 Early studies on hypovirulence showed that less virulent strains of the chestnut blight produced less oxalic acid when attacking the cambium.The transgenic trees have blight resistance either equal to or surpassing that of Chinese chestnuts.In 2013, SUNY ESF had over 100 individual events being tested, with more than 400 slated to be in the field or in the lab for various assay tests in the next several years and more than 1,000 trees growing in several field sites in 2014.