Roundup, them disc-how long?

Crimson850

Member
a bit late getting my brassica plots ready, but getting ready to spray roundup on the weeds and grasses that are there now, how long do I wait until I disc and prep the seedbed after I spray?
 
I like to wait a week but I doubt that is necessary. Depending on the weeds you have and how mature they are you may have a hard time killing them or simply be adding their seed to the soil. I would broadcast then spray and either roll or mow the weeds to form a thatch over the seed. You won't hurt hard seed.
 
2 weeks makes it easier to disc. I've also done it the next day...it's just a lot more effort to break up the soil.
 
I'm going to give it a few days then disc it, breaking up the soil is usually pretty easy with the disc that I have, I just want to spray what's there now to eliminate as much competition as possible
 
Ok. I'll go with it. I wanted to ask why chemically kill it when you were going to mechanically kill it, too. But, I won't because I found myself doing the same thing last week!

In the lab, plants treated with glyphosate are tested 3, 5, and seven days after. Absorption and translocation are two different issues, just to be clear here. While absorption is required to get started, translocation is what kills.

In round, round number glyphosate is into less than 30% of the plant in three days -- in a lab. At seven days, the translocation is nearly complete -- in a lab.

Outside of a lab where the conditions affecting translocation are uncontrollable, times may double - or more.

Practically, five days would seem to be a minimum time to wait.
 
I was going to ask the same question. If you have equipment and killings the vegetation is not necessary before why spend the effort. Dead is dead whether from spraying or tillage.

Here is where I find spraying the most beneficial in a burndown situation: large amounts of grasses which hold onto the soil making mechanical cultivation problematic.


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Let me ask this, how long until gly is "rain proof"? I am hoping to spray this evening, with rain expected tomorrow.
 
I sprayed tonight, after dark. It has been so hot the last few days. I'm using a 50gallon 3 point, PTO driven spot sprayer. We built a platform on the back so someone can ride and spray while someone else drives the tractor. A boom sprayer would just not work where I am planting. Going to disc in a few days, hoping I can get a good kill by then. I added just slightly over 1 gallon of gly to 50 gallons of water.
 
That's my mistake. I was under the impression that was the proper rate for 50 gallons. I don't guess it can hurt anything, other than just a waste of gly (money)
also I have heard it is less effective if you spray on real cloudy days or in the dark. I don't have first hand experience with that, I would really like to know how it works out for you, just to see if there is any merit to it.
 
I sprayed tonight, after dark. It has been so hot the last few days. I'm using a 50gallon 3 point, PTO driven spot sprayer. We built a platform on the back so someone can ride and spray while someone else drives the tractor. A boom sprayer would just not work where I am planting. Going to disc in a few days, hoping I can get a good kill by then. I added just slightly over 1 gallon of gly to 50 gallons of water.
Use AMS and crop oil to make your mix more potent, cut back on the gly, and you will get better burn down results.
 
Use AMS and crop oil to make your mix more potent, cut back on the gly, and you will get better burn down results.
I just bought a 50 lb bag of spray grade AMS. I had never used it before but I saw an earlier post about it making the gly more effective and being able to use less gly. I just tried a tank this past weekend and yesterday it looked like it was working good. Does anyone know if AMS can be used the same way with clethodim to make it more effective.
 
I just bought a 50 lb bag of spray grade AMS. I had never used it before but I saw an earlier post about it making the gly more effective and being able to use less gly. I just tried a tank this past weekend and yesterday it looked like it was working good. Does anyone know if AMS can be used the same way with clethodim to make it more effective.
Yes, I always use it with clethodim, it's recommended right on the label. Some clethodim labels say AMS not recommended for clover because it may make it to potent and burn the clover, however, I'm using it on clover all the time and have never had a problem. It makes the clethodim more effective on some of those hard to kill weed species. I'd use crop oil as well.
P.S. Remember to always put the AMS in the water first.
 
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That's my mistake. I was under the impression that was the proper rate for 50 gallons. I don't guess it can hurt anything, other than just a waste of gly (money)

I don't think its bad at all. Personally I don't go to the field with less than a quart per acre, and 10gal of water per acre. That's right about 3oz/gal. Along with AMS and crop oil. Never had a problem with killing anything
 
I don't think its bad at all. Personally I don't go to the field with less than a quart per acre, and 10gal of water per acre. That's right about 3oz/gal. Along with AMS and crop oil. Never had a problem with killing anything

I'd rather be strong than week. Week spray is for sure money wasted. I tailor my mix to the maturity of what I'm spraying. New grass, 1.5 oz. to a gallon of water. Mature, thick weeds w/Johnson grass or Dallisgrass, I use 2.5 to 3 oz. per gallon. In between, 2 oz. per gallon. That hasn't let me down yet. As far as time before discing, the same applies. I want the roots dead and decaying. It doesn't make much difference in the success of some plots, but small seeds especially, I'd rather have a really smooth seedbed.
 
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