Remote Sensing and Weeds

Remote analysis of biological invasion and biogeochemical change

Gregory P. Asner and Peter M. Vitousek

More weeds, this time over to Hawaii for my favorite tree, Myrica faya (I believe it was recently renamed, because I learned it as M. faya and then was told there was a new name, but can't remember it). One of my favorites because the wood isn't super dense, and it's hackable with a machete when doing invasive species control.

Regardless, it's a nitrogen fixing invasive, and the Asner/Vitousek study looks at using foliar N as measured via AVIRIS to detect M. faya prior to it's domination of the canopy. It works, quite well. And for another note, they also found they could detect another invasive, a ginger (and not a fun thing to attempt to control), via water content measurements from AVIRIS- and it's an understory plant. This is a slight vindication for me, since I heard that something like this was possible from Greg in Hawaii, but when taking remote sensing back in Washington later, was told that sensing anything below the canopy wasn't possible. Awsome, it's in print.


This has me thinking: Scotch broom is another invasive species, nitrogen fixing, present in the west and up into BC and Alaska. While I don't think it makes it to the canopy, I wonder if you can detect it's presence via overstory N levels, especially since foliar N seems to be pretty low in most of our forests. The next review has a paper which also inspires that thought....