Author Archives: Linda Winfield Cowles

Managing Thin Soles

So much about thin soles is the trim, providing adequate sole protection while sole develops and getting the nutrition right…

What Is “Normal”???

When you start discussing thin soles, you need to remember that sole thickness varies widely based on age, breed, hoof care history, diet – everything is relative!

According to several vet friends, most “normal” horses have thin soles… 10mm is supposed to be average, but  6-8mm may be more “normal”.

Normal for most horses is quite thin relative to a mustang on soft range! Thick soles like we see in some walking horses and mustangs are not normal for most breeds or horses, and exceptions even exist in the gaited horse breeds… sole thickness varies widely, period.

Thick Sole Isn’t Always Good

I have been able to get a very thick sole to accumulate using Epona synthetic shoes, but it sheds back to “normal” once the horse is left barefoot. My friend Asa, in Las Vegas, hates thick sole because in her arid region, it needs to me trimmed out.

Too much of a good thing is a bad thing.

Rehabbing A Thin Sole?

If a horse has a sole that isn’t worn or trimmed to be thin,  and you leave a more stout wall &/or protect the sole from wear, then feed a better diet (see ! ) and use something like Keratex or Hoof Armor, you may be able to add 1 to 4 mm. Maybe!

In a case where the sole is already a a relatively healthy depth, and the wall height is good, you may not be able to get much improvement.

If a horse has worn his sole thin because his walls have been trimmed or worn short, like most of the thin soled horses I see,  or if the sole has been thinned in the trimming process, you can almost always get more sole to accumulate by tweaking the trim, diet and protection. Here’s my checklist:

  • balance the minerals
  • Feed straight grass hay (take away alfalfa and oat)
  • boot 24×7 or glue on synthetic shoes or boot shells
  • add boots for all exercise if left barefoot
  • change the environment to be non abrasive ; add soft dirt, saw dust, move to a soft pasture
  • change the trim technique to NOT trim sole and to let the walls get to be 1/8 to 1/4″ beyond the sole
  • Try Keratex applied daily.  “Keratex Hoof Hardener is a gentle acting chemical formulation which forms additional intermolecular bonds between molecules of keratin through the process of cross-linking. Keratin is the main protein constituent of horn and is best described as the building block of the horn structure.”
  • Try Hoof Armor “Hoof Armor® hoof protection is an easily applied adhesive coating that Farriers and horse owners alike can utilize to protect their barefoot horse’s hooves against abrasion and wear.”


Again, what is normal for one breed or individual, like a typical Gaited horse or Morgan, would be very thick for a TB or some lines of QH. Sole depth varies. My Marcel, a never shod Arab, has TB type feet, a thinner sole that often needs more protection.

 Should You Worry?

I only worry when the horse is uncomfortable in its living environment.

I used Hoof Armor and glue-on Glove shells on Diana Thompsons Timothy, a 29 to 32YO TB with historically thin soles, typically 6mm, and the result was that after 3 years barefoot, he had 12 to 14mm of sole depth. So sometimes it can happen but it really depends on the individual case.

In Tim’s case, we changed his diet and used glue-on boots for 6 months to protect his soles, and when they came off I used the Hoof Armor. He was on a super abrasive surface, so his feet wore down fast and we’d put him back in glue-ons after 5 to 8 weeks. If he’d been on a normal footing they might have stayed good longer… I don’t know.

Best goals are to try to get the horse optimally comfortable, keep the sole from wearing too fast…

Important To Remember:

  • Alfalfa often results in a more brittle wall and poor wall attachment. I see this on most horses…  the feet almost always get better when alfalfa is removed. Many horses grow a soft wall on oat or grain hay. I don’t know why! Its anecdotal.
  • I was skeptical about how much the small amount of alfalfa in the Elk Grove Stable Mix could affect the feet, but have one client who exchanged Elk Grove for straight grass hay pellets and the difference in the amount of wall separation by the next trim was significant. Its anecdotal, but its something you can try.
  • Too short a wall trim eliminates traction so the sole is subject to more abrasion.
  • Temporarily letting the heel get a bit taller helps relieve sole abrasion. Let the sole grow and you can lower the heel later.
  • Using boots 24×7 for a week to 2 or 3 months (with pads and Gold Bond) protects the sole and allows it to accumulate. Once the walls are solid and sole has developed, feet usually stay nice unless the environment is extremely abrasive.
  • Thin soles make feet tender and can result in mild inflammation, which appears to cause poor wall attachment and wall flare… vicious cycle! Wall attachment is better when feet are comfortable.


