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Brassica seeds and roundup
In August 2020 I took an acre of what had been a crop field and broadcast brassica seeds into it, sprayed with glyphosate and then cultipacked all in the same day. In fact I drove the sprayer to the field so that I could spray as soon as the last seed hit the field. No way anything could have germinated. I got almost no brassicas so I ended up over seeding with rye which saved the field and attracted a lot of deer. I thought that a drought may have cause the failed crop but I was at a loss.
This year I sprayed with glyphosate and then planted brassicas about 12 days later in four different areas. As I was finishing up the planting a neighbor texted that he had about 12 gallons of a glyphosate mixture in a tank with a wand he wanted to get rid of. I took the herbicide and touched up the fields where I had missed when I sprayed. Again all all of this happened in the same day. The brassicas look great right now except that the deer are browsing them. Every spot where I touched up with the glyphosate after planting there are no brassicas. I thought that glyphosate only impacted growing plants and had no impact on seeds. In fact I am afraid that I have passed that on to others on this site. However I am now convinced that when brassicas seeds are laying on top of the ground glyphosate will kill them. Has anyone had any experiences that either support or contradict?
It will not kill seeds or have any impact on anything that has not germinated. It kills only actively growing vegetation with no residual. What are the chances your neighbors tank was contaminated with something else?
I drilled a mixture of peas, beans, sunflowers, radish, WR, WW, and turnips the same day I sprayed on August 13th. We got one heavy rain then nothing but 90 degree temps for almost 3 weeks. Most of what germinated has since died from the lack of moisture. What didn’t die has been under intense bug pressure. I do have world class thistle though. I will be waiting for cooler weather and will drill winter rye with durana clover for next year. August plantings have not been kind to me 3 years in a row and now I have a thistle problem.
Can someone explain the iPhone formatting for bowsite? I put in tabs, spaces, and paragraphs. Regardless of how many spaces I put between paragraphs it comes out in this jumbled shit mess.
RIT, I can talk to my neighbor about it. I know that he said that it was just glyphosate, ammonium sulfate, dawn and water. I do not have a drill so the seeds are not covered by dirt. I prefer to spray after seeding so that I am not walking through herbicide. My beliefs were the same as yours and this year I have undeniable proof that what I sprayed killed the seed. The contrast is so complete.
Goyt………I did basically the same things as you on 3 different plots, on August 1st, other than I seeded into standing rye. I then rolled the standing rye flat with my cultimulcher, then sprayed with gly, all on the same day. We’ve had timely rains in August so everything sprouted and is growing well. I didn’t see any sign of the gly causing any problems at all. I’ve used a lot of gly over the years, and have never once had any type of residual issues when using it. My initial thought was the same as RIT’s, about the possibility of some residual herbicide left in the sprayer tank.
Here is one of the plots. My biggest problem was that the volunteer rye that came is super thick, and was suppressing the growth of the brassicas somewhat. I am trying something new this year. I sprayed those plots with clethodim to kill off any grasses and the sprouted rye, to hopefully give the brassicas less competition. A little difficult to see very well in the pic, but towards the back part of the plot, the rye wasn’t nearly as thick, and the brassicas show better growth than where the rye was super thick. Clethodim has little to no residual, so my thinking is that there is still a lot of volunteer rye on the ground that hasn’t sprouted yet, that will still germinate yet this year. Time will tell.
I’ve never spayed on top of planted seeds. What’s the point if you are doing everything the same day? Why take the chance it would kill your seed when it’s just a difference in the order you do things? Personally I spray, work things up and then plant. Everything is dead and I don’t have to worry about killing my seed. It’s not rocket science, why shoot yourself in the foot?
Lawnboytom…….first, let me preface this by saying I’m relatively new to the no-till plotting gig, however, I’ve been doing food plots for close to 25 years. IMO, the main reason to spray right after seeding/rolling is to kill the existing living weeds, without disturbing the soil, causing a new flush of weeds along with the new seeding. In my area, it’s getting more difficult to control weeds in fall plantings every year, so I’m willing to try different techniques to give me an advantage in controlling weed pressure. I’m also trying another new angle in a different brassicas planting. I sprayed Treflan on a plot that I had tilled a couple of weeks earlier, so it was pretty much bare dirt, (which is recommended for Treflan) I then incorporated the Treflan into the soil. Next, I broadcasted my brassicas, then cultipacked the entire plot. I’m curious to see what kind of weed control I get with this.
RIT and t-roy, you got my convinced that my neighbor probably add 2,4 D ester to the mixture that I got from him. We do that when spraying invasive species and he forgot or I misunderstood. Thanks for the help.
t-roy, here is a picture of a plot that had rye in. Once the critters started knocking it down and it was completely brown I mowed it. Right about July 30 I sprayed it and on August 14th I planted brassicas.
t-roy, here is a picture of the same plot last week. At first I thought that the brassica was coming in too thick but the deer have been thinning it. I do not seem to have any volunteer rye and the straw seems to be doing a good job of holding moisture. I put some fertilizer on it and I hope that it can get ahead of the deer browsing. There is a newly planted, high quality hay field 100 yards away so I am surprised that the deer are being so hard on the brassicas. The far side of the plot was planted in rye, crimson clover and radishes on 9/4 and the rye was already up 4 days later but it does not show up in the picture.
I think one of two things is happening. Something else is coincidentally killing your planting or there is another herbicide in the mix that is doing the dirty deed.
What flavor of glyphosate are you using ? I have seen several makers offer a mix of glyphosate and arsenal. Arsenal is soil mobile as well as taken up through the roots. It could be this or some other herbicide.
but the glyphosate is assuredly not doing it.
wish I had the time and acres to try some of that food plotting ! closest I get is putting some rye down on skidder trails and landings if there is an erosion issue.
Be careful what you wish for, blue spot! ;-) $$$$ JK— food plotting is very enjoyable. Thank you for your posts on herbicides. They are always informative.
Goyt….I’m surprised that you don’t have any volunteer rye coming up in your brassicas.
blue spot, he use a brand from Rural King I think with the only active ingredient being glyphosate but he could have added 2,4 D ester.
t-roy, for the first time last year I seeded a lot of rye in most anything I had. I was hoping to get some volunteers but not to the extent that you got. I rented some fields to a farmer for hay and he had a bad first cutting due to thistles so I let him cut and bail some of my clover and BTF plots before the rye went to seed. The rest of the plots had the rye go to seed. So far none of 4 brassica plots are showing any rye.
T-Roy, I am sure somewhere on the food plotting "package" there is a big warning that it is addictive and habit forming !!!!! I typed in the last response last night and never hit send so my comments were a bit stale. Goyt, Those deer are telling you 9 out of 10 of them prefer the baby brassica salad plate over the new grass sprouts ! I only ask about the formulation as I know Roundup comes in in an extended control formula with arsenal. It is a little more than just bud light with a slice of lime. I had to grab some county line glyphosate at tractor supply this summer and noticed they also have a extra strong version with a little arsenal in it. Thought there was a chance you may have inadvertently grabbed the wrong flavor.
blue spot, that is a good heads up. It is getting so one can not buy a herbicide without taking a careful look at the label. So many versions and the ingredients are not listed totally on places like Amazon.