Forest shading on Garmin topo maps?

[Donho2]

Why do Garmin topo maps (I have the Topo Southwest 24) have no delineation for forest shading and open grassy or rocky areas.  Mountain areas with forests appear as a solid green. National Geographic topo maps have this feature.  Can I get it for my Garmin (Oregon 550)?

[maps4gps]

Because Garmin choose not to make polygon symbols for grassy and rocky areas. 
When is green not green?
The 'forest' shading is usually used to show landownership of parks and nationa forests and not that the actually vegetation is treets or grass.  There is a forest/tree polygon, but the information in polygon form is not easy to come by.

[Donho2]

On National Geographic  and USGS topos the maps are shaded green for wooded cover and are left white for grassy or rocky areas.  The Garmin maps will shade the entire area as green not distinguishing between wooded and non-wooded areas.  Nat Geo maps that can be used with the Magellan Triton series GPS can use these Nat Geo maps and the user can navigate using this added information. This information can be useful for navigating, hunting, rock climbing, etc. However, I have a Garmin GPS and want to know why Garmin maps lacks this feature?  Or are there maps with wooded cover shading available for the Garmin?

[maps4gps]

On National Geographic  and USGS topos the maps are shaded green for wooded cover and are left white for grassy or rocky areas.

Those are 'raster' image type printed products.  USGS produced vector data for about 4% of the 48 states, however, this seams to have ended almost a decade ago.

The Garmin maps will shade the entire area as green not distinguishing between wooded and non-wooded areas.

As I previously mentioned - the green is used to show landownership/use (as in areas for recreation) and not to distinguish between forest and non-forest areas.

This information can be useful ...

Agreed.  I would much prefer knowing where the timber-line is and the clearings in the forest than that the other side of the National Fores/Park is 20+ miles away.  

Nat Geo maps that can be used with the Magellan Triton series GPS can use these Nat Geo maps and the user can navigate using this added information.

I believe they use a raster image and not vector data.  Each has its strong and weak points.  Garmin does not currently support raster images on their GPSrs.  Point this out to Garmin; they are behind Delorme and Magellan and it will eventually decrease the sales of their units.

I have a Garmin GPS and want to know why Garmin maps lacks this feature?

That would be a question for Garmin to answer; call there tech support.  If you get an answer, please share it with us.   I would guess it is because the display technology is 5+ years old and that most users are more interested in finding the recreation areas than knowing where the trees are and are not.

Or are there maps with wooded cover shading available for the Garmin?

Not that I am aware of; at least not for large areas.  Early last year I was able to convert some raster landcover data to vector polygons; however, it takes nearly 10 hrs of 'hands on' interactive processing for a 1x1 degree area.  If a single stand-alone program was available to do this, I would process it all - might even distinguish between the three classes of trees.   The raster data itself is not nearly 100% reliably classified, so there could be large discrepencies between the landcover image data and what is shown on the printed topo quads.

edit: fixed quotes

[maps4gps]

Garmin GPSr units are capable of displaying LULC data

OK, that is correct depending on how much detail/destinction you want in the units.  Water, glacier, transportaion, forests, wetland and sand are there.  Without using custom types, how would you distinguish deciduous vs evergreen vs mised forest, or woody vs herbaceous wetlands, or include pasture/hay, row crops, small grains, other grasses, quarry/strip mine?  The sand symbol would be somewhat misleading if used for bare rock/sand catagory and its pink color is also used on my 76csx for glacier and man made areas.

The source photography for the 250K/100K data is almost 3 decades old.    Satellite sensors have since been used to create a 1992 and 2001 raster data set.  In my local area (CO foothills to across the divide), the NLCD remote sensor mapset from 2001 compared much better with recent 3 and 1 foot resolution 'photography'.  USGS+ are currently developing a 2006 raster dataset.

How would one classify burt over areas (i.e. CA or Yellowstone NP) or dead but standing trees from pine bark beetle disease?

[maps4gps]

Is the 'invisible labeled polygon type' a 'standard' type, I do not see it in the cgpsmapper manual?

I have done something like that - use the standard forest type and put deciduous or evergreen or mixed in the name field.

