OnX/GoHunt maps error?

[Gapmaster]

I won a lifetime elite membership with OnX several years ago and I run it religiously in the backcountry. I’ve very rarely found discrepancies with private/govt land boundaries. However, I have come upon a location where I’m confused. I’ve found an area, which I know is bordering private land, it has a long straight cleared lane approximately 1-2 miles long (like you would fence) over several ridges. The East I have assumed was private. The West side being public.

Here’s my issue. OnX shows the line 3-400 yards further East than what I’m seeing in the field. I checked GoHunt’s data, exactly the same as OnX. The USGS topo map I have isn’t detailed enough for that small of a difference. Right now, im being smart and staying West of the visual line. I should add that there isn’t any signage or paint along this line. But I’ve let several nice bulls go due to this issue. My question…Is OnX and Gohunt using the same information? Any advice on how to verify? Could the line actually be further to the East and maybe I’ve encountered a fire break type situation?

 

[kwackkillncrew]

See if the county or city you are near has a gis parcel viewer and see where the cutline is compared to the lines. I am sure they are using the same info. All the information is public info and they got it from somewhere. It sounds like a surveying cut line to me.

 

[PRC]

Try using Gaia

 

[roadrunner]

Your best bet is to check with the county.

 

[dieselchessy]

Are there no survey markers/monuments in the area? Usually pretty easy to locate a marker and confirm your mapping overlay is accurate for where you are at.

 

[Gapmaster]

Are there no survey markers/monuments in the area? Usually pretty easy to locate a marker and confirm your mapping overlay is accurate for where you are at.

Haven’t located any. Been all over the area for several years on and off. My gut says the mapping systems are wrong. But just want to verify.

 

[dieselchessy]

Haven’t located any. Been all over the area for several years on and off. My gut says the mapping systems are wrong. But just want to verify.

If you get a USGS quad map with townships, range, sections, you can very often find the monuments on section corners and such. I’m my area the state lands are almost always marked where they adjoin private.

 

[def90]

I won a lifetime elite membership with OnX several years ago and I run it religiously in the backcountry. I’ve very rarely found discrepancies with private/govt land boundaries. However, I have come upon a location where I’m confused. I’ve found an area, which I know is bordering private land, it has a long straight cleared lane approximately 1-2 miles long (like you would fence) over several ridges. The East I have assumed was private. The West side being public.

Here’s my issue. OnX shows the line 3-400 yards further East than what I’m seeing in the field. I checked GoHunt’s data, exactly the same as OnX. The USGS topo map I have isn’t detailed enough for that small of a difference. Right now, im being smart and staying West of the visual line. I should add that there isn’t any signage or paint along this line. But I’ve let several nice bulls go due to this issue. My question…Is OnX and Gohunt using the same information? Any advice on how to verify? Could the line actually be further to the East and maybe I’ve encountered a fire break type situation?

Yes, they are likely using the same county GIS data.

You could go to the county and look at the maps and ask them questions about it. It’s possible the landowner just moved his line over hoping no one would ever notice or raise a stink.

 

[trailblazer75]

Yes, they are likely using the same county GIS data.

You could go to the county and look at the maps and ask them questions about it. It’s possible the landowner just moved his line over hoping no one would ever notice or raise a stink.

I've run into this exact issue and showed the landowner the mad. He was mad but he was wrong and I got to haul the buck I'd just shot out of there. He however had marker stones in his field which he'd clearly ignored when putting in fencing.

 

[Lwilliams]

Go to the county assessor in that county and look at their maps. You can also look up corner records that local surveyors have filed to see what corners may or not not be in the area. Some places have this information online, others you have to do in person yourself.

 

[Dwnw/theAltitudesickness]

 

[Dwnw/theAltitudesickness]

I am currently seeing a few map discrepancies as well with On-X maps. Spots I know where the boundary is with public & private. Same with a known fence line. Haven't double check to see if they are shifted on gohunt maps. You can see the distinct fence lines on both sides of this piece of private that juts into public.

 

[Macintosh]

I think this is normal and expected, and is the reason for their disclaimer ("not to be used for ...blah,blah"). On the areas I live and hunt I expect there to be some degree of offset between the boundaries shown on the screen versus the boundaries on the ground. Generally this is on the order of 15-50 yards depending on where. I also see contigugous parcels sometimes shown with a gap between them, etc. It seems somehow digitally the puzzle pieces dont all fit together perfectly. I just expect it. It does not at all surprise me that some areas the difference is larger.
Below is my property where I live. Boundary markers have been there since the 1700's and they are about 4 feet from the woodline just North of the horizontal red line. Onx shows my boundary 20 yards south of there.

 

[Dwnw/theAltitudesickness]

I have worked with some surveyors and they have shown me a few things with their GPS units/ Tremble units. There is a reference coordinates system or basemap that has to be selected for usage. I don't remember the correct term for it. All survey points in that area, construction site, job etc. all have to using the same one. Otherwise survey points will be off. If any survey work guys were on here I think they could explain what I'm trying to say clearly. I would bet the imagery layer is different than the property lines layer.

 

[LongWayAround]

OnX etc. use the data provided by county assessors to overlay shapefiles on satellite imagery. I would not call the blm fences above a discrepancy, that looks pretty close.

For the OP, 300-400 yards is much more than I would expect. You mention that you know it is the private border but then say that you assume it to be.

Is it a narrow strip of private land (like a mining claim) or is it just a path that you can see? No fence?

You can buy a plat map and check against it or do a search for recorded surveys from the area.

 

[BuckRut]

You can also go and see if your location marker agrees with the boundary. Some of these discrepancies are only with the satellite imagery and not necessarily with the GPS data. When you are trying to apply an image of a sphere in a flat manner there has to be some fudging and the image doesn't match exactly.

 

[LongWayAround]

I have worked with some surveyors and they have shown me a few things with their GPS units/ Tremble units. There is a reference coordinates system or basemap that has to be selected for usage. I don't remember the correct term for it. All survey points in that area, construction site, job etc. all have to using the same one. Otherwise survey points will be off. If any survey work guys were on here I think they could explain what I'm trying to say clearly. I would bet the imagery layer is different than the property lines layer.

The GPS connects to a base station/reference network that transmits from a point of known location to provide your coordinates. The GPS stores latitude/longitude and converts them to northing/easting for construction purposes. I'm not exactly sure what you mean about all having to use the same one: you could have a guy setting a base up on site and another guy using a reference network and they should be getting roughly the same information. The network that we use often shows multiple reference stations with high accuracy. "Using the same one" does become more important for vertical information when you start talking about gravity drained systems.

Obviously that's pretty condensed but hopefully it helps.

 

[Bearded Bowhunter]

The GPS connects to a base station/reference network that transmits from a point of known location to provide your coordinates. The GPS stores latitude/longitude and converts them to northing/easting for construction purposes. I'm not exactly sure what you mean about all having to use the same one: you could have a guy setting a base up on site and another guy using a reference network and they should be getting roughly the same information. The network that we use often shows multiple reference stations with high accuracy. "Using the same one" does become more important for vertical information when you start talking about gravity drained systems.

Obviously that's pretty condensed but hopefully it helps.

As an FYI - Ol' @LongWayAround works in surveying so I'd say he's got a pretty good handle on this.

 

[kwackkillncrew]

I believe he is trying to say that that imagery and the platted lines have to be in the same horizontal datum/coordinate system. In of of those images it clearly looks to be some sort of shift in either the imagery or the property lines. Both sides seem to be off roughly the same amount.

Sent from my SM-G892A using Tapatalk

 

[riversidejeep]

I've seen them off by 50 yards, OnX is NOT a survey instrument.