Yes — a Traditional Root Treat
Horses can eat parsnips, and in colder parts of the world the parsnip has been a horse treat for as long as carrots have. It is a root from the same family, grown in the ground, pulled in winter when the pasture offers nothing interesting, and its flesh is dense, sweet and satisfyingly crunchy. Fed with the same sense you would feed a carrot, a parsnip is a good addition to the treat bucket — it just arrives with one extra preparation step. The old way was to leave the roots in the ground through the first frosts and lift them as needed, and a box of parsnips kept in dry sand in a cool feed room still holds them in good condition deep into winter.
Root Yes, Tops No
The leafy green tops are the part to leave behind. Parsnip foliage is an irritant — the sap in the leaves and stems can blister skin, horse and human alike, especially in sunlight — and there is nothing in the tops a horse needs. Trim them off at the crown before the root reaches the feed room, scrub the root itself under the tap to clear the soil its ridges hold, and what you are left with is the only part anyone feeds. Gloves are a sensible idea for the human doing the trimming, too.
Sticks, Not Chunks
Cut a chunky parsnip into crosswise chunks and you have made dense, rounded lumps — the exact shape a keen horse can swallow under-chewed and lodge in his gullet. Lengthwise sticks solve it the way they solve it for carrots: the pieces break across the grain under the teeth and travel down safely. Parsnip is a harder, denser root than carrot, which makes the stick rule more important here, particularly for old horses whose chewing is no longer thorough.
Sweeter Than It Smells
A parsnip smells earthy and tastes, to a horse, surprisingly sweet — frosts sweeten roots further, which is part of the winter tradition. That sweetness is sugar, in roughly the same territory as carrots, so the portion discipline is the same: a stick or two as a treat, and a rare appearance only for the easy keeper, the cresty pony or the horse whose vet watches his sugar. The rest of the yard can enjoy them through the winter without a second thought at treat scale.
Introducing an Unfamiliar Flavour
Most horses have never met a parsnip, and the earthy smell earns a suspicious sniff and sometimes a dropped first stick. Offer one stick on top of a familiar feed, or hold it alongside a piece of carrot, and let him come round in his own time — many converts are made by the second day. A horse who never converts loses nothing; his diet is complete without it, and the sticks keep happily for the horse in the next stable.
Noting parsnip sticks, tops trimmed, in his winter routine in KinsLe's Care Teams means a covering helper prepares this treat exactly as safely as you do.