My Cover Crop Plot - What Went Wrong This Year?

farmlegend

5 year old buck +
Southern Michigan. In late May, I had my trusted contractor drill in my diverse cover crop mix on the nine acres of my cover crop ground. This project is in Year 4.

This was the first time I planted without a total burndown, as I want to gradually reduce herbicide use. I did spray one pint per acre clethodim plus some crop oil about a week before planting, as my primary competition concern was coolseason grasses(this turned out to be effective, as CSG’s are not a problem at this point). There was a good amount of 2" fledgling marestail out there, but I was hopeful the competition from my seed mix would crowd it out. There was also a fair amount of medium red clover around, carrying over from previous years.

The seed was drilled in at a depth of 1”. The mix included spring oats, cowpeas, Japanese Millet, chickpea, grain sorghum, buckwheat, balansa clover, African cabbage, fenugreek, PT turnip, endure chicory, and a few other seeds.

Growing conditions have been excellent.

The marestail is kicking butt, and is everywhere, as is the red clover, which is drawing the deer in reliably. But almost none of the cover crop I planted showed up at all, other than a very small smattering of sorghum, buckwheat, and chicory. Absolutely no appearance from the oats, which was the most abundant seed in the mix by weight, or the Jap millet, which usually kicks ass, and that is utterly mystifying to me. There is a substantial presence of Boston Plantain, which I had frostseeded in March, in the plot. At this point, I'm chalking it up as an expensive failure, and not my first one in 26 seasons of foodplotting.

I’ve seldom felt so stumped. Thinking there’s some sort of weird allelopathic activity going on, with either the marestail or red clover chemically suppressing everything else. Or perhaps the seed was drilled in at a depth far greater than an inch. Had I to do it over again, I would have toasted the plot with Liberty like I did last year.

At this point, with the future in mind, I want to stoke biomass for the future. I plan on broadcasting a boatload of cereal rye upon it next month, along with some hairy vetch, YBSC, and whatever other small seeds I’ve got in the barn.

Any thoughts?







Addendum: I broadcast a good deal of winter rye and wheat on most of this plot last fall. Apparently, the rye has some allelopathic qualities, and killing off the cereal grains was part of the reason I sprayed the plot with clethodim before planting. From the alseed site:

#8 Allelopathy
Associated cover crop species: Rye, wheat, brassicas, sorghum
Allelopathic compounds are water soluble compounds released into the soil by certain cover crop species (for example, winter rye and to a lesser extent other small grains, brassicas, sorghums and millets) that suppress the germination of small-seeded species. That can be a desirable characteristic of cover crops if your goal is weed control but allelopathic compounds can also suppress cash crops as well.

The degree of allelopathic activity varies from species to species, but it has also been found to vary among rye varieties. Here are general considerations regarding allelopathic compounds:

  • Highest concentration in young, green winter rye early in the spring
  • Leached from roots and to a lesser degree from top growth
  • Water soluble and released rapidly into the soil when cover crops are tilled. Less so if cover crops are chemically terminated
  • Greatest impact on small-seeded species. Large-seeded corn, soybeans, and sunflowers are less affected.

Solution​

Avoid using cover crops with allelopathic properties in rotation before planting small seeded crops, such as alfalfa, clover and other forage species. Medium-sized seeded crops may also be affected, such as flax.
 
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Southern Michigan. In late May, I had my trusted contractor drill in my diverse cover crop mix on the nine acres of my cover crop ground. This project is in Year 4.

This was the first time I planted without a total burndown, as I want to gradually reduce herbicide use. I did spray one pint per acre clethodim plus some crop oil about a week before planting, as my primary competition concern was coolseason grasses(this turned out to be effective, as CSG’s are not a problem at this point). There was a good amount of 2" fledgling marestail out there, but I was hopeful the competition from my seed mix would crowd it out. There was also a fair amount of medium red clover around, carrying over from previous years.

The seed was drilled in at a depth of 1”. The mix included spring oats, cowpeas, Japanese Millet, chickpea, grain sorghum, buckwheat, balansa clover, African cabbage, fenugreek, PT turnip, endure chicory, and a few other seeds.

Growing conditions have been excellent.

The marestail is kicking butt, and is everywhere, as is the red clover, which is drawing the deer in reliably. But almost none of the cover crop I planted showed up at all, other than a very small smattering of sorghum, buckwheat, and chicory. Absolutely no appearance from the oats, which was the most abundant seed in the mix by weight, or the Jap millet, which usually kicks ass, and that is utterly mystifying to me. There is a substantial presence of Boston Plantain, which I had frostseeded in March, in the plot. At this point, I'm chalking it up as an expensive failure, and not my first one in 26 seasons of foodplotting.

I’ve seldom felt so stumped. Thinking there’s some sort of weird allelopathic activity going on, with either the marestail or red clover chemically suppressing everything else. Or perhaps the seed was drilled in at a depth far greater than an inch. Had I to do it over again, I would have toasted the plot with Liberty like I did last year.

At this point, with the future in mind, I want to stoke biomass for the future. I plan on broadcasting a boatload of cereal rye upon it next month, along with some hairy vetch, YBSC, and whatever other small seeds I’ve got in the barn.

Any thoughts?







