Good info here. Thanks.
Above timberline, often the compass headings are used in conjunction with the ‘handrail,’ technique, which has been often discussed on BPL. A problem is that the faded green to note timber line on the USGS maps can fade, either on the original or when copying, or using commercial copies like Nat. Geo., which also have various errors. Many of the plastic map materials are also particularly prone to fading. Then the handrail is gone. So reluctantly, the USGS paper map can be cut to desired size, and laminated in a very thin (1.5-3 mil) material. Then the timberlilne remains clear for a few years at least, and the map remains dry. Many of the USGS 7.5 minute series have not been updated for over a decade, so thanks for the link to the declination update site.

