Using ArcPad and GPS Offsets For Mapping Vegetation in Lakes_Confirmed Presentation

Site Archive
You are viewing a static copy of the 2009 Sunriver Conference website archived on December 11, 2013. To view current Northwest GIS User Group events and news, visit

Mobile GIS users are frequently confronted with difficult mapping situations. Mapping the pond lilies in Cheadle Lake, Oregon is an example of mapping project requiring the use of a laser rangefinder, a Pocket PC running ArcPad, and a sub-meter GPS unit. Mapping pond lilies in Cheadle Lake had a direct bearing on jurisdiction of the lake relative to the City of Lebanon and their future plans for turning the lake into a warm water fishing destination. Pond lilies have roots in solid ground and therefore define their location as land ownership. Normally, a lake would be owned up to the high water mark by the State of Oregon.

Mapping vegetation in a lake can be very difficult. Using is boat is feasible, but time consuming, expensive, and difficult. By taking offset GPS points with ArcPad, the process can be greatly simplified and the time required to do the mapping can be significantly reduced.

The project involved using a laser rangefinder to shoot the pond lilies which are barely visible in the water. All offset shots were taken while standing on the shoreline around the lake and from a island in the lake.

Jon Aschenbach

Jon Aschenbach is president of Resource Supply, LLC in Tigard, Oregon. He has extensive experience working with resource grade GPS units and the ArcPad mobile GIS software. Jon has taught several seminars including “Learn ArcPad in One Day”, “Professional Timber Cruising”, “GPS in Forestry”, and “Practical Application of New Technology in Forestry”.

Jon’s forestry career started in 1973 as a reforestation forester for Crown Zellerbach Corporation. After twelve years with Crown Zellerbach, Jon was Vice President of Atterbury Consultants for 23 years. His present company, Resource Supply LLC was formed in 2008.

Your rating: None Average: 3.3 (4 votes)