I trimmed a horse yesterday (large WB type, 1200 lbs) that I have been trimming for 5 months. The prior trimmer was trimming her extremely short, and I expected her to have nice feet in 6 weeks, so I was puzzled. The owner swore she was on straight grass hay diet. Everything else in the diet was perfect,but the mare had persistent stretched white line and I felt she was getting alfalfa! Trusted the owner but… gut feeling…. the wall was smashed flat at the base, and the sole was thin and flat.

I’m impatient. I was wondering if mild solar inflammation was causing the wall separation. This is a huge mare! So last trim, we were talking about putting on glue-ons (size 5!!) on her to get her wall to grow out a bit and decided to hold off, decided to try deep saw dust in the paddock and boots for all exercise.  And if that didn’t work, try boots and pads 24×7 to see if it changed anything.

So 4 weeks ago, the owner discovered that the feeders had been feeding her alfalfa as a treat! She’s a big mare – maybe they felt sorry for her!!

She stopped that, and this trim, she had ¼” of straight wall, no flair, and GREAT soles!!!


June 2014

Sole… “False” sole, shedding sole, retained sole. When to trim? When to leave it alone?

I’m writing this article on different types of sole and how to manage it because its a confusing topic to understand.

Its important to be able to assess the state of the sole as an owner, and all trimmers need to be knowledgeable about assessing sole durability and depth. There are characteristics that help us assess this, but if the horse has active laminitis, our assessments become crude guesses because the coffin bone location could change.


Sound bare feet are a product of an appropriate diet and are shaped by abundant exercise and the movement patterns of the body they carry. If the body is balanced, the feet are generally symmetrical. If the body has pathology, the feet mirror it.

Regardless of where they live, healthy, sound bare feet have several things in common. When barefoot horses are optimally sound they have a supportive frog, thick durable sole and a low ridge of wall and heel beyond the white line/live sole junction.

How much wall is adequate is variable, it depends on the horse and environment. Some horses accumulate a very thick sole and don’t appear to “want” this lip of wall, but in some feet, that thick sole is an over accumulation.

We need to rely on the horse to tell us what works for them and what doesn’t.

DON’T rely on just lip licking and sighing!! I have witnessed horses undergoing an invasive trim licking their lips, snorting and sighing, and then walking off VERY sore. They are sometimes licking as a sign that the trim is relieving discomfort, but they are sometimes doing it because the trimming is uncomfortable and makes them anxious, much as being in the dentists chair makes us anxious, and they want to encourage us to end it.

The trims I admire and have seen work great look like the trims below. Most of these trims are “transitions”, feet in the first year after having shoes removed.

The September trim below has a very low rim of wall, but for this arena horse it is what works best. This horse works in a soft sand arena and is booted for trail work.

Healthy September hoof

Healthy September hoof

The hoof below is before a 5 week winter trim, and the trim at this level will change the foot very little… most of the wall is shaped by the upper bevel, the bars will be neatened slightly and the lower edge rolled.

The wall is beveled or rolled when trimming so that the edge of the wall wears predictably over a 5 or 6 week cycle and is almost as long at 5 or 6 weeks as it was after trimming. These subtle bevels and rolls allow a skilled trimmer to compensate for imbalance in movement so that the pre-trimmed hoof is still fairly balanced and the boots still fit.

Healthy hoof pretrim

Healthy hoof pre-trim

There are differences in feet from swampy wet areas and hot, arid areas, and the differences are usually accumulating sole and frog. In wet areas, the sole and frog exfoliate easily, and in arid climates, they became a thick, tough horn that resists wear. These different characteristics have advantages and disadvantages.

