A perennial herb that reproduces by seeds and by horizontal creeping roots.(noun)
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Use "whitetop" in a sentence
"Cheatgrass had moved in along with leafy spurge, Canada thistle and whitetop, all noxious weeds."
"Through the years I have written about various noxious weeds, including tall whitetop, knapweeds, Canada thistle, yellow starthistle, hoary cress and puncturevine."
"If you have ever tried to remove tall whitetop or Russian knapweed from your property, you know it is a multiyear battle that never ends."