Insects and climate change are killing New Mexico’s trees
By Bryce Dix
April 24, 2025 at 5:40 AM MDT
A new state report out this week finds conifer tree deaths – including iconic species like the Ponderosa and Pinyon pine – doubled in New Mexico’s forests last year.
The New Mexico Forest Health Conditions 2024 report by the New Mexico Forestry Division, is based on aerial surveys over 14 million acres of state, private, tribal, and federal forests.
Key findings show 70,000 acres of conifer forests died in 2024 – up from 33,000 in the previous year. Statewide “defoliation” or the visible loss of needles and leaves rose a whooping 39%.
“A lot of what goes on with aerial surveying is both science as well as art,” said Victor Lucero, Forest Health Program coordinator for the agency. “Each tree takes on a different appearance as they're either defoliated or attacked by a bark beetle.”
There are several culprits for large swaths of trees turning brown or red. For example, over 248,800 acres were destroyed across New Mexico by the native Western Spruce Budworm, whose larvae rank among the most destructive defoliators of forests in the region.
The report finds a total of 406,000 acres have been damaged by insects, disease, and drought. Though, Lucero is quick to point out that things could be much worse.
“This is actually not a bad year,” Lucero said. “In 2023 there were five times the number of acres impacted by bark beetles.”
While various species of bark beetle also contributed, these bugs do play a crucial role in forest and woodland ecosystem health in New Mexico. Much like a prescribed burn or tree thinning, beetles clean up canopy by attacking unhealthy, stressed trees.
But this natural method of thinning can quickly become a problem as climate change fundamentally reshapes conditions in New Mexico’s forests. Warmer, drier weather creates the perfect storm for more severe and frequent insect outbreaks.
Similarly, burn scars proved to be a hotbed for insect activity.
The aftermath of the 2022 Calf Canyon/Hermit’s Peak Fire created ideal conditions for bark beetle outbreaks. On nearby National Forest land, Douglas fir beetles and fir engraver beetles went on to destroy 15,000 acres of mixed conifer forest that survived the fires.
“Whenever we look at a burn scar, obviously the exposed soil is exposed to solar radiation. It's hotter and the moisture is depleted quicker,” said Lucero. “Any stressor that is out in the landscape definitely predisposes trees to attack from bark beetles.”
Overall, 2024 was the second hottest year on record for the state and most of the western United States experienced a significant snow drought, resulting in early season warming. New Mexico itself saw a slight improvement from summer monsoon rain amidst decades of lingering mega drought conditions.
That has Lucero thinking hard about what New Mexico will look like as drought creeps over more forest in the next 10 to 20 years.
“We do have to manage our forests and woodlands for hotter and drier conditions, which means that there ultimately needs to be a closer look at the number of trees per unit area that actually can be sustained,” Lucero added.
The New Mexico Forest Health Conditions 2024 report by the New Mexico Forestry Division, is based on aerial surveys over 14 million acres of state, private, tribal, and federal forests.
Key findings show 70,000 acres of conifer forests died in 2024 – up from 33,000 in the previous year. Statewide “defoliation” or the visible loss of needles and leaves rose a whooping 39%.
“A lot of what goes on with aerial surveying is both science as well as art,” said Victor Lucero, Forest Health Program coordinator for the agency. “Each tree takes on a different appearance as they're either defoliated or attacked by a bark beetle.”
There are several culprits for large swaths of trees turning brown or red. For example, over 248,800 acres were destroyed across New Mexico by the native Western Spruce Budworm, whose larvae rank among the most destructive defoliators of forests in the region.
The report finds a total of 406,000 acres have been damaged by insects, disease, and drought. Though, Lucero is quick to point out that things could be much worse.
“This is actually not a bad year,” Lucero said. “In 2023 there were five times the number of acres impacted by bark beetles.”
While various species of bark beetle also contributed, these bugs do play a crucial role in forest and woodland ecosystem health in New Mexico. Much like a prescribed burn or tree thinning, beetles clean up canopy by attacking unhealthy, stressed trees.
But this natural method of thinning can quickly become a problem as climate change fundamentally reshapes conditions in New Mexico’s forests. Warmer, drier weather creates the perfect storm for more severe and frequent insect outbreaks.
Similarly, burn scars proved to be a hotbed for insect activity.
The aftermath of the 2022 Calf Canyon/Hermit’s Peak Fire created ideal conditions for bark beetle outbreaks. On nearby National Forest land, Douglas fir beetles and fir engraver beetles went on to destroy 15,000 acres of mixed conifer forest that survived the fires.
“Whenever we look at a burn scar, obviously the exposed soil is exposed to solar radiation. It's hotter and the moisture is depleted quicker,” said Lucero. “Any stressor that is out in the landscape definitely predisposes trees to attack from bark beetles.”
Overall, 2024 was the second hottest year on record for the state and most of the western United States experienced a significant snow drought, resulting in early season warming. New Mexico itself saw a slight improvement from summer monsoon rain amidst decades of lingering mega drought conditions.
That has Lucero thinking hard about what New Mexico will look like as drought creeps over more forest in the next 10 to 20 years.
“We do have to manage our forests and woodlands for hotter and drier conditions, which means that there ultimately needs to be a closer look at the number of trees per unit area that actually can be sustained,” Lucero added.