I'm a hoofcare practitioner who also doesn't do shoes, tho I used to, before I started really learning.... As someone else pointed out, it's not ideal to judge a farrier without having been there to see what they started with and quiz them on the whys & wherefores. It's also difficult to get an accurate full story just from some pictures. So I'm just telling you what I see. While many of the specifics of the trim & shoe job appear problematic, it's not necessarily because you have a bad farrier. Who knows - perhaps you've only just started using them & they're picking up where the last one went wrong.
The growth rings indicate she has had a lot of metabolic upsets and her diet may still be a problem, as it obviously has been until recently at least. This may be the cause of the flaring(separation), tho mechanical issues will have contributed. Carbohydrate overload, be it from grain or rich pasture, etc, is a big problem, as is feeding horses rich meals, with hours in between is also a probelm for horses who were designed to eat low grade, high fibre in tiny amounts nearly constantly.
Her front feet are quite high heeled and the heel buttresses have underrun a bit too(too forward). Looking at the sole pic, it seems they are very flat, thin soled feet at the front. It's impossible to tell accurately just from a few pics what's needed, but I would possibly not lower the heels ATM until she's grown a bit more sole at the toe. Her heels will likely be weak & sensitive from lack of use, so lowering them now may force her into more toe-first landings which will create & exacerbate problems.
I'm also concerned that it looks like the farrier has carved a lot of frog away & may have rasped into the sole at the toe(Perhaps to 'stand her up' more, as some like to). This is asking for trouble, especially given that there is likely little sole protecting P3 at the front anyway. I also agree with what others have said that it looks like she's shod too small.
The hairlines are a distorted, especially at the rear, from excess pressure at the quarters - this is more common than not in shod horses.
The back feet also look very shallow & perhaps short at the toe. The outside pic makes it look like the grain of the hoof at the heel is nearly horizontal - the heel is badly crushed. But the inside views show a reasonably nice heel height & angle. I'm thinking (& hoping) that the bullnose effect is because the farrier has backed up the toe too far, rather than the horse's feet growing in that manner.
The shoes all look like they're set a little skewiff too, esp the HL. The front feet look possibly steeper in angle to the backs, which is not generally good. While I'm def. Not a fan of letting hooves overgrow & find 6 weeks is frequently too long between trims or resets, she looks like she couldn't afford to lose any more toe at all, but perhaps a little heel.
I know very little about horses' feet so I am looking for opinions on my mare's.
How does the saying go... Ask advice from 4 different horse people & you'll get 10 different opinions. You'll easily find all the different opinions you can stand, as you've seen above, but that's not to say you're getting good information, be it from horsey forums such as this or from professionals such as your farrier. How do you know whether to listen to me, who says her heels are high, or to someone else who says they're nice?? It is up to us to educate ourselves on things that matter, so we can make *informed* decisions. Pete Ramey hoof care heals founder in horse’s navicular disease farrier
is a good starting place with lots of info. While I don't personally agree with some of the specifics they advise on this site, Treating Founder (Chronic Laminitis) Without Shoes--Home Page
is also another very informative site.
If I could keep her barefoot I would but with the work she does the quality of ground here, and her soft TB feet it just wouldn't work.
Like I said above, educate yourself & make up your own mind, but my take on the above would be to use hoofboots to protect her where necessary until her feet become strong enough - after all, shoes are only protecting the ground surface walls anyway, not her thin soles & sensitive heels & digital cushions. I would definitely want to protect the soles from bruising & abscesses that would set you back a long way. I would possibly also use pads with added frog support in the boots for the time being, to get those heels in use while keeping her comfortable for heel-first landings. Having soft feet is generally due to management & diet, not due to her being a TB. I think you would see a lot more & quicker improvement in her feet if she were bare & booted when necessary.