Addendum: I broadcast a good deal of winter rye and wheat on most of this plot last fall. Apparently, the rye has some allelopathic qualities, and killing off the cereal grains was part of the reason I sprayed the plot with clethodim before planting. From the alseed site:

#8 Allelopathy
Associated cover crop species: Rye, wheat, brassicas, sorghum
Allelopathic compounds are water soluble compounds released into the soil by certain cover crop species (for example, winter rye and to a lesser extent other small grains, brassicas, sorghums and millets) that suppress the germination of small-seeded species. That can be a desirable characteristic of cover crops if your goal is weed control but allelopathic compounds can also suppress cash crops as well.

The degree of allelopathic activity varies from species to species, but it has also been found to vary among rye varieties. Here are general considerations regarding allelopathic compounds:

  • Highest concentration in young, green winter rye early in the spring
  • Leached from roots and to a lesser degree from top growth
  • Water soluble and released rapidly into the soil when cover crops are tilled. Less so if cover crops are chemically terminated
  • Greatest impact on small-seeded species. Large-seeded corn, soybeans, and sunflowers are less affected.

Solution​

Avoid using cover crops with allelopathic properties in rotation before planting small seeded crops, such as alfalfa, clover and other forage species. Medium-sized seeded crops may also be affected, such as flax.
I gotta fevuh.....

The only prescription....

.......more gypsum


bill
 
Sounds like a combination of:

Cleth took out your oats, millet, and sorghum
Seed depth took out all your small seeds
Browse took out your peas and buckwheat

Just a guess. Did it all go through the big hopper, or did the small seeds go through the little hopper?
 
Sounds like a combination of:

Cleth took out your oats, millet, and sorghum
Seed depth took out all your small seeds
Browse took out your peas and buckwheat

Just a guess. Did it all go through the big hopper, or did the small seeds go through the little hopper?
I’m thinking the clethodim did it.

And all of the seeds went through the big hopper. Small seeds probably too deep and seeded too heavily. He did run out of seed sooner than calculated and had to substitute some of his own proprietary mix.

Need my own drill so I can employ two seed boxes. Perhaps for next season.
 
Legend curious how much rye per acre you will be broadcasting and when in August are you planning to do this. I live near kazoo.
 
Legend curious how much rye per acre you will be broadcasting and when in August are you planning to do this. I live near kazoo.
Well, I bought 20 56# bags. As to timing, probably 8/9-10 or so. Have some other stuff I’ll be dumping along with it - some daikon radish, crimson clover, YBSC, hairy and crown vetch, endure chicory, and whatever else is laying around the barn.

Shooting for “just before a good rain” LOL. I’ve always hated that stupid line.
 
Legend curious on how many acres your planting with the 20 bushels.
 
Clethodim does have a residual effect in the soil. I learned this the hard way when I converted a couple of switchgrass plots back into food plots. Sprayed one last time with Clethodim to get a good nuke on the switchgrass and then drilled a fall mix. Broadleaf plants came up fine but no cereal grains. Live and Learn.

I always drill small seed from the small seed box where it stays up topside when it spills out of the small tubes.
 
Clethodim does have a residual effect in the soil. I learned this the hard way when I converted a couple of switchgrass plots back into food plots. Sprayed one last time with Clethodim to get a good nuke on the switchgrass and then drilled a fall mix. Broadleaf plants came up fine but no cereal grains. Live and Learn.

I always drill small seed from the small seed box where it stays up topside when it spills out of the small tubes.
The expensive lessons tend to be the ones you don’t forget.😉

This one wasn’t cheap, as I hired out the planting and paid good dough for a custom seed mix.

What’s in the plot now is marestail, red clover. and an astonishing amount of boston plantain. YBSC is coming on in places, and there’s a smattering of small burnet and endure chicory. Along with this fall’s broadcast, and a March frostseeding of some sort, I’m planning on letting ‘er rip perennial style in 2026, hopefully packing on some biomass.
 
The expensive lessons tend to be the ones you don’t forget.😉

This one wasn’t cheap, as I hired out the planting and paid good dough for a custom seed mix.

What’s in the plot now is marestail, red clover. and an astonishing amount of boston plantain. YBSC is coming on in places, and there’s a smattering of small burnet and endure chicory. Along with this fall’s broadcast, and a March frostseeding of some sort, I’m planning on letting ‘er rip perennial style in 2026, hopefully packing on some biomass.

That new drill you've been thinking about is looking better all the time, I'll bet. Mine is now 10 years old but it is still like new and I am sure it is worth a lot more today than what I paid for it then.... Not to mention that it has saved me many hours of tractor seat time over the years. There is also something to be said about the adage that goes...."If you want it done right....do it yourself".

Of course, there is a learning curve to a lot of this stuff and lessons about herbicide application and plant back intervals can be costly.
IMG_8771.jpeg
 
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That new drill you've been thinking about it looking better all the time, I'll bet. Mine is now 10 years old but it is still like new and I am sure it is worth a lot more today than what I paid for it then.... Not to mention that it has saved me many hours of tractor seat time over the years. There is also something to be said about the adage that goes...."If you want it done right....do it yourself".

Of course, there is a learning curve to a lot of this stuff and lessons about herbicide application and plant back intervals can be costly.
View attachment 81042
Yeah, I should have bought one like yours last year, when there were a few nice used ones on the market in the high teens within a reasonable distance, but I wasn’t quite ready. Nowadays, no used 606NT’s out there and the dealers are firm on their pricing at nearly 30k. If nothing shows up I may have to swallow hard and write the check next year.
 
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