Reviewing my knowledge of comfrey as a forage crop

Over the years of lurking in the permie world I have come across a lot of discussion of comfrey and its benefits.  I am about to do something, perhaps really dumb.  I am considering intentionally planting several acres of forage pasture in comfrey.  It is a big step, since it is so difficult to eradicate if it turns into a mistake.  I thought I would open this discussion to review my assumptions of the benefits of the plant; and ask for people's experience grazing comfrey on a large scale.

My understanding is:

It is a perennial crop that will withstand periodic cutting/grazing without killing the plant.

It is tolerant to low water input.

multiple species will readily browse the leaves without negative impact.

It is non invasive to surrounding properties through root growth or seed.

The above seem to make this a perfect forage component to a diverse pasture mix.  It seems so ideal I wonder why it has not been more widely utilized.  I feel there is a "gotcha" out there I am missing.

Has anyone planted for forage large areas with Bocking #4?  If so was it well received by livestock?  Does it have any allelopathic reactions with other plants?    In a mixed pasture with other forbs and grasses, are there any ill effects to livestock?

This planting will be a 40 acre silvopasture project with multi species rotational grazing including chickens, pigs, and cows.  Am I opening a Pandora's box of problems down the road?  I am okay with the comfrey being permanent, as long as I am not missing any negative effects to livestock.

I haven't planted it in a pasture area, but I have tried to plant large areas of Bocking #4 for feed and soil building. I'm in the southeastern US and have to say that I had a hard time getting it established, I think, because our summers tend to be too hot and droughty.

As far as feed, it's high in protein and calcium, and so good for dairy and pregnant animals. My goats love it. If it were in the pasture, they would probably eat it to death, unless it was protected by intensive grazing rotation to let it recover. As hay, it gets kind of crumbly, but I dry it and use it to top dress their feed.

Jack wrote "Reviewing my knowledge of comfrey as a forage crop

Terry: Reviewing my knowledge of comfrey as a forage crop.

LESS THAN ZERO. I had never even heard of it. So I look forward to hearing about it. Good for pastured pigs? Good things it has over other pasture plants? Down sides? Does it grow everywhere?

Here's a bit on its "medicine" uses.

https://www.healthline.com/health/what-is-comfrey#TOC_TITLE_HDR_1

Do any of these things make it unsafe for certain animals?

I have not tried a large area, but it doesn't survive without irrigation where I live and the wildlife loves eating it. I don't know what you deer pressure is, but they love it.

Stacy Witscher wrote:I have not tried a large area, but it doesn't survive without irrigation where I live and the wildlife loves eating it. I don't know what you deer pressure is, but they love it.

Funny how different it is in different places.  I never water my comfrey ever, hundreds of plants.  We have very heavy deer pressure, to the point I can't grow a tree without a fence for at least the first 3 or 4 years.  The deer never touch my comfrey.  We have elk as well and they don't eat it either.  

Trace - Location matters a lot. Our dry season is long and very hot, nothing much survives. Anything that is irrigated gets eaten to the ground. This time of year the deer eat everything including things that are deer resistant. They are bulking up before the winter. The two things that they don't eat are foxgloves and rosemary, but I doubt that they would make good forage for anything. I would suspect that the OP's climate is more like mine being in Texas but maybe they get some summer rain.

Since the OP is in Central Texas, he may very well have a problem with the deer eating a whole field of comfrey.

We planted a food plot of sunflowers for the quail and dove though instead, the deer ate the whole field overnight.

If the OP wanted to just plant a few plants I might suggest surrounding the bed with rosemary and french marigolds. This is not possible for a whole field.

I would love to grow some though I know it is just not possible where I live.  Folks only grow sheep and goats.

I appreciate all the shared knowledge.  Yes, summers are hot and dry, but we decent summer rainfall most years.  I am not worried about deer pressure.  If anything it will help keep them out of young trees.  I estimate I lose far more forage to grasshoppers than deer annually.  

