Dawn Redwood Diseases

Dawn Redwood Characteristics

• Dawn redwood looks like an evergreen, but has deciduous needles. Green during the warm season, the thin leaves give the branches a feather-like look. As fall arrives, the leaves turn brilliant shades of yellow, orange, red or brown. The trunk is a reddish-brown when young, turning to a darker shade with shedding bark as it ages. A fast growing tree, the dawn redwood requires very little pruning, if any, to keep its naturally defined pyramidal shape.

What is Canker?

• Canker is an indented area of dead or decaying plant tissue on a tree stem or branch and can be caused by a variety of sources including lawn equipment damage, insects, environmental circumstances, bacteria and fungus. Some cankers are very obvious, while others may appear as a natural characteristic of the tree. Cankers on branches can cause the leaves to darken and shrivel, and infected bark is often discolored and weeping. If left unattended, cankers can destroy tree limbs, kill young trees and severely deform older ones.

Dealing with Canker

• To help stop the spread of the canker to other parts of the tree, or those nearby, remove any dead, dying or diseased branches as soon as they are identified. Any branch pruning should be done well beyond the obvious canker area to help remove any non-visible affected area surrounding the infection, and pruning should not be done during wet conditions, which may cause the canker to spread. Applying a small amount of fertilizer will help strengthen the tree, but take care to not over-fertilize; excess fertilization may speed the canker development. Once the canker has entered the trunk, however, pruning the limbs won’t stop the spread and the tree may not survive the infection. All of the pruning debris needs to be destroyed to help limit or stop the canker from spreading to other trees that may be in the area.

Tree Care

• Taking proper care of the tree can help prevent canker from setting in. Dawn redwood trees like full sun and well-drained soil. They are not particular about the soil type, prefer a more acidic pH and will accept overly moist conditions. With a limited tolerance for drought, dawn redwood should be watered regularly during dry periods. Ensuring trees are well spaced when planting will reduce the occurrence of stress, which in turn reduces the risk of disease. Crowded trees become susceptible to problems.