[Boyd]

Using custom types is one way and I believe that is what Boyd did with his Pine Barrens mapset. This gives you a visual reference within the GPS.

Yes, this is a real annoyance with Mapsource. Why can't Garmin give their computer software the same custom type abilities as their GPS'es have? instead they keep adding other "eye candy" features (and new bugs) with each update.

I found excellent LULC (Land Use Land Cover) data for New Jersey on the state website. This question came up in an older thread, and I was able to find some links to similar data for the OP's state with a little Googling. Try searching with terms like the name of your state, GIS and LULC and you may be surprised at what is available.

I went much farther than just the green shading found on USGS maps myself and created a LOT of custom types which gave a more "photographic" look to my map. But if you just want to do green shading like the USGS maps, that's pretty simple. But, of course, you will need to make your own map. As to why Garmin doesn't offer this... who knows? I wouldn't hold my breath waiting for them to do this personally.  

[maps4gps]

I see.  I was wondering what those codes could be used for if they were invisible.

[Boyd]

Whoa - that is very cool! How did you do it? Is there a way to turn this into an installable mapsource file?

For the OP - on the Oregon 550 you can now use *real* USGS raster maps with Garmin's custom maps feature.

[Boyd]

Sounds good. FWIW, this is what the same area looks like on my Oregon

[Seldom]

Will you be setting up a tutorial for your snazzy MapSource display?

[Boyd]

BTW, got the PM and responded. Thanks for all the detective work on this!

As an aside, I just got a Nuvi 1350 and to my dismay, it renders all the topo maps I've tried really poorly. For one thing, contour lines are too big and fat - they look like roads. But a bigger problem is that it doesn't render the wetlands type correctly. It is drawn the same as water, so it gives the appearance of huge lakes in lowland areas where there aren't any. I have never seen another Garmin GPS which does this.

It also doesn't seem compatible with Mapwel's extended custom types. The map in the examples we're discussing here is basically blank with sort of a noise pattern covering most of it. I believe it works correctly with the cgpsmapper re-defined types however. I have an older map where I replaced Garmin's wetland symbol with my own and it looks fine. In that same file I also redefined the contour lines so they would look better on my Nuvi 205, and they look good on the 1350 also.

The new pedestrian mode is pretty cool though, and it makes the topo maps display a little better.

[Boyd]

Here's a followup on this topic. The Nuvi 1350 inspired me to see whether I could trick it into displaying a topo map the way I wanted, so I started work on a project that I've been thinking about for awhile: to develop a style that looks more like a USGS 24k topo. This is a work in progress, but sometime around New Years I will upload a new version of my "Map of the Pines" (Southern New Jersey) here.

I'm learning a lot along the way, and am breaking all of the rules in how I classify map objects and use custom types. I put all the pieces together today for a beta version and finally figured out how to make this work in Mapsource as well as the GPS. I was pleasantly surprised to see that it looks very similar on the GPS and the computer.



One big problem is that the TIGER road data just doesn't have enough types of roads. The classifications exist within their system, but by far the largest number of roads are classified as "residential" while in reality it's a jumble of numbered county routes, side streets and even dirt roads. So I'm doing a lot of manual editing while comparing with the USGS topo maps.

Every object on my map is a custom type. After initially creating these with a text editor and cgpsmapper, I started tweaking them with the online editor at http://ati.land.cz/gps/typdecomp/editor.cgi. What a terrific tool! Among other things, it lets you choose the text size for labels. I don't know any other way to do this, and it's really helpful on the Nuvi, which lacks menu control over the map appearance.

Here's another work in progress screenshot from the Nuvi 1350

[maps4gps]

Boyd,

   Another fantastic creation.

   Census transportation is a big challenge.  I have found block long segments of city streets code 'interstate' and segments of Interstate coded residential; and 'everything' inbetween.  Differences between counties for the same class of road and many variations of how a US, State, countty, and Forest Service roads are designated/named.

[Boyd]

Thanks! BTW, notice the elevation numbers in the screenshots above. Yet another "improvement" of the Nuvi 1350, it makes them look like alphabet soup!