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
Holly, English (Ilex aquifolium)
Methods of control include pulling, and herbicides applied to cut stumps, cut surfaces (such as hack and squirt), by injection into the stem, and as (topical) basal bark/stem treatments (12 to 15 inches above ground cut). Pulling is partially effective if stems are very small. Refer to the forestry section (M) in this handbook for more complete discussion about specific application methods and rates..
glyphosate
Rate 0.75 to 1.5 lb ae/A
Time Fall and late spring
Remarks 50% control if applied to frilled stems. Cut stump treatments may result in excessive sprouting with very poor long-term control. Fall treatment most effective. Injection and hack and squirt applications of glyphosate into stems may be more effective in the spring than in the fall
Site of action Group 9: inhibits EPSP synthase
Chemical family Glycine
imazapyr (Arsenal, Chopper, Ez-Ject Copperhead Herbicide Shells)
Rate Cut stump treatment: undiluted
Cut Surface Applications (hack and squirt): 1 ml of 50% solution at intervals of 3 to 4 inches between cuts
Injection: 1 ml of dilute solution in each injection, separated by no more than 3 inches.
Time Fall or late spring
Remarks Very effective If injected into stem. No more than 1.5 lb ae/A/yr (96 fluid oz/A).
Site of action Group 2: acetolactate synthase (ALS) inhibitor
Chemical family Imidazolinone
triclopyr (Element 4, Garlon 4 or Garlon 3A)
Rate Cut stump treatment:. Undiluted
Cut Surface Applications (hack and squirt): 1 ml of 50 to 100% solution at intervals of 3 to 4 inches between cuts.
Basal bark treatment: 20 to 30% solution in oil (low volume) or 1 to 5 % solution in oil (high volume)
Injection: 1/2 to 1 ml of undiluted Garlon 3A at intervals of 3 to 4 inches between centers of the injector wound
Time Fall and late spring
Remarks Applying triclopyr to frilled stems is very effective in both seasons. May be applied at a rate of up to 6 lb ae of triclopyr per acre per year.
Site of action Group 4: synthetic auxin
Chemical family Pyridine