Help with weeds

[Nova]

I have posted about this plot before and have narrowed my plan down to 2 options. The plot is 4 acres and I rotate corn and beans in it. I've been struggling with pigweed and both ragweed and giant ragweed in the plot. Which of the follwoing options do you think are best for next year.

OPTION #1
Till the plot under in the spring,wait about 3-4 weeks for weeds to germinate, spray with 2-4D or 2-4 D Gly mix. Wait another 3-4 weeks and till again to bring weed seeds to the top and let them germinate. Wait another 3-4 weeks and spray again with 2-4D or 2-4D gly mix. About mid August till and plant the whole thing in winter rye seeded heavy. Then the following spring plant beans or corn no till once the rye gets about 12-14" tall roll and spray with gly.

Option #2
Till in spring and plant corn. Then before corn gets 6" tall spray with 2-4D Gly mix and hope the residual from the 2-4D can keep the weeds at bay until the corn can shade them out. The good in this one is I don't have to let the plot sit for a year with nothing in it until fall, the bad is that I don't get as good of weed control without having several sprayings on young weeds that germinate later in the year.

Both options will help to terminate ragweed and pigweed which is the number one goal for this upcoming year. I really don't want to switch to anything with dicamba herbicide. I've read too much negative about it. Mostly that is it very volatile and spray drift is a major concern. I'm not at the farm all the time to spray when conditions are absolutely perfect.

 

[trampledbyturtles]

Like option one,
but would consider doing it for 2 seasons in a row if it is a seriously bad problem. Pigweed is nasty stuff an can release alot of seed once it allowed to set seed, an some of it is predisposed to delay germination for some time.

Option 2 would be to find better pre-emerge chemicals. Know you can stack a few of them, one prior to emergence then another before corn reaches 11-18in

Or do a combo of option 1 for 1 yr, then follow up with a better chem program the next.

 

[S.T.Fanatic]

I'd consider planting the shortest day corn you can and planting late after multiple tillage passes. We have a fair amount of organic farmers in my area and rag weed seems to be their biggest problem. My input is based off of how they do it. Later in the spring the soil is warmer anyway and the corn will grow at a faster rate.

 

[S.T.Fanatic]

You may also be well advised to frost seed some crimson clover to help compete with the weeds and add a few N credits.

 

[Tree Spud]

I like #1 also. The latent seed issue always is a problem and soil disturbance helps to uncover them. One suggestion to speed the process up would be to eliminate the 1st till and just spray what greens up first thing in the spring. After about a week, then till and wait for the second weed emergence and spray.

To help with weed control I always over seed in early Sept with winter rye. It is alleopathic which can suppress weed & grass growth.

 

[BuckSutherland]

I farm in McLeod county. Some of the earliest know resistance to glyphosate started right where I farm. First was giant rag, and now waterhemp/pig weed has come on strong. The best way to combat resistant weeds is to never let them germinate. That means pre-emerge chemicals.


If you want soybeans you should solid seed them early, then get a kick ass pre emerge like 5 oz/acre of authority first down. It will keep the ragweed and waterhemp from germinating for about 3-4 weeks depending on rainfall. You spray this right over the top immediately after planting. It acts like a blanket against weeds. Then just as the weeds start to germinate you go out and spray something like warrant ultra, which is flexstart GT and warrant. The flexstar takes the existing weeds out only if they are small, and the warrant will give you another blanket against letting the weeds germinate again. By then you should have canopy. Then around the first week of August you should be able to broadcast your rye and plant corn next year.

24d and glyphosate are pretty worthless. Too much tillage and you turn your soil to shit.



2 years in a row I have the highest yielding plot in MN, SD, WI, ND, and most of IA for Asgrow soybeans (#1 selling bean in the country).

These are dicamba beans that were sprayed without any xtendimax. My program was:

4.5 oz authority first pre
full rate of warrant ultra post + 4 extra pts of warrant.

Fields were pretty clean for the most part, except the edges. Those are 80 bushel beans in the picture.

 

[Nova]

To help with weed control I always over seed in early Sept with winter rye. It is alleopathic which can suppress weed & grass growth.

Option #1 has fall planted winter rye for that very reason, but I have better luck planting it mid August at our farm.

 

[Barndog56]

For a completely different perspective........

Pigweed and ragweed aren't the problem with your plot, they are just symptoms of your problem. The problem is that carrying out the conventional ag practices of heavy tillage and pesticide and fertilizer usage has turned your soil into dirt. The bacteria/fungi balance of your plot has been swung way over to the bacteria side, which benefits pigweed, ragweed, and other weeds. No matter how many times you till and spray, these or other weeds will return as long as your dirt is dominated by bacteria.

