Chuck Denney: The white and pink blooms of the breath-taking dogwood serve as visual clue marking spring's much anticipated arrival. These stunning trees grow in all parts of Tennessee, with more than one hundred varieties statewide. Our mild weather is perfect for cultivating these delicate beauties.
Dr. Mark Windham: We have a good climate -- we have a long growing season. If you go very much farther south than us, it gets too hot for some dogwoods, so we're in a perfect place to do it. And Tennessee, of course, is the number one producer of dogwoods in the United States. There is an 80% chance, if a dogwood is sold in the United States, that that tree got its start in Tennessee.
Chuck Denney: Dr. Mark Windham is known as one of the 'dogwood docs' of UT AgResearch. He leads a team that cultivates new varieties of dogwoods in greenhouses on the UT Ag Campus and in test fields. This research is critical because dogwoods are such a huge money-maker for Tennessee's green industry, generating sales of some $40M a year. Given the importance of the dogwood to our agricultural economy, the UT AgResearch team works to protect these trees. Dogwoods have been threatened by a disease called anthracnose.
Dr. Windham: Dogwood anthracnose was the first major disease that we had to affect our nursery industry, and although it wasn't a very serious problem in the industry, it was a serious problem where we sold most of our trees.
Chuck Denney: Also, there is powdery mildew, a fungus that makes a tree look bad, like someone doused it with talcum powder.
Mark Windham: When powdery mildew showed up, there were millions of dogwoods that were being thrown away in our nursery industry because we didn't know what to do about it.
Chuck Denney: Dr. Windham and the UT AgResearch team developed dogwoods resistant to these diseases, especially in the case of powdery mildew. UT AgResearch then received patents on these dogwood varieties, with the scientific name of 'cornus Florida'.
Mark Windham: We have four trees that have been patented for powdery mildew resistance, and they are 'Appalachian Blush', 'Appalachian Mist', 'Appalachian Snow', and the most recent is 'Appalachian Joy'. The trees are all white, but they are very, very different in their horticultural characteristics. And so, working with the UT Research Foundation, we did disclosures; their patent attorney helped us through the process, and we were able to patent those trees. In addition to that, we also got a utility patent that patented the concept of powdery mildew resistance in cornus Florida. So, our trees are not only patented, but they are protected in the sense that other people cannot release trees that are resistant to powdery mildew.
Chuck Denney: Windham says these new varieties are selling well, and marketing surveys show that consumers are willing to pay more for a disease-resistant tree. UTIA even has marketing licenses for trees sold on the west coast and as far away as Japan. For Windham and his crew, there is still work to do to combat these dogwood diseases, but they are ready for the challenge.
Mark Windham: We are very optimistic about the future of cornus Florida. Now, of course, the holy grail, which is what we are working toward, would be a single tree that is resistant to both diseases -- one that is resistant both to dogwood anthracnose and to powdery mildew. We don't have that yet. But no one said that research is easy; its not, but that is out goal. And I am optimistic that with hard work and time, we'll reach it.
Chuck Denney: Meantime, there will be work at UTIA to keep these trees beautiful. UT researchers continue their efforts year around to make sure that future springs are dotted with blooms and color.