Ragweeds are a type of plant that produces pollen that can cause allergic reactions like hay fever. There are several synonyms for ragweeds, including ambrosia, bitterweed, and hogweed. Another common synonym for ragweeds is the genus name, Ambrosia. This group of plants is common in North America and includes 41 different species. The most well-known species of ragweed, Ambrosia artemisiifolia, is a common weed found in fields, meadows, and along roadsides. Ragweeds can be harmful to humans and animals, so it's important to be aware of their presence and take steps to avoid exposure.