I have been asked, more than I ever expected, questions about my choice of arena footing. As any horseperson is well aware, in the horse world, everyone has their own opinion about everything and their opinion is the only right one.
With that and one more caveat, I am taking a deep breath and going out on a limb to share with you my opinion on footings. The caveat is: this is the footing that works best for me. Your situation may be far different depending upon material availability, weather conditions, riding discipline and personal experience.
In the Pacific Northwest we have a plethora of trees. When I ride over the Willamette River on the Canby Ferry (blessed to have it just two miles from my house), there is nothing but Douglas firs and assorted varieties of maple and other deciduous trees as far as I can see all the way down to the bank of the river. From this vantage point, I can most easily imagine what it was like for Lewis and Clark as they arrived here after passing through so much high desert and open plains. The lusciousness must have felt like arriving in the Garden of Eden, yet the density of the growth must have made their passage untenable except when able to traverse by waterway.
So it is natural that one of the top footing choices here is a wood product. I use what is called hog’s fuel or hog fuel. So named I have been told, because the machine that grinds huge tree stumps is called a hog and the raw material is its fuel. Factually, I find the name a little disconcerting because it seems to my literary mind that the end product should not be called “fuel”, since that is the same name as the raw material, but since they never asked my opinion regarding it’s name, so be it.

The resulting hog’s fuel is semi fine ground up tree stumps where the material ranges from fine (like garden mulch) to coarse (like the smallest pieces of wood you might try to start a fire with when rubbing two sticks together). When trying to describe it, I have gone so far as to gather some up in a Ziploc bag and mailed it to people who live too far away to visit my farm in person. Hog’s fuel should not be confused with the stringy cedar material sometimes called pole peelings or affectionately referred to as gorilla hair. I do not like this material as it is hard to spread and harrow, feels trippy and slippery when I have ridden on it, apparently can turn into a dusty peat moss concoction as it breaks down, and some horses (I have one) are allergic to cedar.
Hog’s fuel has so many good things to say about it. It is “relatively” inexpensive wherever there are trees. Mine is made from tree stumps left over from logging so I don’t worry much about foreign materials. It is made by a company aware of it being used in a horse application so they are cautious about the trees they grind - knowing that black walnut and yew are so harmful to horses. I know there is no guarantee that an unwanted variety could be used accidentally - but in the 20 years I have relied on this material for not only my arenas, but also pathways and gateways, I have never had a problem. It works well to mitigate mud in the winter around gates and high traffic areas if you install it on top of heavy road fabric and/or gravel depending upon your circumstances.
It holds moisture so needs less watering to keep down the dust; it is in large enough particles that any dust that is stirred is usually pretty heavy so it stays low to the ground. It requires very little harrowing and maintenance. I usually mainly need to pull it off the walls along the track. If it requires frequent harrowing or I see or feel any slipping by the horses, it simply means that it is time to add a couple more inches to the top. I started with 8 inches and as it breaks down, I add a couple of inches to maintain it at 7-8 inches in the indoor and 5-6 inches in the outdoor. In the 12 years I have had it in the indoor, I have never had to remove any of it and really don’t ever expect to - I just add more as needed. The outdoor I add some maybe every couple of years and in the 8 years have not had to strip any off - though I cannot be sure I won‘t have to someday. The outdoor is an all weather surface and gets hit hard with a lot of rain in the winter, and a lot of direct sun in the summer. I have never had to water the outdoor but I do water the indoor depending on traffic and weather conditions.

I feel fine using the indoor for lunging and turnout. I don’t like using the outdoor for lunging because the fabric that makes the outdoor all weather is just 5-6 inches under the surface and I don’t want an errant horse to dig down to it and risk slipping or ripping it. However, the outdoor is in my winter turnout pasture and handles the horses rolling on it and galloping across it just fine. I am meticulous about cleaning up manure in both arenas - it helps with maintaining the longevity of the footing and no one, horse nor rider, needs to be breathing in broken down manure dust.
The best part is the fact that my horses stay sound on it, the maintenance is so easy, and the material is mostly readily available when I need it. I use the same material in both the indoor arena and all weather outdoor arena, so the horses have no adjustment going from one arena to the other. For FEI dressage riders, sand or sand mixed with other products is the ultimate choice due to competition regulations. But sand by itself and sand mixtures have a host of issues I am not willing to deal with - maintenance, cost, dust (I wear contact lenses) and more. Hog’s fuel may not work well without adding something to it for hunter/jumpers and I wouldn’t expect it to work at all for reiners. But for pleasure riders and dressage riders, you could do far worse.
Best of all, I love watching horses being ridden on it as I can see the cushion it provides them on the landing and the support it provides them on the take off. You can feel the spring it gives the horses as you ride them, too. And, living where Lewis and Clark once strode, I really like the natural look of the wood against the backdrop of the trees and pasture… well almost natural, except for the exclamation of the white dressage arena rail and letters that would let, even Lewis and Clark know, that a dressage lover rides here.