Beech control with triclopyr versus glyphosate

[Peter Smallidge]

[I'm pasting from a recent email thread]

Question - 

I'm working on a couple beech regen and mid story control projects.   I have been using Garlon 4 in oil.   Works good, but sometimes I want it to move through the roots and the Garlon doesn't do that.   Looking on line this morning I saw your name come up on a couple things.   

 Have you had good luck with glyphosate as cut stump?  Stump diameters from 1/2" to 8".  I haven't used glyphosate for that.    I'll use rodeo because thats why I have for foliar work.   Looking at active ingredient requirements, I'm guessing that glyphosate for cut stump needs to be at 50% mixture.   

My response - 

Rodeo has glyphosate as its active ingredient.  As you note, glyphosate is mobile in the plant and garlon (triclopyr) is not. Cut stump or cut surface treatments with glyphosate will flash into the root system to kill beech suckers, and there is no known evidence that it will move into any other species.  Use a minimum of 25% active ingredient, but 40 to 50% active ingredient is slightly better.  A couple links for beech

https://blogs.cornell.edu/cceforestconnect/files/2015/12/seasonal-b...

https://blogs.cornell.edu/ccednrpublications/files/2015/03/american...

 

I use both Rodeo and Accord XRT II. Both have glyphosate at about 50% active ingredient so you can cut with water up to 1:1 to achieve a 25% active ingredient.  I often use 3 or 4 parts of product to 1 part water…just enough water to ease the flow through the sprayer.  Here’s a refresher on how to mix to achieve a desired concentration.  https://blogs.cornell.edu/cceforestconnect/files/2015/12/Mixing-her...

 

Rodeo does not have a surfactant, but Accord XRT II does. I’m not aware of any advantage or not to the surfactant for cut-stump treatments.  The bigger the stump the more chemical that is available to move into the root network. Also, bigger stumps by default have a greater reduction in the basal area of standing trees that otherwise horde the glyphosate (e.g., bigger trees make bigger stumps which is good because the stump has more surface and the tree is removed from the connection).  The small stumps are likely connected to a larger stump (or not) and thus would not need to be treated. They have such little surface area that they don’t move much glyphosate into the root network. No harm in treating the small stumps, but likely not much benefit.

 

I’ve had good luck with flash in beech during October, likely the same through middle November. Not sure about December. There is almost no flash when the wood is frozen.

[Freyda Lynn (Black)]

Thanks for referencing the two articles. Two questions after reading them.

1. Could you please give the details of the updated "drill and fill" option to "hack and squirt" that you discussed in the MFO training in the field? (or reference any already written update).  

2. The link given in the biblio of "American Beech Fact Sheet" for looking up a NYS registered pesticide (http://magritte.psur.cornell.edu/pims/current/) appears to no longer be functional. Could you reference the correct path?

thanks!

[Peter Smallidge]

Hi Freyda:

Thanks for the note and identification of the broken URL.

Regarding "drill and fill" - This technique uses a 3/8" diameter drill bit with a brad point (or spade bit) to create a hole that is about 1 inch deep at a 45 degree angle in the tree being treated. A hole of this diameter, depth and angle results in a volume of about 1 ml, which is the dose per each three inches of tree diameter for the application of the concentrated treatment with products such as Arsenal or Accord XRT II (not an endorsement; also see the label for details of "concentrate").

Here is the link for NYS registered pesticides.

http://www.dec.ny.gov/nyspad/products?0

[Joanne Vaughn]

Wondering if garlon (triclopyr)  could also be used to control sprouting black locust without killing the original tree.