Hogweed, giant (Heracleum mantegazzianum)

glyphosate

Rate 1.5 lb ae/a

Time Apply in spring during the bolting stage.

Remarks Avoid physical contact with the plant.

Caution Controls grasses as well as other vegetation in treated area.

Site of action Group 9: inhibits EPSP synthase

Chemical family None generally accepted

glyphosate (Roundup Pro Concentrate)

Rate Inject 5 ml of a 5% v/v solution into each leaf cane.

Time Inject with a hand-held device, into one leaf cane per plant 12 inches above root crown.

Remarks Mark each plant when injecting it, to avoid re-treating the same plant.

Caution Non-crop use only. Total of all treatments must not exceed 8.5 quarts/a of Roundup Pro Concentrate or 1,600 plants/a.

Site of action Group 9: inhibits EPSP synthase

Chemical family None generally accepted

imazapic (Plateau)

Rate 0.188 lb ai/a

Time Apply in spring during the bolting stage.

Remarks Avoid physically contacting plant when applying. Add an appropriate adjuvant to spray mix.

Caution Consult label on where Plateau can be used. Before using, note crop rotation restrictions.

Site of action Group 2: acetolactate synthase (ALS) inhibitor

Chemical family Imidazolinone