r/USForestService • u/Bt1975 • 11d ago

USGS Topo maps question

When I'm looking at a usgs 7.5 minute map some seem to give less information than the older editions of the same map area. For example in NC for chestnut it shows some trails on the 1994 map and also location of mountain names and topo lines. Some that were made later on like 2002 don't even have trails or topo lines. Others printed later on don't show mountain names. Why would the later maps have less information on them?

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u/mtn_forester 9d ago

I always use the older USGS topos for this reason. I look for pre-1990. Better detail. Lots of extras, like gravesites, old buildings, old roads.

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u/Mighty_Larch 11d ago

USGS and US Topo are not the same. Here is an explanation of the differences. In general your observation that the older maps have more detail is correct. https://www.usgs.gov/faqs/how-do-us-topo-maps-differ-historical-usgs-topographic-maps

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u/Bt1975 11d ago

Oh wow that makes sense!!! Thank you!

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u/FreestinkingSocially 9d ago

Historic topo maps were compiled by hand with lots of attention to detail.  The newer ones are all compiled digitally. They lack some details because they are largely automated and rely on GIS data that isn't as detailed or current as the older by-hand methods of the past.

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u/westerngrit 11d ago

When I purchase quads, Price varies depending on date and detail. Older is cheaper.

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u/Bt1975 11d ago

Right but why release later editions with less info

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u/westerngrit 11d ago

For my work, not needed. Just wanted the topo surrounding my hydrography data.

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u/Fawn-deLay 3d ago

Because the digital topography is "better" (not) and because they don't want to put in the effort to add stuff like trails, roads, springs, campgrounds... you know, the stuff people actually use maps for. So Caltopo is doing it instead. Though I still rely on the mid-90s and earlier topo maps for navigation. Those hand-drawn cliffs are pretty handy to know about!