In 2008 the Virginia Geographic Information Network (VGIN), the Virginia Department of Transportation and the Virginia Department of Forestry partnered with USDA to acquire leaf-on, color-infrared, 1-meter resolution, digital imagery for all of Virginia. VGIN has made compressed county mosaics available for download here.
In the first versions of the JPEG2000 mosaics the infrared band (band 4) did not display properly in ArcMap 9.3.x. This is a known bug for certain versions of JPEG2000 headers. USDA has revised the header to allow proper display for most of the Virginia mosaics. VGIN has recently made the new versions (identified as Countyname.v6) on the VGIN download page. If you are using the old mosaics you may wish to update to the new version. If v6 is not appended to the county name only the uncorrected version is available at this time.
VGIN has also received from USDA the NAIP 2008 imagery in quarter quad tiles in GeoTIFF format. If you have a need for uncompressed imagery for specific areas feel free to contact John Scrivani for access to this public domain imagery.
An excellent example of the uses of leaf-on-infrared imagery is the Urban Tree Canopy Analysis being done for various communities by the Virginia Department of Forestry and the Virginia Geospatial Extension (VGEP) at Virginia Tech.