Cycas is of cultural and religious significance to many different peoples. Cycas has considerable economic importance in horticulture. Cycas species contain unique and potent toxic compounds that have caused problems to people and livestock in contact with them, and are of interest to the pharmaceutical industry. The cycads are the sister group to all other extant seed plants. An understanding of the evolution of the cycads is important in understanding the evolution of all modern plants.
Cycads fix atmospheric nitrogen, important in maintaining health and fertility of soils.
The fixation mechanism is through a cyanobacterial symbiosis that is unique to the cycads.