Sentence:  Perhaps the BBC could get the Radio 2 King of the Tomatoes to come back and tell us what programmes to play to discourage rampant growth in minor forests of giant bindweed, monster nettles and apprentice <WSD>triffids</WSD>. 
Meaning of the word marked with <WSD> tags:  Any large, fast-growing and hard-to-remove weed, such as the flowering shrub (species).