Logging truck

[3] The coming of World War I and the resulting demand for the Pacific Northwest's Sitka spruce for airplanes "established log trucking in Washington".

[3] The United States Army assigned thousands of men to the Spruce Production Division to build roads into western Washington to harvest the dispersed stands of the best trees.

[3] After the war ended, a plenitude of surplus military trucks made their adoption attractive to logging companies, particularly smaller outfits that could not afford expensive locomotives.

[4] There are two main types of modern logging trucks—those used on rough ground and trails in the forest where they are felled and those used for transport on normal highways and roads.

[6] Timber is commonly grown in hilly country unsuitable for farming and so the ability of a log truck to climb a gradient is significant.