Interesting that it may not establish well in dry conditions.  I will have to see what it does on my rain pattern.    I do have a feral hog population/problem, so spreading it across the pasture should be relatively easy once started.  I am not looking to make comfrey a primary species, although aware and okay with that possibility.  I am hoping it will fill a role in the 18" zone among Sunn Hemp, Velvet Bean, and Red River crabgrass as taller plants, allowing the clover, chicory, plantain and comfrey to pick up the abundant sunlight we have that filters through the taller grasses.

I have no experience with “bocking” but I have heard it is hard to establish from seed.

My experience is with the other one that starts from root cuttings and once established is difficult to eradicate, a 2 inch piece of root the diameter of a pencil is enough for it to regrow.  In dry times, it can dry to the ground, appears dead to the ground, but it’s only waiting.


My goats love it, but I would not plant solely comfrey as pasture.  I know deer can be a problem, and I despair planting pasture for goats where deer are numerous.  The neighbors say “oh, they don’t eat much, but I believe if I planted mixed forage pasture (alfalfa comfrey, chicory, daikon and so on) the deer would never even let it establish.  My next place is not going to be heavily populated with deer!

The things goats eat and deer don’t?  Hard to say!

A LGD kept deer out of my pasture in a prior situation, but I needed a fence to keep her in.  However, the fence to keep the dog in was a lot easier than a fence to keep the deer out.

That might be a solution for you 😊, just keep in mind the question of fencing the dog when you choose her, some breeds are jumpers.  (My current situation)

Good luck!

In the 1970 s we had goats and in mother earth news, organic farming  mag there were several articles on the use of comfrey. It was a popular topic. We began planting some plants to feed the goats more than for our consumption.  Then came reports, with proofs,of a person who feed large amounts to her goats and they developed liver problems. further info came in and It was confirmed that it caused liver damage. people seemed to settle for its use as a medicinal and in limited amounts as feed. There seemed to be agreement for its use as a stimulant in composting. That seemed to reduce or almost eliminate the articles that were praising comfrey as a superfood and popular fad food for man and beast.   We have many problems with deer as veggie predators in the interior of B.C.  I have learned that deer have food prejudices just as humans do. What deer eat here they wont eat elsewhere. There are whitetail and muledeer whose taste in food differs. It also depends on the time of year on what they prefer. A friend said to me a few days ago that back east in canada he had not heard of deer eating cedars and here it is deer candy. I try to be careful in making firm statements about things that seem to be true for me ,here that may not be so true elsewhere. I think that come with age. We were part of the back to the land movement in the mid 60 s and 70 s. It is too bad that the years of magazines and the wisdom they compiled are not available to those today.

In Alabama it will grow well only in partial shade. I love it for medicine but can’t get my rabbits to eat it at all.

My current "PLAN" for homegrown animal forage will take several years to mature enough to start animals. Comfrey is a part of that plan, and I've gotten both the Bocking 4 and Bocking 14 already growing on the property. But comfrey won't be the greater part of this plan. Hazel thinning's and mulberry trimmings will be included. I've not yet figured out how many plants/trees of each I'll need per animal (think goats, pigs, rabbits, fowl) but this is my initial plan.
Comfrey and mulberry are high protein leaves that can be dried into something of a "hay", or so I've read. Here in southern California we have alot of fruitless mulberry trees that get pollarded annually, and the pile of potential food from a single tree seems like it might be enough to get one goat through a couple weeks of eating! I have no current experience with hazel, but plan to have possibly over a dozen trees across the property. I'm thinking to use hazels and mulberry as a combination windbreak and food source for the goat pens when they come "home" for the night, and I'll look into other possible forage foods to supplement their "field" time.

From what I've learned about the many comfreys, those that set seed can be invasive. The Bocking types do NOT propagate by seed, but by root cuttings.  And because comfrey is a bioaccumulator plant with deep roots, the plants "mine" for the nutrients deep underground, storing them in the leaves and thereby making those nutrients available to other plants and animals.

