topic Re: LAS-data forestry analysis - How to separate different trees in 3D Questions

LAS-data forestry analysis - How to separate different trees

JonasJonzen — Wed, 12 Oct 2011 11:24:03 GMT

Im using ArcGis for forestry applications and have recently found out about LAS-data and the big possiblilites that comes with this data. I was wondering if there are any good ways of calculating the stem/ha from a LAS-file?

Thanks in advance,
Jonas

Re: LAS-data forestry analysis - How to separate different trees

JeffreySwain — Thu, 13 Oct 2011 12:09:10 GMT

With the LAS to multipoint input you can create a separate surface for just the trees. In the help documentation, there are codes for vegetation(3-5). If you LAS file has those codes then the surface can be built for the trees. You can generate another terrain based on the bare earth and then compare them for the heights.

Re: LAS-data forestry analysis - How to separate different trees

JonasJonzen — Thu, 13 Oct 2011 12:59:21 GMT

Thanks for your answer.
Yes, I have been able to do a separate file for the vegetation class. And if you look at the Multipoint file in Arc scene it is possible to visually see individual trees. But then Im lost how to do the rest and which tool to use. If it would be possible to create some shapes out of the tree tops it could be possible to figure out a way to see the individual trees?

Maybe im just cofused..I can attach a photo to explain how I mean later

Re: LAS-data forestry analysis - How to separate different trees

JeffreySwain — Fri, 14 Oct 2011 10:35:15 GMT

The natural next step is to create a Terrain from the different surfaces, with the Terrain the other steps can be performed to determine the volume of trees. Separating individual trees may prove difficult, but stand volume should work. Polygon Volume, Surface Volume and can be used to determine the stand volume.