The Virginia hooves below are easy to trim because they are softer and landmarks are clear and specific. The feet have a good sole and adequate heel, wall and bar for traction, and the frog is lush, wide and open. BUT this hoof can be tender on hard gravel surface, and because the horn (calloused parts of the sole and frog) is softer, it wears faster.

Virginia hoof

Virginia hoof

Virginia hoof

Virginia hoof

The Nevada hoof below has a thick, hard sole, but its more difficult to see the sole depth.  Its durable and tough.

Necvada Hoof

Nevada Hoof

The Nevada hoof below, in contrast, has an over accumulation of bar and sole. Not only is it hard to tell what needs to be trimmed, its physically VERY difficult to trim… these feet are like granite.

Nevada hoof pre-trim

Nevada hoof pre-trim



Wet environment Belgian Draft

Wet environment Belgian Draft

The Belgian hoof above, is shaped by a slick winter paddock. The slightly prominent bars have a natural function, they provide traction in the slippery environment. If the walls are trimmed regularly, the bars self maintain at this length. When the walls are allowed to get excessively tall, the bar also accumulates and must be trimmed when the wall is trimmed. A well beveled wall wears at about the same rate it grows at and this balanced wear should allow the bar to wear at the same rate.

The hoof from the Northern California trail horse below is shaped by hundreds of miles ridden bare on lava rock and hard packed trails. The heel is trimmed to be well above the sole to make the horse more comfortable going over gravel, to reduce sole abrasion and to add to traction. Untrimmed, this hoof looks very similar at 6 weeks to what it looks here. It was prettied up for pictures but belongs to a professional trimmer who merely touches it up occasionally.

Arid Northern California high mileage trail horse

Arid Northern California high mileage trail horse


So you’ve seen some conservative trims, above. Lets look at the opposite.

This looks invasive to me because a "scoop" was carved into the lateral wall. I've see this technique result in extreme lameness

This looks invasive to me because a “scoop” was carved into the lateral wall. I’ve see this technique result in extreme lameness

“Invasive Trimming” is a judgement call because trimming that is invasive on one foot may be necessary on another. Most trimming approaches taught in the US are conservative, but unfortunately one popular approach is invasive and is being taught to beginners who don’t have the experience to know when to stop trimming.

This is probably invasive for barefoot in most areas, and okay for shot feet

This is probably invasive for barefoot in most dry areas,  including mine, and probably okay for shod feet is the wall edge was rasped down. It may be fine as in in boots or on a very soft damp footing. Callous has been removed but the sole still looks fairly thick.

“Invasive” procedures involve cutting into the passive (not weight bearing) bar, removing protective sole, taking the heels down to the live sole plane and shortening the wall in a way that leaves the sole over exposed to wear.

Sometimes rehab feet need what could be, for some feet, considered an “invasive” procedure, such as trimming an accumulation of bar. A routine shoeing trim is technically invasive if your intent is to leave the sole unprotected by a shoe or glue on appliance.

So what to trim or not trim if you aren’t sure? Less is more in most cases. If you don’t know and aren’t a professional with a lot of experience,  get advice  from a conservative trimmer or farrier, or join a conservative trim group like PHCP

Most importantly, carefully observe the horse before and after the trim and have your objective be a more comfortable, balanced and relaxed stride. The horse will always tell you, you need to listen.

My rule now is that, ideally, the horse should be MORE comfortable after the trim than before, or at least as comfortable. If the horse is sore / more sore, the trim could be the reason. Not always, though!

This is invasive in my area for barefoot, the horse would be very tender for weeks, but may be okay shod

This is invasive in my area for barefoot, the horse would be very tender for weeks, but may be okay shod

HINT: If there is a large group of people attacking your trimming guru as being invasive, try to get a second opinion on their approach from another organization! I’m closely aligned with AHA and PHCP but have a lot of respect for trims taught by many other groups. There are many ways to learn, choose a method that focuses on your horses health and comfort.