One thing to be careful of is not providing a variety of feeds.  

I am planning to get mulberry and linden, maybe hazelnuts growing so that I can pollard, coppice, prune branches for my goats, but I worry about the lists of “toxic” plants I am not supposed to allow my goats to eat.

I have always relied on the idea that if they have plenty of choice on what to eat, they will not poison themselves, so I hang on to the principle of diversity in feeding my goats.

>> reports, with proofs,

>> further info came in and It was confirmed that it caused liver damage.

I have heard similar declarations for 20+ years.  I don't buy any of it.  I've wasted a lot of time looking for *something* substantive.  

Comfrey causes liver damage.
Rod Stewart had to get his stomach pumped.

I'm with Gary,

have never seen any reports or proof of liver damage in animals eating comfrey

My sheep eat it in varying amounts depending on what else they have access to.  In winter when they are on mostly hay they get very excited for some dried comfrey.

Our bunnies (n=2) love comfrey. The bumblebees love it too. I have it growing along my apple Belgian fence along with fennel, asparagus and alpine strawberry.

So field observations: 12 years ago a portion of the horse pasture was loaned out for a garden patch; Comfrey was planted on both sides as a root barrier.  On the orchard side it grows prolifically.  on the other side which is now just field it grows in the grass persistently but stunted when there is drought.  There are two stumps where poplar trees came up among them; comfrey next to those continues to flourish during drought conditions,  It produces during a zone 8 winter which allows it to spring back from a 4 month drought.  It seems to prefer a fungal dominated soil and association with tree roots. It can survive as a supplemental forage in a grass field often providing food for pollinators when other things are not available.  Root fragments can be easily be planted during rainy season by making a hole with a bar and dropping it in.  It has not really given me any problems only small benefits as I mow the field for mulch materials.

Here is what I know about the question of comfrey and liver toxicity: I took a class in herbal studies in the 90s and my teacher talked about that. Apparently there was a man who was very ill, he had liver failure he ate a lot of comfrey to try and cure the liver failure. When he died his death was attributed to comfrey rather than the pre-existing condition and the reason he was eating the comfrey.

Since that time every herbalist I know uses the root for topical purposes only because there are more alkaloids in the root, and use the leaves for tea or in their salads and green smoothies or whatever else without worry.

It’s funny how the medical field does that... A friend of mine‘s father had cancer. They caught it early. He went for treatment. The morning of his first chemo treatment he was a healthy man. Whether he died that afternoon or within the week I cannot remember but he died of the cancer treatment and his doctors wrote down cause of death cancer. So how much of the comfrey toxicity mythology comes from that one man who died I can’t say but my animals have eaten a lot of comfrey leaf and they’ve been fine. I have drank a lot of comfrey tea used a lot of comfrey topicals and I’m still fine.

We have no trouble growing comfrey here. We have about 300 plants that we started from cuttings we took from 2 plants we had in our previous yard. In some places, it would grow to over 4 feet tall, then topple over due to wind and its own weight. This spring, I put up a tall cylinder of fencing around the most vigorous plant in order to support and see how tall it would get. It stopped growing upward when it hit 6.5 feet but continued to flower and push out fresh leaves on the sides.

We built a new 4x30 foot bed for garlic and mulched it with comfrey harvested from about half of our plants. We occasionally bring comfrey leaves to our neighbour's chickens, and they eat it all, but usually after eating the clover and kitchen scraps we bring.

I live in Southwest Wisconsin.  Comfrey grows easily here and plants itself wherever it pleases.  It has many uses, but I offer one warning.  It is impossible to kill or remove.  Don't plant it anywhere you wouldn't want it forever.  I once needed to move a fruit tree that had comfrey growing next to it.  We built a 10-foot deep mound over the spot where the fruit tree had been.  Within a year, the comfrey was growing out of the top of the mound.

