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Easter 2006 Dogwood near
full bloom.

Anthracnose
Tree Calendar
Julie's Trees
Facts at a Glance
Cornus florida
Planted Est. 1986
Planting height: 4'
Planting trunk: 1"
2006 Update
20-yr height: 20'
20-yr trunk: 30"
Mature Height: 15 to 30'
Spread: 15 to 20'
Growth rate: Moderate
Form: Layered, spreading
Flowers: White
Fall color: Wine red
Hardiness zone: 5 - 8
Culture: Partial sun
Best feature:
Flowers
Worst problem:
Anthracnose
Do over? No
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A Tree Grower's Diary White Flowering Dogwood
MY DOGWOOD AND ME: LIVING WITH ANTHRACNOSE
Photographs and text by Julie Walton Shaver
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Anthracnose Spots This tree was diagnosed with anthracnose in June
of 2004. The disease is not curable, but with special care and a lot of attention, it is possible to prolong the life of the
tree by many, many years.
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May 2004
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June 2004
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The fact that the dogwood had striped leaves meant it was stressed. So,
I was standing outside studying the tree when I noticed purple and brown spots and some dead twigs near the bottom.
I panicked!
A little research revealed that the tree was in the beginning stages of a disease called dogwood anthracnose. Since
the tree was already stressed from the lack of iron, it quickly became susceptible to other problems. Symptoms of anthracnose
include brown spots on the leaves, often bordered by a purple rim.
Dogwood trees often die from this disease, but with careful attention, the tree's life can be prolonged.
Affected branches must be removed -- but they must be pruned with care.
Here's what I did: Before each cut,
I dipped the pruners into a mixture of bleach and water -- 9 parts water to 1 part bleach -- and let the pruners soak for
1 to 2 minutes between cuts, then wiped away any remaining traces of wood. This helps prevent the disease from spreading to
healthy branches.
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As evident in these pictures, the tree seemed happy in May, then by June,
the leaves had changed. The area around the leaf veins was still green, but in between was turning yellow.
A little research revealed that this condition is called chlorosis, and it meant that the tree needed more iron, a nutrient
that is necessary for the production of chlorophyll in the leaves. Since chlorophyll is a source of food and energy for the
tree, these striped leaves, while beautiful in a sense, led me instinctively to think that something was wrong with my tree.
After a soil test revealed that the soil was slightly alkaline, I decided to add iron and sulphur to the soil. The sulphur
would lower the soil pH (dogwoods like acidic soil) and the iron would take care of the chlorosis.
Not long after adding Ironite to the soil, I learned it has arsenic in it. Yikes! Not exactly the kind of thing you want next
to your house. So, I had to find other ways to troubleshoot this tree's problems.

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UPDATE: May 2005
In June of 2004, I carefully and painstakingly pruned
off all the branches I could reach that showed signs of anthracnose using the specific pruning method described above.
In fall, I raked away as many of the dropped leaves as I could find, as early as I could get to it.

In spring of 2005, I applied Ironite to troubleshoot the cholorsis problem. Later, I learned that Ironite is dangerous
to children and pets, so I won't be using that again. There were still signs of yellow stripes in the leaves, but it
didn't look as bad in 2005 as it did in 2004.
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Amazing I think between the bone meal and the newspapers, which probably
added a decent shot of acid to the soil, this tree is happy now!

The black socks were NOT my idea.
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A Neverending Battle In spring of 2005, I applied bone meal
after having raked away and disposed of all the old mulch. I wanted to make sure the tree would not experience any problems
due to lack of moisture or competition with weeds so I put down six layers of sopping newspaper at the base of the tree, then
covered it with fresh mulch. A few weeks later, I fed the nearby arborvitae trees with Miracle-Gro, which probably also gave the dogwood tree a decent feeding.
In fall of 2005, I raked away all the leaves and disposed of them, and gave the tree another bit of bone meal.
I've never seen my dogwood look so full and healthy. After spotting the anthracnose in June of 2004, I thought the tree would
be looking a lot worse by now. It just goes to show what a little tender loving care can do. I did not see one spot of anthracnose
in 2005. Yay!

Starting Over
May 1, 2006, and here we are again, cleaning out the old
mulch, putting down a new layer of newspaper (after reading about Zack and Cody), adding more bone meal, checking for any
signs of anthracnose (none yet) and topping it all off with fresh mulch.

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New Mulch By evening, we were finished with our spring anthracnose plan . .
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. . . and still had time for more pictures.
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For Julie's detailed comments, see the Dogwood fact page
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