The varieties where adapted to the soil, climate and special irrigation techniques used in this region. (fieryfoodscentral.com)
The more complex the process (i.e., more complex irrigation techniques and similar) may require additional learning, through a course, degree, or mentorship. (articles.bplans.com)
Between them they were responsible for the earliest known writing, establishing mathematical principles and laws, developing irrigation techniques, the wheel and much else. (bookbrowse.com)