Tristan Clum

Earth Notes Host

Tristan began his career in public radio in 1988 as a reggae show host and programming assistant at KNMS-FM in Las Cruces, New Mexico.  In the decade that followed, he worked as a public television producer and as an assignment editor for the Albuquerque NBC affiliate.  Tristan graduated from the University of New Mexico in 1992 with a degree in political science.  He has won numerous awards for reporting and anchoring from both the Arizona and the New Mexico Associated Press.  He hosts KNAU's weekly program Earth Notes.

When summer’s flashy circus of wildflowers has passed and the last browned autumn leaf has fallen, an eye looking for signs of plant life is left with the conifers, those stalwart trees that stay green all year long.

Conifers do drop their needles and replace them with new ones—just not all at once. Their ability to photosynthesize all year long gives them a built-in advantage in living in places with a relatively short warm season. So does their natural chemical antifreeze, which prevents needles from freezing even in frigid conditions.

When it comes to controlling the many non-native, invasive plants in northern Arizona, weed warriors call on every tactic in the book. As they seek to minimize the spread of a weed called diffuse knapweed, they’re turning to a tiny ally: a weevil that loves to eat knapweed seeds.

Diffuse knapweed is a low-growing shrub that originated on the Russian steppes. Since the 1980's, it’s taken over roadsides and pastures in the region. It’s a heavy seed producer and a tough competitor against native plants.