Right or wrong I do it all the time. The right answer is that it’s a risk. Depending on what risk you are willing to take, It might be something you should never do. But I love to see a free horse running as we ride. Their emotions just seem to hit a high as they realize they are totally free and can enjoy the outing.
I start my young horses by letting them tag along on trail rides as yearling. Unless we encounter other horses, I let them just run loose. If I see approaching riders, a barbwire fence or some other hazard, I’ll collect them and put them on a lead.
As they get older, I’ll start putting packs on them and let them carry a light pack where they can feel it flopping against their side and feel the cinch and saddle parts working. By time I’m ready to start actually riding them. They are very comfortable with most trail obsticles, bridges, water crossing etc.
The biggest problem with loose horses is pecking order. If you have a horse that may want to insert himself into the line up in a different order, kicking and other agressive behavior may happen as the horses defend their position in the line. This can especially be a problem if you are encountering other strange horse along the trail. I always keep a lead on in areas where I have a high probability of encountering other horses. Same problem goes for hikers. My horses will run right up to stranger and beg for a treat or to be petted. This could possibly really scare a hiker who is not familar with horses. A loose horse can easily bump a hiker loaded with a big pack off the edge of trail.
I can’t tell you how many miles I’ve ridden with a loose pack horse just following. Usually in the middle of the group, one rider behind to make sure nothing falls off and they pack horse doesn’t get distracted and somebody leading. I would never allow multiple pack horses to be loose at the same time. I don’t need to see my gear getting squished as they both try to squeeze between a couple of trees at the same time.
You can see two yearlings following our group in this photo
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Here is my mare being used as a pack horse following us through a large boulder field
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