crown vetch invasion of juniper

Asked March 28, 2020, 12:05 PM EDT

can Lontrel or clopyralid be used safely on juniper? If not what do you suggest for a safe post emergent herbicide?

Anne Arundel County Maryland

6 Responses

The label is the law for pesticides, and should include both weeds controlled and plants for which contact with the herbicide has been tested safe. The label for Lontrel, which contains clopyralid, is here: https://s3-us-west-1.amazonaws.com/agrian-cg-fs1-production/pdfs/Lontrel1c_Turf_and_Ornamental_Label.pdf. It indicates that some species of Juniper can be treated with this product, though the weeds controlled do not include Crownvetch (Securigera varia, which is different from the Common Vetch, Vicia sativa, that is listed). You may have to contact the manufacturer to ask if this product has been tested for use on Crownvetch.

Invasive plant sites discussing Crownvetch control do not have other herbicide recommendations for areas where desirable plants are also present. Physical removal, while certainly tedious, is the only other approach when damage to desirable plants needs to be avoided. In a home landscape, this probably means hand-pulling; in a larger-scale area, it could mean grazing by goats depending on whether the goats would consume the Juniper as well. Repeated removal of above-ground growth will gradually starve the plant of its food reserves and re-sprouting will diminish.

Miri

What kind of vetch is this..common, hairy, crown ???Your answer will dictate treatment to get rid of it in the juniper, Thanks so much!

What kind of vetch is this..common, hairy, crown ???Your answer will dictate treatment to get rid of it in the

juniper, Thanks so much!

The presence of what appear to be tendrils at the leaf tips would indicate "true" vetch, or Vicia species. Crownvetch does not have these tendrils. When the plants flower, they are easiest to tell apart, but based on what we can see in these photos, this appears to not be Crownvetch. We cannot see enough detail to determine which Vicia this is - perhaps Hairy due to the hairy foliage - but that would matter less than whether this was Vetch or Crownvetch, as the herbicide label does not separate species of true vetch.

Miri

I seem to have two choices

1. Lotrel which has clopyralid label says kills common vetch

2. Image which has amazaquin.. .... label mentions nutsedge which is also in our juniper but not nearly as widespread as vetch, label does not mention vetch

Can you give me a phone number if I am confused?


We do not have pesticide information hotlines, if that is what you are seeking. We recommend asking the manufacturer directly at the number they should have listed on the label if you need them to clarify which weeds are controlled and if the product (in the case of amazaquin) is safe for use on Juniper.

If in doubt about Juniper damage or herbicide safety, hand-pulling is always an option. We understand this may be the harder route, but if you are able, likely the fastest immediate solution.

Miri