Multiple studies conducted by the Virginia Tech Department of Wood Science and Forest Products, in collaboration with the USDA – Forest Service (Blacksburg, Virginia) found that manufacturers of new pallets use both hardwood 64% by volume) and softwood (36%) material.

This lumber comes from lumber mills, primarily from sustainably managed forestries in North America. Pallets may be constructed from a combination of both hardwood and softwood. Wood used to manufacture pallets is too imperfect for use in furniture.

The two most common wood species are Southern Yellow Pine (SYP) and oak. Southern Yellow Pike is used in 19% of the time; oak is used 17% of the time (by volume).

Soft Woods

Southern Yellow Pine species accounts for 54% of softwood lumber; whereas spruce, pine and fir species account for another 36% and Douglas Fir for 4% of softwood volume.

Hard Woods

For pallets built from a single species, oak is used 27% by volume; maple is used 7%; other hardwood species are used 5% in volume. However, most hard wood pallets are built from a mixture of hard woods.

 

Reference:
Material Use and Production Changes in the U.S. Wood Pallet and Container Industry: 1992 to 2006, Robert J. Bush and Philip A. Araman, 6/1/2009
https://palletenterprise.com/view_article/2866