Fool's parsley is native to regions of Europe and adjoining parts of Asia and North Africa. In the modern era, it has been introduced to additional major regions, establishing itself in parts of temperate Asia and North Africa. Fool's parsley has shown adaptability to various environments outside its native range.

Fool's parsley is highly toxic to humans, cats, and dogs. All parts of the plant cause poisoning through ingestion, marked by severe gastrointestinal and nervous system symptoms like vomiting, diarrhea, tremors, seizures, and potentially deadly respiratory failure. Immediate medical or veterinary intervention is vital upon suspected ingestion due to its resemblance to non-toxic plants, increasing accidental ingestion risks.

Fool's parsley originated in Europe and Western Asia. This plant is notoriously problematic as a weed due to its aggressive ability to reproduce and spread. Specially, fool's parsley produces large amounts of seeds, which aids in its rapid and robust growth. Another significant feature that makes it a weed is its capacity to destabilize ecosystems by occupying large areas and excluding native plants. Fool's parsley is especially harmful to gardens because it can overtake and dominate garden vegetation, leaving little room for the growth of preferred plants. It can also have an adverse effect on crop yields in farming scenarios. The primary means by which fool's parsley spreads is through seed dispersal. Whether by wind, water, or through fauna, these seeds can be distributed across wide areas, thereby facilitating the plant's invasion of new territories.

The best time to remove 'fool's parsley' or Fool's parsley is during late spring to early summer, ideally before the plant starts to set seed.