Hi...I have an older white dogwood in my yard in Qualicum and everyone says it is probably infested with Anthracnose. I just sprayed it with copper spray but know there is much more to do due to the problem. My questions: l. Am I wise to cut it down? 2. Could I put a dogwood satomi in where it is removed?Do you recommend this type of dogwood?Would it be prone to disease to put the new one in the old space? 3. Should I be spraying other dogwoods in the yard to prevent disease? I am rather at a standstill knowing what to do. It is a big tree near the front of the house and would miss having one there. Thank you...Leigh
Hello Leigh There are several dogwoods available that are semi-resistant to Dogwood anthracnose. A common cultivar used in the lower mainland of BC is China Girl or the Cornus kousa hybrid 'Celestial'. you may also want to try the Cornus kousa hybrid 'Constelation' It would be a shame to cut down the dogwood . Spray regularly with copper all the dogwwods in your yard. it is part of being in a coastal or maritime climate that certain species will be more affected by disease than others. You should also go into a regular feeding programme foir the dogwoods. a granular rose food with balanced trace elements should help bring back the tree into health. One handfull for every 2-3ft of tree height every 6-8 weeks starting in march so March, May, July and September should do it for the fertilizing. if the tree is in the lawn it is essential that you get the fetilizer below trhe grass roots so that the dogwood gets it not the lawn. Dig some small holes out at the drip line of the tree about 8inches deep. usually I use a mallet and a piece of rebar. add one handful into the hole. repeat digging the holes as is necessary to fulfill the one handful for every 2-3 feet of tree height formula. The theory is just like us the tree needs a balanced diet with trace elements and major nutrients to be healthy. if not just like some of us it ends up grouchy and grumbly!! hope this helps Pierrot
Constellation is a registered trademark. The cultivar is 'Rutcan'. Do not fertilize without sampling your soil and having it analyzed. Take samples of diseased parts to an independent garden center or other source you trust for commentary on what may be wrong. Search internet for "dogwood disease" and look at plant disease books for more information. VanDusen Botanical Display Garden on Oak Street, Vancouver has an attended horticultural library that is open to the public. There is also a collection in the UBC offices.
Ron, are you hearing any reports in the Pacific Northwest of this pathogen overwintering on Cornus nuttallii and Cornus florida with the resultant visible cankers in the branches and later on the trunks? I was just wondering if this form is the same as the Discula destructiva found on the East Coast. The symptoms as described and the photos by WSU are closer to what we see on many of our Ash here in the Spring - Gnomoniella fraxini (Discula fraxinea). Dogwood Anthracnose factsheet Dogwood Anthracnose ANTHRACNOSE DISEASES OF TREES Jim
Sorry Ron, I did not mean to single you out or put you on the spot. If you hear of anything later on let me know. Jim