Very invasive.... abscessing is likely due to the extremely thin sole and bruising

Very invasive…. abscessing is likely due to the extremely thin sole and bruising


Beginning trimmers shouldn’t be doing anything that is invasive.

From the Fresno area, by a "professional" trimmer and instructor

From the Fresno area, by a “professional” trimmer and instructor


I learned from an invasive trimming school that taught hoof mapping; unhealthy feet were over-trimmed to look like what the trainers felt the “healthy” hoof should look like. These horses were uncomfortable, and I was told that discomfort was part of healing and was natural.  I started learning from Pete Ramey, and never looked back as I learned that “transitioning to barefoot” can be easy and comfortable.

Now I understand that the people who initially taught me were caught up in their method of trimming and constantly over-trimmed horses. They trimmed sole and bars aggressively, micromanaging feet, and made excuses for why the horses were so sore.


I’ve trimmed professionally for a more than a decade using a conservative trim approach. I seldom trim sole and attempt to leave a margin of wall that protects the edge of the hoof and provides traction. As a result horses with healthy feet are very comfortable on their home ground barefoot, and many go barefoot on the trail year round.

I look for long relaxed strides at a trot and canter with nice, heel-first landings to assess movement.

Some horses have thin or sensitive soles, or inadequate wall, and need protection. Most of the time, horses coming out of shoes are comfortable without protection in their living environment, but if they are sensitive, they get boots or glue on shoes. Most horses with philological problems are comfortable barefoot or booted if the trim is conservative and appropriate protection is used.

Most horses can grow a thicker more durable sole with the correct trim and diet, but many still like front boots for performance work for the first year or two. Some horses have limited ability to grow a thick enough sole to be barefoot for performance because of past hoof care, breeding or pathology.


I see many photos of horses online who have either had their soles aggressively thinned by owners with good intentions, or whose walls have been trimmed, chipped or worn so short that the hoof has inadequate traction resulting in soles becoming dangerously thin. These are the horses and owners we need to help.

When a horse has a thin sole, it needs hoof protection to move comfortably and rehab successfully. Traditionally, nail on shoes were used, and now we have many alternative ways to protect feet for recreational, performance and rehabbing horses.

Synthetic shoes, casting and glue on boots provide a semi-permanent alternative that stays in place for an extended period of time.The primary advantage is that they avoid concussion and flex more than a metal shoe. Boots and pads can be left on for days or weeks, and should be checked daily. Epoxies and sole treatments also help protect feet depending on the condition and terrain.

For more information on hoof protection:

Hoof Boots
Rehab Hoof Protection
Gluing On Boots


The following pictures are the same hoof taken at different times of the year.


This is is a mid-winter hoof from an Arab on pasture


This is is a early fall (October) hoof from an Arab on pasture. The summer sole and frog have shed.


This is is an early winter hoof from an Arab on pasture before the rains have started

I live in North/Central California. We have very wet winters that start in October and last through March and April. Winters here are as wet as Washington DC and Virginia, where I grew up. Summers are very dry,  with almost no rain but occasional coastal fog…  the soil is a mixture that can be lava rock, granite, loam or sand.

I rarely have to trim sole in this part of North / Central California. In the summer, a thick sole accumulates and protects the hoof from all of the rock on our trails, and before it can get too thick to create a problem, we have wet weather that encourages the accumulated sole to shed.

Some regions are extremely arid and sole builds up in a dense, hard layer that can make horses very tender.


LasVegas hoof pretrim

LasVegas hoof pretrim

LasVegas hoof pretrim

LasVegas hoof pretrim

Raychels horse 002 - Copy

LasVegas hoof pre trim

A day after trim on Jack April 14 (3) - Copy

LasVegas hoof post trim

Jack April 2014 (4) - Copy

LasVegas hoof post trim

Some trimming schools advise removing any sole that isn’t “live”, but where does “live” sole start? What is “false”?? What is a thin sole, and what is normal? And why remove any protection at all?


