Pre emergent herbicide on cocklebur

[Murray_KS]

Would anybody out there have any suggestions for a pre-emerg herbicide for cocklebur.  How long of a residual would it have also?

[Jim Meade / Iowa City]

The ISU weed book says for corn:  atrazine, Hornet and Sharpen.  For beans, First Rate.

[nwobcw]

Cocklburrs used to be our main weed problem.  We got rid of them with incorporating sencor back in the late 70s.

[Murray_KS]

How many seasons would you have to be hard on them (if they are a major problem), until you have them very well supressed?

[Pupdaddy]

If I remember right...through the fog of 30 plus years since I studied weed science...the cocklebur has 2 seeds in it's seed pod (the bur). One seed is immediately viable in the soil...and can emerge the next year. The other seed is a very well protected (hard seed coat) seed...that will last over 30 years in the soil. So...your control will slowly reduce the amount of immediately viable seeds in the seed bank...but you will almost certainly never get completely rid of them.

[cropdoc5]

Pupdaddy has it wrong.  Cocklebur seed will only survive 3 years max.  Control them 100% for 3 years and they will be gone until the seed is reintroduced from another farm that runs onto yours or a fur animal leaves them on your farm.  Have personally worked on farms to eliminate them and know that this works, but you have to stop and pick up any plants that escaped and produced seed, picking up said seed 100% for those 3 years as well.  Not easy, but can be done.

Cropdoc

[nwobcw]

All i know is that when we started incorporating treflan and sencor in about 1979 it was like a miracle.  Poof! Problem gone overnight.  I then started drilling beans in 1981.  The elevator agronomist told me back then a c-seed can lay dormant for 9 years but I have no proof of that.  Probably what he read in a book.