Hello, Colossal is perhaps the most common variety planted in the PNW. We do not have chestnut blight. Oregon Department of Agriculture maintains a control order against importation of Castanea material into OR. On the one hand this protects us from blight, on the other it also limits variety availability (to mostly Colossal). Chinese chestnuts (C. mollisima) and Chinese hybrids can have more blight resistance but typically have smaller nuts. There should soon be greater availability of these varieties as there has been recent effort to import new material to Oregon for tissue culture production. You may enjoy the attached article.