Kathy Crittenden wrote:We built a 10-foot deep mound over the spot where the fruit tree had been.  Within a year, the comfrey was growing out of the top of the mound.

Our old neighbour tried the opposite approach. They dug a deep pit where the plant was growing, disposing of any plant material they found, then had a large bonfire in the pit that they kept going for hours and hours. Guess what came back the next year.

Michael Helmersson wrote:

Kathy Crittenden wrote:We built a 10-foot deep mound over the spot where the fruit tree had been.  Within a year, the comfrey was growing out of the top of the mound.

Our old neighbour tried the opposite approach. They dug a deep pit where the plant was growing, disposing of any plant material they found, then had a large bonfire in the pit that they kept going for hours and hours. Guess what came back the next year.

good old comfrey! 😊 It would probably grow on Mars!

No really, I wonder if the mucilage in the roots both protects  and heals, AND keeps  the plant roots viable in dire conditions.  What comfrey survives is miraculous.  I am really glad I am my trying to kill any.

You can kill out comfrey! All you have to do is cover it with a 6 to 12 inches of old hay. I had it planted by a fence under a pine tree it was growing really well. UNTIL we started putting the round bales there and the loose hay was left over the spot. Two years later it still has not grown back.  I came here to read the benefits of it with horses and what it can treat. I have a horse that has eaten it all but the last two years every summer. I was considering moving it to where the animals have access to a few plants from spring to fall. Now I know I will be moving some of the plants in my garden to the pasture and paddock area.

Pandora Biskner wrote:You can kill out comfrey! All you have to do is cover it with a 6 to 12 inches of old hay. I had it planted by a fence under a pine tree it was growing really well. UNTIL we started putting the round bales there and the loose hay was left over the spot. Two years later it still has not grown back.  I came here to read the benefits of it with horses and what it can treat. I have a horse that has eaten it all but the last two years every summer. I was considering moving it to where the animals have access to a few plants from spring to fall. Now I know I will be moving some of the plants in my garden to the pasture and paddock area.

I think it depends very much where you live and how healthy your comfrey is.  I have had it grow up easily through 6 inches of wood chips.  Loose hay would seem to be much easier for it to grow through.  I have only been able to kill it but covering the area with black rubber roofing material and leaving it in place for a year or so.

Important to know about comfrey:  there are two kinds, one makes seeds and one doesn’t.  Some people complain that comfrey takes over…. That’s most likely from seeding.

When I started growing comfrey you could only get it from a friend.  That is still the kind I grow.

Goats eat it in large amounts.  I can’t speak for other animals.

There are so many varieties of comfrey. I planted a small creeping one next to a chicken coop, i thought they would eat it to death, but it's still holding out while the chickens seem to nibble it , but no killing.
On the toxicity i heard the animal experiments were done on horses getting only comfrey, then dying and giving comfrey a bad rep. Still, it does have toxins in it which are bad for the liver, so why not compost it and grow food good for us with it and use the root for balms and compresses. I drove over my gf's dog foot, it was limping, i dug out a root, machined it into a paste, she applied it, putting a bandage on, next day it was like nothing happened.

I know nothing about the horses dying. I have heard a story that I think is true. A man was very ill and he ate a lot of comfrey hoping to heal himself. I think it was a liver condition. I think the representative of the medical profession had offered no hope. He died. That death was attributed to the Comfrey. Kind of like if someone dies of cancer treatment, they call that a cancer death not a treatment death.  After this event comfrey was not available in health food stores for a few years.

What I believe is true about the toxicity of Comfrey is that it contains alkaloids that are toxic. There are more of alkaloids in the root than in the leaf.  And so I have always been cautioned to eat leaf, but not the root. I had goats who ate huge comfrey plants. My belief about goats is that despite the long lists of plants that Goats should not eat because they are toxic to goats, that if they have adequate feed available, the goats will not poison themselves.

I think the original post proposes a very diverse mixed pasture, which the animals will be rotated through. I think that is entirely safe and healthy for grazing animals.