The soles appearance varies widely

Sole is sole; the term “false sole” is misused and after reading a too many ABC FB shares, I’ve decided to stop using it because it implies that it needs to be removed, and it usually doesn’t unless you live in an extremely arid region like Last Vegas.

When Sole accumulates I call it “retained” because, for some reason, the hoof has opted not to shed it.

Pathological Sole Retention

I see sole retention when a horse with hoof pathology first comes out of shoes… sometimes they retain this sole for 3 or 4 months as the hoof rebuilds itself from the inside out. I used to trim it out, and the horse was always more tender and the feet rehabbed slower, and the horse did better in boots. With these feet, I leave the sole in place but sometimes thin it **slightly** with my sole nippers or a sharp knife to add a little passive concavity. I do very little. When it starts popping out, I help it as it pulls free but leave chunks that are resistant in place.

Environmental Sole Retention

The retained sole that makes me crazy is that found in horses that live on stall mats without shavings or in arid locations like Las Vegas. Even feet with great concave sole shapes will pack solid and flat, and the heels contract…

I think these are the hardest feet in the world to trim, physically (super hard sole) and intellectually because its difficult to know how much sole to remove unless you trim this type of hoof a lot.


I see them primarily on horses that live on mats, and I have trimmed the retained sole, not trimmed it, relieved the bar slightly, nothing seems to work well!

I usually ask people to move their horses or change the stall footing, treat it like I do dietary problems like barns that only feed oat and alfalfa…  if its a problem for the horse, I ask the owner to move the horse. Asa, in Las Vegas, doesn’t have this option!

Thrush Sole Retention

Some horses have had chronic thrush and end up with retained sole that seems to grow to isolate the super tender frog from the weight bearing surface and any flexing in the tender frog area.  I help the client fix the diet and treat the thrush, and this sheds out in a month or two.

Solar Abscess

If a horse has a solar abscess that covers the whole sole, the hoof repairs itself and eventually sheds the sole in one large piece. It may look black and gross under the shedding sole, but I’m not in a hurry to wrench it off!

Unknown Cause

I had one horse who only retained sole in the lateral side of one hoof, all the other feet looked great. The horse was very slightly off on that foot barely noticeable… after 3 months, the owner insisted that I knife it out, it was rubbery and durable, the horse resisted, but I did as she asked, leaving much of it but adding some concavity, and the horse went lame immediately.

Vet xrayed the foot and the lateral edge of P3 had a fracture. we casted DM (dental impression material) into the sole and the horse was immediately better. She retained sole in that area for a year, it finally shed and the mare was sound.


My horses shed sole in moist seasons and accumulate it in dry seasons, and because this isn’t excessively arid like Las Vegas, I leave the accumulated sole alone. If it starts to chip out and is loose, I’ll remove chunks, don’t like to leave pressure points! But I let it shed out naturally until its loose.

June 2014



Occasionally horses are so uncomfortable that they are unable to lift one or more of their feet for trimming. Examples of scenarios I have run into include:

  • Horses  with musculo-skeletal problems (arthritis and muscular problems) in their back, shoulders or hips
  • Horses with laminitis
  • Horses with joint problems like bone chips in  the knee (common in older OTTB’s and jumpers)
  • Horses with hock problems or stifle problems (common in Gaited horses)
  • Horses with extreme ulcers
  • Some PMU mares who have never learned to lift their feet for trimming and are too big to struggle with


Aries, a +17h Draft TB cross, had a very strong passion for living, strong enough that he loved life fiercely in spite of having most of these problems

He had chronic laminitis with severe coffin bone degeneration, along with many musculo-skeletal problems, stifle and joint problems.

His feet and body were so uncomfortable that he was unable to lift his feet for more than a second or two…. but if he got loose, he would canter away at full speed! He had to be walked with a muzzle on because he was so large that he would literally drag people to the nearest patch of grass…

The only reason he lived as long as he did in this state was  1) his pervasive will to live, and 2) he had excellent support from his boarding stable owner and the other horse owners at the boarding facility (who pitched in to help when needed). His owner had financial constraints. so body-workers, trimmers and the boarding facility owner, Michelle of Harvest Moon Ranch, volunteered to help when we could.



