Volunteer dogwood trees
I've owned a home in Wheaton for 40 yrs and over time birds and squirrels have deposited dogwood seeds in my hedgerows. They grew to various heights and lived 2-5 yrs. All succumbed due to some blight. However, over the past 8-15 yrs three of these "Volunteers" have defied the odds. They have been gnawed on by deer, shown signs of the crud (black spots, early leaf drop) and been fertilized by lots of dog pee and poo. Somehow they have survived and they are all currently in full bloom. Yeah! Is this unusual? Could I possibly have mutant trees? Would anyone from UMD be interested in coming out to inspect/take samples? Just asking.
You have demonstrated the principle of 'natural selection' in your landscape. The dogwoods with the best DNA have survived.
Dogwoods have been attacked in recent years by anthracnose (a fungus) and powdery mildew (also a fungus.) Fortunately, there is such a great genetic diversity in the wild population of dogwoods, that they have been able to produce so many berries with different traits that the good ones have successfully overcome the diseases (and in your case many other challenges) and survived.
So, your trees are not mutants, but winners!
Much research and hybridizing has been done to find and cultivate new 'varieties' or 'cultivars' of dogwoods that are resistant to the two fungi mentioned above. They are available on the market now. (Appalachian series is one.) You could contact nurseries and tell them about your dogwoods, so see if any are interested in ones that can overcome BOTH of the diseases.
Since this is actually a commercial question, you can contact Stanton Gill to see if he can recommend a production nursery that might be interested in your plants. His contact information is in the Staff Directory at the bottom of our homepage.
Thanks a bunch for your speedy replies with so much info.