KNAU and Arizona News
5:00 am
Mon April 28, 2014

Grand Canyon Continues to Battle Harmful Invasive Plant Species

Next month, officials at the Grand Canyon will continue a program of ridding many areas of invasive plant species. As Arizona Public Radio’s Ryan Heinsius reports, the goal is to protect native habitats even in the most heavily visited areas.

Invasive tamarisk trees in the Grand Canyon
Credit blog.audubonguides.com, photo by Lisa Densmore


For several years, managers at Grand Canyon National Park have been attempting to eradicate species that were either intentionally or accidently introduced to the area. While much of that effort has focused on the inner canyon, recently the South Rim has also undergone the process.

Lori Makarick is the vegetation program manager at Grand Canyon National Park.

“The mission is the same for the Park Service whether it’s in the developed areas or the more remote backcountry areas, and that is to preserve and protect these ecosystems and all of the components … We don’t just write off the developed area because there’s not as much habitat.”

Park officials have identified several non-native species like the tamarisk and the silverleaf nightshade that can only be removed with chemicals. As a result, the park is using several herbicides rated low in toxicity.

Makarick says the program isn’t designed to return the Grand Canyon to a completely natural state. Instead, it counters the most harmful effects of invaders like animal-habitat destruction and wildfire.

“Because of the number of non-native plant species we have in the park — just over 200 — we really target just the ones that have the ability to pose a threat to the park’s ecosystems.”

This year’s removal efforts will begin next month and continue through the fall.