Thursday, October 25, 2007

Dying Leyland Cypress

Q. Why is my Leyland cypress turning brown?
A: This question seems to be growing more and more common. Leyland cypress is a relatively inexpensive, fast growing conifer used for screens and specimen plantings. I have a long row of them in my own landscape and have had no problems thus far and they are about 10 years old. Nevertheless, they do have several problems that are making them less and less desirable in our area. The most common problems found on this plant are fungal tip blights & cankers and occasional bagworms. This year the cankers are by far the most common problem.
Seiridium canker is becoming a serious problem of Leyland cypress. This disease may kill young shoots, older branches and in some cases entire trees. Bleeding cankers are often observed on the trunks of infected trees. Trees that are stressed by transplant shock, drought and/or high or low temperature may be more likely to be infected by this disease.
Botryosphaeria canker is usually found on established Leyland cypress. Branch dieback is often the first symptom observed on diseased cypress. Again, bleeding cankers may be observed on the trunk of infected trees but is much more common with Seiridium canker. If the canker girdles the trunk the entire tree will likely die. This fungus, like many other fungi that cause cankers, is opportunistic and attacks plants weakened by drought stress, site problems, pruning wounds, insect damage or construction damage. This disease is particularly damaging to those trees suffering from drought and heat-related stress like what we have experienced this summer. Even though drought conditions can exacerbate this disease the problem can also be worsened by poorly drained soils.
Dr. Jim Jacobi, Extension Plant Pathologist says, “These canker diseases have similar symptoms of scattered dead branches throughout the canopy. However, this year Botryosphaeria canker is the more common of the two canker diseases of Leyland cypress. Drought this year and last year have greatly increased problems with canker diseases. Planting in good well drained soil, mulching and watering during dry weather are the key factors to growing healthy Leyland cypress. Fungicides are of little help with these diseases.”
For detailed information on diseases of Leyland Cypress check out the Extension publication at this web address:


unknown said...

my tree looks exactly the same. Seemed to happened when I overwatered in the summer, came on all of a sudden.

Will it recover?

(is it pH sensitive in the soil to other plants nearby)

TN Nursury said...

Anyone who wants to grow healthy plants should know that location is one of the most important factors that governs successful growth of plants. Most people buy a plant, go out into the garden, dig a hole somewhere, and place the plant in the soil: and when the plant fails to grow, they blame the nursery or soil. Site selection is vital if you want your plants to grow and thrive. Choosing the best site can save a lot of frustration and headaches.
quick growing trees

Anal Wood said...

Excellent writing about Dying Leyland Cypress", it is actually useful for me. keep writing and happy blogging.

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