States is in a 1930 handbook, Technical Bulletin No. 171 written by C. A. Plaskett for the U.S. Department of Agriculture. Plaskett was known for his extensive testing and defining of various components of transport packaging. The USDA Forest Service revised and expanded it in 1964 as the "Wood Crate Design Manual", Handbook 252. Construction Although the definition of a wooden crate, as compared to a wooden box, is clear, construction of the two often results in a container that is not clearly a crate or a box. Both wooden crates and wooden boxes are constructed to contain unique items, the design of either a crate or box may use principles from both. In this case, the container will typically be defined by how the edges and corners of the container are constructed. If the sheathing (either plywood or lumber) can be removed, and a framed structure will remain standing, the container would likely be termed a crate. If removal of the sheathing results in no way of fastening the lumber around the edges of the container, the container would likely be termed a wooden box. Design There are many variations of wooden crate designs. By far the most common are 'closed', 'open' and 'framed'. A Closed Crate is one that is completely or nearly completely enclosed with material such as plywood or lumber boards. When lumber is used, gaps are often left between the boards to allow for expansion. An Open Crate is one that (typically) uses lumber for sheathing. The sheathing is typically gapped by at various distances. There is no strict definition of an open crate as compared to a closed crate. Typically when the gap between boards is greater than the distance required for expansion, the crate would be considered an open crate. The gap between boards would typically not be greater than the width of the sheathing boards. When the gap is larger, the boards are often considered 'cleats' rather than sheathing thus rendering the crate unsheathed. An unsheathed crate is a frame crate. A Frame Crate is one that only contains a skeletal structure and no material is added for surface or pilferage protection. Typically an open crate will be constructed of 12 pieces of lumber, each along an outer edge of the content and more lumber placed diagonally to avoid distortion from torque. When any type of crate reaches a certain size, more