Satellite-Based Change Recognition and Tracking


Monitoring Gypsy Moth defoliation in near real time

By late 2012, forest health monitors in western New York and Pennsylvania knew that they were about to experience a severe outbreak of the non-native Gypsy Moth. Surveys showed an unusually high density of egg masses on the branches and trunks of trees, but neither egg... read more »

Hail devastates corn and soybean fields in Nebraska and Iowa during June of 2014 ForWarn EFETAC Steve Norman

Massive hailstorm destroys Midwestern crops

During the first week of June 2014, hail caused significant damage to corn and soybean fields in eastern Nebraska and western Iowa. By June 9th, ForWarn's all-lands product was beginning to show the losses that these storms inflicted across multiple counties despite... read more »

Drought, beetles and fire in Colorado

Since 2004, southwestern Colorado's Englemann spruce forests have experienced a severe outbreak of spruce beetles (Dendroctonus rufipennis). Such outbreaks occur episodically, multiple times per century (Anderson et al. 2010). Early research in northern Colorado linked a... read more »

Forest Tent Caterpillar defoliation along Conoho Creek

Defoliation in NC's Roanoke River Bottomland Forests

The Forest Tent Caterpillar (Malacosoma disstria) is a widespread native defoliator of deciduous forests in the Eastern US. While host trees differ regionally, the insect prefers sweet gum (Liquidambar styraciflua), tupelo gum, black gum (Nyssa spp.) and species of oak (... read more »

Spring defoliations emerge like measles during 2010; Image: Steve Norman, USFS.

Defoliation on the bayou

Spring often brings defoliating insects to the forests of Louisiana. In this image from early May 2010, defoliations from forest tent caterpillars and baldcypress leafrollers create an erupting "measles-like" pattern. Note the subtle differences in severity outward from... read more »

Pandora Moths on the Kaibab National Forest

Pandora Moth defoliation returns to the Kaibab

The Pandora Moth (Coloradia pandora) is a native defoliator of ponderosa, Jeffrey and lodgepole pine trees of the Western US. During most years, populations and defoliation is minor, but periodic outbreaks cause widespread defoliation (Speer and others 2001). The... read more »

Hemlock death transforms Appalachian forests

Across the Southern Appalachians, Eastern Hemlock has long created an important ecological niche. As these trees are evergreen, they provide year-long cover for wildlife and they cool riparian areas where they tend to grow. Since the mid 2000s, these forests have been... read more »

ForWarn's median date of start of greenup

The typical start of greenup in natural vegetation

The start of the annual growing season is among the most important climate-sensitive measures that Land Surface Phenology (LSP) products like ForWarn can provide. Warm temperatures can accelerate bud burst, and this can increase exposure to damaging spring frosts, as it... read more »

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ForWarn provides near-real-time tracking of vegetation changes across landscapes in the United States. Useful for both monitoring disturbance events as well as year-to-year variability, derived products can also be used to develop insights into seasonal and inter-annual dynamics.

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Forest Change Assessment Viewer

The Forest Change Assessment Viewer provides a vegetation change recognition and tracking system for ForWarn that uses high-frequency, moderate resolution satellite data.

Recent News

11/23/2015 - 13:49
ForWarn team members attended the 2015 Association for Fire Ecology Meeting in San Antonio, TX in November 2015 to present research on long-term monitoring based on ForWarn’s NDVI products. You can...
09/02/2015 - 10:09
ForWarn’s viewer was designed to let users recognize and interpret change, and interpretation is supported by ancillary map layers from a variety of sources. Until recently, change caused by fuels...
05/14/2015 - 16:25
The Fire Learning Network (FLN) brings managers and scientists together to address common problems and solutions related to wildland fire.