Thursday, May 23, 2024


004 (2)You’re probably looking at my title and thinking that I spelled in error, the act of slumber after a heavy lunch. In my defense, naptime is usually when I think about how to react to all the purple knapweed growing on my farm this year. Just as I enjoyed an intense drool, dreaming of endless pristine pastures devoid of unsightly weeds, the annoying alarm clock of Mother Nature goes off and brings me back to the reality—weeds(also known as forage) are here to stay!

Poet, Phillip Pulfrey said it best:

I learn more about God
From weeds than from roses;
Resilience springing 
Through the smallest chink of hope
In the absolute of concrete….

My intimate relationship with this forage-weed is a lot like a marriage, it takes patience and compromise to work. Many folks abhor this matrimony and seek divorce by lethal injection with chemicals. I’m too darn stubborn to take this easy, costly route for I have an appreciation or affliction in working with this plant as a symbol of diversity and importance. In my way of thinking, God gave us this plant for a reason and I’m determined to find out why.

According to the late Newman Turner, this “herb” knapweed or hardheads, as he called them, is one of the few indicators of phosphate deficiency. He said, “The existence of knapweed is one of the few justifications for applying rock phosphate as well as manure and ground limestone.” Curious to me was his description of how far down the plant’s roots will go to tap subsoil phosphorus and thrive when other plants won’t. Since I have low phosphorus on many fields because of no grain importation or added soil amendments, this makes sense to me.

Ok, so it’s evident I have a problem. In addition to fertility, I have out-wintered on fields, scarring them up and compacting them which gives way to plants that can fill the void and have rolled out bales with knapweed plants in them. My friend Nathan also thinks the severe drought with long pasture recovery periods and the die back of other pasture species from last year is helping with the proliferation problem. I’m sure it’s a combination of many factors.

knapweed after grazing
Grazed Knapweed in the Bishopp pastures

The bigger question is what to do or not do against our holistic farm goals which direct us to like diversity, soil biology, water quality and wildlife. Can bigger picture thinking and land management be the right tools? I’m convinced if you study and observe the subtleties of nature, you’ll find the solution.

If you can accept the spotted, Russian or whatever knapweed species you have will always be around in some fashion depending on conditions, I think you can move forward in controlling the forage plant. Ian Mitchell-Innes coaxed me to move towards what I want by planning my grazing. He also liked that we have the most overlooked weed killer, frost and snow. I took this knowledge to heart.

LinktoSKArticleHere are a few control measures, minus chemical or biological remedies; I have tried with some success:

1) Teach your animals to eat it by learning animal behavior from Kathy Voth’s training regime.

2) Plan to graze an infested field when the plants are young and tender(4-6”) while getting enough animal impact to eat every plant or trample them.

3) Manure heavily or add compost or soil amendments so other plants out compete the weeds.

4) Graze more frequently avoiding long recovery periods >40 days and clip after each grazing period.

5) If the knapweed gets ahead of you, have the patience to let it flower (allowing bees to make you some awesome honey and grassland birds to nest) and then turn animals in to eat the blossoms and top leaves thereby stealing the plants ability to seed.

It’s number 5 that has me most interested. I’m not too old to forget the Bambi movie when Thumper the bunny rabbit was scolded by his mom for just eating the blossoms and came up with this famous quote, “Eating greens is a special treat, it makes long ears and great big feet. But it sure is awful stuff to eat.”

Here's the analysis of Knapweed as a forage. Click for a larger view.
Here’s the analysis of Knapweed as a forage. Click for a larger view.

After witnessing the cows eating all the purple flowers and the top leaves when turned into a paddock, I decided to do a brix test on the plant. Turns out Thumper was right, the brix was twice that of the other plants in the field. I took it even further. I harvested them and sent them into the Dairy One Forage Lab. The technicians must have been scratching their heads as they tested them. In Jerry Brunetti’s honor, the sample (attached) came back indicating the plant parts were as good as pre-bud alfalfa with an excellent mineral profile. This was good stuff! Why would we want to kill it?

With the plant tops bitten off here in July and August, I went ahead and clipped the paddocks down so I would have quality stockpiled forage for fall and winter grazing before our frost in the first part of October. Taking a cue from Newman Turner’s chapter on making an herbal ley with a mower this now awesome forage-weed that sucked up phosphorus from the subsoil is chopped up and returned back to the soil biology to fertilize the growing sward. Cycle complete!

knapweed blossom eating before and after
Knapweed pasture, before and after grazing.

