A portable saw mill is an easy way to use wood scraps from your property that would otherwise decay and turn them into usable wood. In addition, loggers tend to leave everything they can't sell directly to commercial milling operations. Portable sawing doesn't require being able to saw 1500 feet per hour; you need to do the average job in a single trip. Circular saw blades are faster than other blades for milling wood, and most high-production sawmills they use them.
Buying logs to make wood to sell on the market in low volumes is not all it seems, and in small production scenarios, larger factories know that the cost of production in portable mills is lower in many cases. The Imony 36 inch portable chain saw is easy to install and accepts chain saw bars up to 36 inches, suitable for quite heavy trunks.