The solution is turning your dirt back into soil. You've got to add organic matter and fungal life to your plot. What you need is compost, most likely on the order of 2 or 3 tons per acre. The fungal life in good compost well regenerate your soil, bring the bacteria/fungi ratio into a better balance, and unlock the nutrients your desired crop needs, so your plot will no longer be the perfect environment for pigweed and ragweed.

I know most people are reluctant to switch to something completely different. Perhaps test it out on just 1/2 acre.

For a full explanation, look for a video called "The Roots of Your Profits" with Dr. Elaine Ingham, on youtube.

 

[BuckSutherland]

That is a pretty big pantload Barndog. Maybe in a perfect world that line of thinking works. If I did everything you said what would stop the neighbors neighbors waterhemp seed from blowing all over my field and filling the seed bank right back up? This stuff has an amazing ability to travel and spread quickly.


Also, I have some ground that is fully manured with bedded pen pack from beef cattle. Most of that ground has had 30+ tons of manure applied in the last 5 years. I have raised the organic matter almost 2 full pts in 8 years. I started at about 4, and now its close to 6. If I let it go it would be FULL of waterhemp and giant ragweed in 30 days. I do less tillage than anyone around. Mostly just one pass in the fall with a Glencoe soil saver chisel plow, then level it with one pass in the spring with the field cultivator and I plant. I dont even touch my bean stubble in the fall unless I rut it up with the combine.


There is no magic bullet for weeds.

 

[Tree Spud]

One other key carrier of weed & grass seed are the deer them selves. As they walk through grasses & weeds, their fur will collect and moved elsewhere.

 

[buckdeer1]

Marestail is almost as bad as pigweed to try and kill,I am using pre emergent this year,this is probably the only way to attempt to get a handle on the weed seed issue

 

[Mortenson]

Anyone have thoughts on the best pre's for brassica plots? Total burndowns aren't getting the job done any longer, on my plots specifically, which are 100% no-till and done with cover crops like red clover and cereal rye.

24d isn't very effective on pigweeds around here these days, but I find it's still death on Giant rags. Feels good to see them hanging their heads by the next day.

Overlapping good pre's and using different modes is definitely the way to battle the super weeds, IMO. Never let them emerge. And if they do, kill them tiny.

 

[MickT]

I don’t know if any preemergence herbicides labeled for use in brassicas. Sounds like it’s time for a crop rotation to change things up.


Sent from my iPhone using Tapatalk

 

[buckdeer1]

I don't plant brassicas anymore but usually pigweed is already dormant if you are planting only brassicas you could spray them or keep mowed until planting

 

[Jake]

Same boat as you Nova. Smaller plots though.

My one bad pigweed 1/4 acre plot 2018 recap:
Frost seeded clover(buck on bag mixes) heavy. Mowed often and hit it with 24db early on and once end of summer. Last 24db dose came a dry spell after and every looked toasted.. Broadcasted winter rye into it and clover bounced back with some rye. Looked great and no pigweed to be found.

Iola plot. Frost seeded heavy and no pigweed in sight.
Killed off a strip and then tilled and planted brassicas and low and behold pigweed came back to visit.

 

[Nova]

I decided to go with the till it up a couple times, then burn it down before planting rye in August. I tilled it up in May when I did my other plots. Just went back up this weekend to spray the other plots and boy am I glad I did what I did with this one. It looked like someone drilled ragweed seed into this field there was such consistent and vast plants. There was some pretty good patches of pigweed too, but the entire field was covered in ragweed plants. Hitting this with gly would have been a complete waste of time and money, but hitting it with the tiller got me 100% termination. Now let them reseed and hit it with 2-4D and gly in Mid July before a mid August rye planting. Follow that up next year with no till beans planted right into the rye, roll the rye and spray with gly.

 

[Jake]

Sounds like a solid plan. Thanks for the update.

 

[BuckSutherland]

This plot will be full of waterhemp in a few weeks, especially if we get rain. Tillers destroy soil, organic matter, pore space, and just bring up the next crop of weeds. You could have planted Enlist beans for $50/acre, sprayed it with authority first for about $20/ac and had next to zero weeds emerge, then spray it with 24d, roundup and warrant about 5 weeks later and the plot would have been 100% clean. Could have still put your rye in August. You need residual chemicals to never let the shit germinate, and hit your escapes when they are SMALL.

 

[S.T.Fanatic]

You forgot to mention compaction.

 

[Nova]

Got back to the farm to see the pigweed took it's turn germinating. In a month it was 1-2' tall. I hit it hard with chemical as you can see it starting to wilt. Mid August I'll go up and till it up again and plant winter rye. This summer should have gotten a lot of the seed bank knocked down if nothing else.