My long view of this purple knapweed problem and solution manifested itself while I was lingering in a field filled with busy pollinators. How would my decision effect more than me as the workers of humanity harvested pollen? Shouldn’t we weigh the control options very carefully because we have the ability to think with this big brain cell of ours?

I’m convinced if you work with nature on the same plane, you’ll find the answers you need. But it might take alittle nap to get you prepared for a change in mindset.

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Troy Bishopp
Troy Bishopp
Troy Bishopp, aka “The Grass Whisperer” is a seasoned grazier and grasslands advocate who owns, manages and linger-grazes at Bishopp Family Farm in Deansboro, NY with his understanding wife, daughters, grandchildren and parents. Their certified organic custom grazing operation raise dairy heifers, grass-finished beef and backgrounds feeder cattle on 180 acres of owned and leased pastures. Troy also mentors farmers on holistic land management for the Madison County Soil and Water Conservation District and the Upper Susquehanna Coalition as their regional grazing specialist. This award-winning free-lance writer, essayist and photographer maintains a website presence at


  1. Wanted to say thanks for this article. A few years ago after watching the video 12 Aprils ( I started learning (didn’t know what a no till drill was, I’m a computer guy with a few acres of irrigated pasture and a wife that grew up with 4-H). I learned about no till/sustainable agriculture ( learned about strip grazing and mob grazing ( learned about the importance of soil coverage (
    After watching the a video on intensive grazing I realized I needed to stop my animals from going back to an area recently grazed ( And my life has changed.
    I started a moving slot in my electric fence, I only have a few acres. Last summer when moving the fence through an area infested with the despised Knap Weed I noticed that was the first thing the cows went for. They even went past alfalfa and clover blooms to get to the flowers on the knap weed. I was dumb founded. Knapp weed is considered an intrusive weed and I have neighbors ‘helping me’ by spraying it. I didn’t want spray around my animals (felt guilty for getting after my father in-law, we’re supposed to respect our elders) even if it was between the fence and the road. I asked him not to spray I will come out an pull it by hand.

    I also have butter cup that is considered a weed by my neighbors. My thought is if my 2 cows, calve, and 5 goats will eat it and not hurt them it is not a weed it’s food. I learned the butter cup is not bad for the animals till it flowers and I learned it is a sign your soil is to wet and or needs fertility. It was exciting for me to learn about the phosphorus side of the knap weed. if you watch Trantham 12 Aprils he did a plant test on the top part of the plant that his cows broke out to eat and found how much more digestible the top third is. As he said this isn’t rocket science it learning from watching even from what you thought was a mistake “university of farmer Tom”

    Some bullet points I keep hearing, I’m harvesting sun, increased organic material equals better soil.

    I’ve concluded I need to leave some grass (weeds) to grow and catch the sun when the animals are done grazing, and if it grows and does not hurt my animals then it is helping me by putting organic material down. I’d love to let the knap weed grow but Idaho has it listed as a noxious weed so I’m supposed to control it. But I sure don’t want to use poisons. Again just wanted to say thanks for your article helps me know I’m on the right path. – Stein

  2. My Dexter cows eat all the flowers on Canada thistles in their pastures. They eat some of the early “soft” greens. The bull sometimes eats cut and wilted thistles. My problem is getting rid of the roots.

  3. I enjoyed the piece better the 2nd time because I’ve been able to see some result. This year’s batch of CAFO dairy heifers are actually eating the buds, flowers and the top leaves better than the seasoned heifers. New food=trying more? It may be the heifers needed more minerals that was in the knapweed too. Still struggling with balancing too much rest that favors these kind of plants. Still excited about the pollinator aspect of timing the knapweed flowers and grazing/clipping. Thanks for the comments James and Kathy

  4. Troy,

    We have also been working hard on getting our spotted knapweed grazed off as it moves from bud to full bloom. I have been very impressed with how well this set of heifers is eating it even at it progresses to full bloom. This is one of those rare situation where I have been moving the cattle twice and sometime thrice a day to encourage them to eat even more.


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