On 5/12/2012 6:31 PM, Nate Nagel wrote:
....

So the question. Now that we've done the heavy lifting, is there any
kind of herbicide that I could use that won't kill the boxwoods? I've
tried to pull everything that I could but apparently there are some
weeds with long-established, deep roots that might best be killed by
other methods.
....

Not if you get it on the foliage of the boxwoods, no.

2,4-D or hyphosate (Roundup) if _carefully_ applied only to the leaves
of the undesirables won't hurt the boxwood as it won't be taken up
through the soil in enough concentration to hurt (as long as you don't
just drown stuff, anyway).

But there's no broadleaf herbicide that will get ivy or poison oak or
whatever it is you've got in there that won't also get the shrubs if
overspray.

Do not use anything that claims to be ground or root-acting; they'll be
the ones that are taken up through the soil and really hurt badly.

If careful you may burn a few leaves but likely will not do any
significant damage; there's so much foliage there that unless you really
cover a significant fraction of it the damage will be pretty well localized.

I'd still suggest actually identifying the weed species as well as the
shrub; contact a nursery or local county extension office and ask for
advice. Sight unseen diagnoses are risky despite generalities that are
so in general.

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