This is a public-interest archive. Personal data is pseudonymized and retained under GDPR Article 89.

Re: weeds

Crown vetch here in central Iowa the most difficult plant to eradicate from
a prairie, because of its growth form.  I have been fighting it for the past
7 or 8 years in one area that adjoins a roadside which I have sprayed out
continually, and it is still popping up each year from old seed.  When we
burned the roadside last year, it scarified thousands of seeds and new
plants came up everywhere, and there had not been a flowering plant on that
slope for more than 5 years.  

Sweet clover can be removed by late season fire in successive years and
hand-pulling.  It still shows up in old plantings, but the incidence of it
gradually decreases each season.  

Canada Thistles will be eliminated by competition for rootspace and good
species diversity in 5 or 6 years.  Our plantings more than 8 years of age
have no Canada thistles.  We still, however, pull them in new
reconstruction's when they are in the bloom stage.  

Red clover also appears to decrease as the planting ages and root space
fills up.  We dig red clover, but where it is a serious problem, we are
spraying it with Round-up in early November to kill the mature plants.  This
also scarifies old seed so you need to follow up on the procedure in
successive seasons.  

Curly dock plants will decrease in size each season and nearly disappear by
the 5th or 6 growing season.  You do need good species diversity to combat
it, however.  We also dig curly dock which really helps reduce the problem. 


Alfalfa in a good planting may live a very long time.  We still have plants
in one 9 year-old site, and I believe they are the same plants.  It is
nearly impossible to dig out, but easy to wick with Round-up.  Don't plant
in an old alfalfa field until you have planted it to corn or soybeans for a
couple of years.  

Smooth Brome is of little consequence in a good diverse planting.  Where is
is a problem consider spraying with Post (a grass herbicide for soybeans
about the 1st of May) after a spring burn. Late spring burns also tend to
set back brome as well as other cool season grasses.  

Reed canary grass is a serious pest in most wet-mesic sites in our area. 
Good species diversity helps.  We also wick it with a 30% Round-up solution
just before flowering and get very good control.  You can also try Post
after spring green-up.  Fall applications of Roundup when other plants have
stoped growing can also be very effective, however, reed canary grass needs
to be mowed in September to remain green until freezing weather.   

Annual weeds which are disturbance oriented all seem to disappear rather
quickly and are really good at holding the soil in new plantings.  I just
consider them a nurse-crop and keep them mowed during the first year after
planting.  

One plant not  on this list is bird's foot trefoil, which is nearly
impossible to eradicate from a planting once it is introduced.  I don't
think it is quite as bad as crown vetch, but I am making a serious effort to
eliminate is from adjoining roadsides in our area.  And it is not an early
task.  

Carl Kurtz

----------
>From: MJ Hatfield <oneota@ames.net>
>To: Prairie L <prairie@mallorn.com>
>Subject: weeds
>Date: Fri, Jun 25, 1999, 7:39 AM
>

>I'd like to ask you folks who are working with restoration and
>reconstruction of prairie to list the weeds in order of nastiness, and
>explain why. And perhpas list your method of preferred control. Feel
>free to add to the list.
>
>The reason I'm asking is that there is only so much time to work on weed
>eradication and I'd like to know your thoughts as to where effort should
>be placed.
>
>Thanks.
>===============================
>sweet clover
>crownvetch
>wild pasnips
>Canadian thistle
>Reed's canary grass
>dock
>Queen Anne's lace
>bull thistle
>red clover
>brome
>alfalfa
>creeping charlie
>dandylions
>foxtail
>mustards
>
>
>---------------------------------------------------------------------
>To sign-off this list, send email to majordomo@mallorn.com with the
>message text UNSUBSCRIBE PRAIRIE
---------------------------------------------------------------------
To sign-off this list, send email to majordomo@mallorn.com with the
message text UNSUBSCRIBE PRAIRIE
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index