I can't read the article, but is 'more herbicides' referring to a larger quantity of the existing herbicides or a greater variety of herbicides? If it's the lat

I can't read the article, but is 'more herbicides' referring to a larger quantity of the existing herbicides or a greater variety of herbicides? If it's the latter, the author's sentence is fine. If it's the former, I agree that the redundancy is unhelpful. Also, you should not bracket parenthetical statements with dissimilar punctuation marks.