Valley Forge Elm
Valley Forge is a true American elm introduction from U.S. National Arboretum with outstanding DED resistance. This tree has a lot of well-earned notoriety for being hard to manage in the nursery and as a young tree in the landscape! Once it gets into larger stem caliper ranges it seems to “settle down” a little and take on a more manageable form and habit. If you are interested in trying this tree, be ready to devote enough time to pruning it for long-term health and branch structure. Young Valley Forge (less than 10in DBH) should be pruned at least every two years for the first 10 to 12 years. It is reported to be 96% resistant to DED in inoculation studies and appears to be fully hardy in USDA Hardiness Zone 4. Also note susceptibility to Japanese beetle feeding, noted above under Princeton.