For the past 15 years, more than 2.5 million acres, or 90 percent, of Pinyon pine and juniper trees have died in the American Southwest. Researchers believe a combination of drought and mountain pine beetle attacks are the primary forces for the loss with possible additional ecological disruption. Scientists contend the dieback represents the last trees that can not only protect a fragile ecosystem in this region but also nourish plant and animal species. Pinyon pines and junipers also prevent soil erosion due to the wind. Blowing dust from eroded hills has been covering the snowpack, causing less reflectivity, increasing heat, advancing snowmelt and reducing water supplies in the Colorado River basin. The Pinyon pine and juniper are naturally drought resistant and the last bastion to hold soils in place. Fastcast: Daybreak showers.