The Ulmus 'Frontier', a hybrid elm cultivar, has been specifically developed to exhibit resistance to Dutch elm disease (DED). Here's an overview of its resistance characteristics:

• Resistance Level: The Ulmus 'Frontier' shows a moderate to high level of resistance to Dutch elm disease. This resistance is due to its hybrid nature, combining the Ulmus carpinifolia and Ulmus parvifolia species, which contribute traits that enhance its ability to withstand the disease.

• Research and Development: Various studies and breeding programs have concentrated on cultivating elm varieties that can resist DED. The 'Frontier' elm is a result of such efforts, and it is recognized for its ornamental value and disease resistance.

• Cultivation Benefits: While no elm is completely immune to DED, 'Frontier' offers a viable option for urban and landscape planting where disease pressure might otherwise pose a threat to less resistant elm varieties.

In summary, although ‘Frontier’ is not entirely resistant to Dutch elm disease, it has a significant level of tolerance compared to other elm types, making it a preferred choice for both aesthetic and practical purposes in regions affected by the disease. When considering tree planting, it's also beneficial to implement integrated pest management strategies to further protect against DED.