pitch wrote:
Expanded metal grating. I have surplus military cargo pads. Metal strips with holes in them. Grass (lawn) has grown thru and unless you know where they are they can't be seen. I mow across them and generally never think of their existence. With your drier Western climate I don't know if they would be covered as well.
https://www.bing.com/images/search?q=marston+landing+mat&id=F62B38B6A4247FF938DB7329CF4C9D0365859F80&FORM=IQFRBA
PSP or Perforated Steel Planking, originally known as Marston Matting. Its military runway matting. The Viet Nam era runway mat is different and doesn't have the holes.
Charles