Ocean temperatures and isotopic compositions through time

A trailer attachment for a tree harvester is disclosed herein. The trailer attachment consists of a main frame having a grapple frame supported thereon through a support frame and the support frame is rotated about a vertical axis on the main frame while the grapple frame is supported for pivotal movement about a horizontal axis on the support frame. First and second biasing means are interposed respectively between the main frame and support frame and the support frame and grapple frame so that the grapple frame is returned to a predetermined position wherein an upper support surface extends generally horizontally and the horizontal pivot axis extends generally parallel to the main axle for the trailer.