First of all the sun in most likely secondary. Second, Cornus florida
dogwoods are understory trees and prefer understory sunlight. Second
regardless of the "wound" you should treat the system. can you take a
picture of the tree and the wound. here are some of the recommended
treatments for your tree system. A picture of the wound would be great!
1st requirement is partial shade. Which type dogwood is it?
2nd fertilizing / mulching.
The first step in proper fert. is "feeding" and stimulating the soil
micros, that in return, alter the chemical elements such as iron, nitrogen,
boron and so on so they are in a form that the tree can absorb. Also the
mycorrhizae greatly facilitate the absorption of elements dissolved in
water. The fungi portion of the composite organ rely on composted wood as
its substrate. In fact in a forest, nurse logs are the substrate for the
base of the food web, the mycorrhizal fungi. Anyway, I have specific
instructions for mulching here:
After mulching organic fertilizer, I recommend organic, because some
products such as "Plant Tone" has about 56 or 16 essential elements within.
I do not find pleasure pushing products. However, I am recommending to
fertilize with as many of the essential elements you can get. I would also
cut the recommended dosage on product in half. The element that is lacking
will be the element factor.
If you read the label there are listed the elements the product contain.
There are 17 essential elements known of:
C; H; N; O; P; K; S; Mg; Ni; Fe; Ca; Zn; Mo; Mn; B; Cl; Cu
It used to be 16 essential elements but with techno equipment at Penn State
they recognize Ni as an essential element.
Also the organic fertilizer helps feed the micros.
Fertilize article: http://www.treedictionary.com/DICT2003/shigo/RHIZO.html
Its also winter time and a good article would be:
maybe the tree was planted too deep. That can create such symptoms.
If you are going to water the tree, just water it enough to moisten the
absorbing roots which are in the upper 4" of soil most of the time.
Do not water at the trunk but away from the trunk.
If you decide to prune your tree I would recommend this first.
The big thing for your dogwood is soil management and shade.
Please get me some pictures of wound, where the trunk meets the soil, and
some of the branches. Then I can guide you better.
John A. Keslick, Jr.
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