Or painting the end with almost anything. Wood glue thinned with water is favored by some. Any can of spray paint you have around will do. Old can of paint for your batroom?
Many,many moons ago,while staying with a good friend in New Hampshire,i noticed that in seasoning sections of apple and other woods for carving he sealed the ends with this odd-looking compound.Turned out that it was a commercial,rosin-based product,that he normally used for grafting in his orchard.
What impressed me was that the stuff was so stout that it not only sealed the end-grain for moisture,but actually mechanically held it from checking...
(At least the more moderately-sized dia. sections...).