Re: grass-specific herbicides

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Margaret,

 

I think you never recieved a civil, to-the-point response to your question..  To my knowledge, most of the currently-available grass-specific herbicides have sethoxydim as the active ingredient. This seems to be only moderately toxic to non-target species [see http://store.parsonspestcontrol.com/msds/SETHOXYDIM-MSDS.PDF], In the US, brand names include Poast, Vantage and Arrest.  A nurseryman friend has used this to rescue a wide range of shrubs in containers that had become overgrown with rhizomatous grass.  I haven't resorted to this YET, but have often needed to rip out otherwise nice mixed borders when grass became dominant, so it's very tempting.

 

Is this appropriate for what you're looking at?  -- I can't tell, but certainly rhizomatous grasses invading cushion plants or woody plants that are intolerant of tilling are often beyond "old-fashioned" weeding.  If you're dealing with shrub plantings primarily, have you tried mulching, with or without newspaper to smother patches of unwanted grass.  Note that allelopathy works both ways -- grass can suppress woody plants, but in the US, leaf-litter from eucalypts and related genera, and many of our own chaparral shrubs, does limit grass growth/invasion.

 

If you limit herbicide use to last-case spot treatments, follow safety advisories, and above all, keep the material from washing or blowing into food crop or resource land, I for one would applaud using this in your effort to restore native plantings.

 

loren russell

corvallis oregon

 

 

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From: "Richard Tiede" <rtiede@pacbell.net>
To: "Paul Reid" <pkssreid@comcast.net>, "Margaret A Healey" <Margaret.A.Healey@bigpond.com>, medit-plants@ucdavis.edu
Sent: Thursday, June 30, 2011 10:11:46 PM
Subject: RE: herbicides