Chickweed
This common pasture weed can be found in moist areas in spray free gardens or pastures. We use it internally for humans but your horse will probably eat it in the paddock anyway so we won’t go into that.
Chickweed is a very cooling herb.
Externally it can be used for hot angry skin conditions, to sooth and help to decrease itching.
You can combine it with other herbs, such as Calendula oil, or use it on its own.
You can make an oil, but you will need a little heat, or just zizz it up in your food processor.
If you do that, apply it directly as a paste and leave it to dry, or bandage it on. Your choice will depend on the situation.