A thyrsus is a staff of giant fennel covered with ivy vines and leaves.

For giant fennel, see Ferula communis.

Other species of the genus Ferula are also commonly called giant fennel, but they are not culinary herbs.

Many plants of this genus, especially F. communis are referred to as "giant fennel," although they are not fennel in the strict sense.

It is commonly believed to be a now-extinct plant of the genus Ferula, perhaps a variety of "giant fennel".

Most notable for this use is the extinct giant fennel, silphium.

Now we are at lower altitudes, new species appear: euphorbia, giant fennel, flamboyant ferns, different species of wild rose and the yellow Roman orchid.

In its native range, it is frequently confused with the similar-looking Ferula communis, the giant fennel.

It is one of the components of asafoetida, the dried latex from the giant fennel (Ferula communis).

This giant fennel looks fantastic as a centrepiece for a sunny herb garden, or among tall perennials and grasses.