation, and forming costs can be held to a minimum. (rismedia.com)
«Unfortunately, Rhizoctonia persists in undisturbed soil and serves as annual reservoir of this fungus which is most pronounced in undisturbed direct - seeded fields.» (news.wsu.edu)