our botanist, Martin, settles down with a sagebrush and a selection of keys
Interestingly, when the leaves of different species are put into water and viewed with a UV light, they fluoresce differently. Not practical in the field, but it allows us to test our field IDs back in the office. Although sitting in a dark office lighting up tubes of sagebrush leaves does make other coworkers wonder...
The photo didn't come out as well as I hoped, but you can see that the left two tubes are fluorescing, and the rightmost isn't. Second from the right did fluoresce slightly.