You can always cross your fingers but the destruction was so widespread that it's unlikely that any indigenous immunity existed. If it did we would certainly know by now.
But every surviving chestnut might have resistances to something else, like other diseases, stressors or environmental conditions, and we are going to want to cross breed the resistant plants with every other chestnut we can get our hands on in order to create a robust population. Otherwise you end up planting a bunch of trees that die in the first drought, ice storm, or are only happy in one section of the former range.
But every surviving chestnut might have resistances to something else, like other diseases, stressors or environmental conditions, and we are going to want to cross breed the resistant plants with every other chestnut we can get our hands on in order to create a robust population. Otherwise you end up planting a bunch of trees that die in the first drought, ice storm, or are only happy in one section of the former range.