Question
QUESTION: I have a row of Red Twig Dogwoods that are suddenly dripping a white milky goo all over the plants.  They are about 15 yrs old and I have never seen this before.  It might have happened before but I had a lawn service who trimmed them frequently.  This year they were very sparse until we went away 2-3  weeks ago.  We came home yesterday and the bushes are full and bushy but dripping white goo.  Any ideas what it is?  If this is normal, then when should they be trimmed?

ANSWER: Hi Sherry,
Thanx for your question.  Is milky substance foamy or liquidy?  If it is foamy, it is probably from spittle bugs and you can wash these off with a spray of the garden hose.  If it is liquidy, it could be the sap caused by borers.  You'll need to take some samples in to your local county extension agent.  If you'll give me your general location I can get the contact information for you.

Cornus alba, Cornus sanguinea and Cornus stolonifera types are all grown for winter stem colour. Pruning the dogwoods in early spring, gives the shrub plenty of time to generate masses of long straight cane-like stems for stunning colour effect in the following winter months.

Prune the Cornus sericea (redosier/redtwig dogwood) down to - or near ground level. Prune every stem down to this level. This hard pruning of the Dogwood removes all of the stems that were the attraction through the previous winter, but do not worry, for where you have carried out the pruning, many more stems will grow from the stumps left behind. These new young stems will produce brightly coloured stems throughout the following dormant season. If left un pruned, then the Dogwood would lose vigor, and the stem color would fade year after year.

Hard pruning is the way forward for this, and make sure that you prune early enough in the spring.

I hope this helps.
Tom



---------- FOLLOW-UP ----------

QUESTION: My husband says it is foamy, but when I touched it with my arm it looked like thick milk on my arm.  We are located in 60021, McHenry County, IL.  Last year I did see a lot of Japanese Beetles on the bushes, but the leaves aren't eaten.

Answer
Hi Sherry,
I'm thinking its a borer.  Please contact your county extension office and they'll probably ask you to bring in a sample.  This is a service out of your state's agricultural college.  I hope this helps.
Tom

http://web.extension.uiuc.edu/mchenry/