Angle Grinders have four characteristics that make them dangerous to use around horses:

  • They generate a blast of air that startles horses… this usually creates the most problems
  • They are loud
  • They vibrate
  • They revolve at a high speed and can easily get bound-up in a horses tail, trimmer hair, lead ropes etc

There are several approaches to using an angle grinder to trim. There is a lot of information online to help you choose tools; search for ” grinder hoof trim” and be prepared to read! I suggest that anyone wanting to try this do their research and practice technique ahead of time with wood, plastic and rubber to understand how the different materials affect your ability to hang on to the grinder.


  • I remove the grinder shield and post handle
  • Always wear protective glasses
  • Tie up long hair on the trimmer and the horse
  • Wear gloves


Grinders throw off a sharp blast of air, and this is the one characteristic that has the potential to alarm horses.

I stand 4 feet from the horse and have the horse on a long loose lead.

I turn the grinder on and off several times, letting the horse watch and get used to the noise, but not showing it to the horse or making a big deal of it.

I then turn the grinder on and “fan” my face with the air, making happy “ahhh!’ types of noise. I then do this to the owner and anyone else standing by….. I blow their hair around and laugh. Sounds silly, but it works.

With the grinder off, I let the horse smell and inspect it

I stand back, turn the grinder on, I fan my face, the owners face, and the the horses face, and, from a few feet away, fan the horses body and legs.

I don’t restrain the horse forcefully, my goal is to engage the horse so that they trust me and the grinder.



TOOLS – I use a heavy duty Makita angle grinder with a paddle switch. My preferred disc is a 40 or 24 grit flap disc, but I have used an abrasive stone disc also. There is a lot of information online to help you choose tools.. search for ” grinder hoof trim” and be prepared to read!

ENVIRONMENT – I stand horses on a piece of plywood to trim. The grinder flap disc has to go to the ground to get a clean edge on the bevel, and most other surfaces create problems or present hazards. Rubber mats catch the edge of the flap disc and can jerk it out of your hand, metal makes a loud noise when the disc is pressed against it, dirt and sand get thrown up and can get in your eyes or spook the horse. Concrete or asphalt can be used, but a pattern of the horses foot will be left on the surface.

HORSE HANDLING – I also like to work in an open area so the the horse can move away from me if it startles or spooks. I ask the handler to stay alert and stay by me, on the same side of the horse that I’m on. If the horse is the least bit active, I have any observers stand on my side of the horse, behind me and at least 3 feet away.

TRIM OBJECTIVE – The objective is to use the edge of the flap disc to etch a bevel around the edge of the hoof from the lateral (outside) heel wall to the medial (inside) heel wall. Depending on the angle of the hoof wall and the wall thickness, the bevel will be from 1/4 to 1/2 inc high.

The angle of the bevel is roughly perpendicular to the ground.

The top edge of this bevel should parallel the coronet band or growth ring around the front half of the hoof.

If the horse has high heels and is able to life his heel, I get the horses foot at edge of the plywood so the the heels are hanging off the edge, and try to bevel the heels down with the grinder… this sometimes works ok, sometimes doesn’t work at all! Each case is different.


When the training and desensitization goes well, I run through a mental check list, then have the horse holder stand on the same side of the horse as I am on, and I turn the grinder on and, working on a front foot, I lightly touch it to the lower edge of the wall, where the bevel will be. By this time the horse is usually alert but relaxed, and I can continue around the front feet, and then the back.

grinder_TFTT_Aries_01  grinder_TFTT_Aries_02 grinder_TFTT_Aries_03 grinder_TFTT_Aries_04 grinder_TFTT_Aries_05 grinder_TFTT_Aries_06 grinder_TFTT_Aries_07 grinder_TFTT_Aries_08 grinder_TFTT_Aries_09 grinder_TFTT_Aries_10 grinder_TFTT_Aries_11 grinder_TFTT_Aries_12 grinder_TFTT_Aries_13

January 2014