What is the word that means of or pertaining to bushes?

Sylvestral means of, like or pertaining to trees. But, I haven't came across any word ending with -ine that defines "of, like or pertaining to bushes." Similarly, I haven't came across any words which means "of, like or pertaining to "shrubs", or "herbs", or "plants", or "weeds" etc.

Perhaps, the word dumose or dumous from latine dumosus, franch dumus meaning a thornbush, a bramble is defined in Webster 1913 as:

From Webster 1913 https://www.websters1913.com/words/Dumose

(Botany) Having a compact, bushy form.

As you say, you found this word in a science fiction book. The author might have coined the term to mean- of, or relating to bushes.

NOTE: We can form a word: dumosusine or dumusine, by adding suffix -ine meaning of or relating to bushes. Though, Google presents no search results of dumosusine or dumusine.