Your SlideShare is downloading. ×
Tree Diseases
Upcoming SlideShare
Loading in...5

Thanks for flagging this SlideShare!

Oops! An error has occurred.


Saving this for later?

Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime - even offline.

Text the download link to your phone

Standard text messaging rates apply

Tree Diseases


Published on

Published in: Technology, Self Improvement

  • Be the first to comment

  • Be the first to like this

No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

No notes for slide


  • 1. Urban Forestry Plant: Elm Tree Urban Forestry
  • 2. Urban forestry
    • The care and management of urban forests, (tree populations in urban settings) for the purpose of improving the urban environment
    • Most urban trees are non-native and selected for particular aesthetic qualities
  • 3. Elm Tree
    • The American or White elm is the largest species of elm.  Usually over 100ft high.
    • Due to its graceful form and size, it was an extremely popular urban tree before the spread of Dutch elm disease. 
    • Once found mostly in eastern North America, remaining populations of mature American elms are concentrated in the American Midwest and Canadian Prairies.   
  • 4. Dutch Elm Disease
    • Dutch elm disease (or DED) is caused by a fungus. After the disease is contracted, spores rapidly reproduce and spread toxins throughout the tree.
    • Fungus is spread by the elm beetle
    • The fungus blocks the vascular system of the tree preventing water and minerals from reaching the branches and leaves.
    • The leaves wilt and eventually the tree dies.
    • In Washington, DC, the disease has killed over 25,000 elms since 1950 with only 8,200 elms presently remaining on city streets.
  • 5. Combating Elm Disease
    • Because Elms are such an important urban species, much $ and effort goes into keeping them alive
    • Fungicides are injected into the root flare
    • Disease resistant elms are often planted as replacement trees. Washington DC tries to maintain the annual DED loss at below 2% of the remaining elm population.
  • 6. Anthracnose
    • Fungus that attacks hardwood shade trees
    • Kills the buds, damages the leaves and causes premature leaf drop
    • Over time weakens the tree and makes it susceptible to borers and other pest damage
    • Fungus overwinters in leaves on the ground.
    • Remove all fallen leaves and dispose of them
    • Treat by using fungicides
    • Tree on right was treated
  • 7. Emerald Ash Borer
    • Asian Beetle that bores under the bark of ash trees & lays eggs.
    • The larva hatch and eat the cambium layer of the tree
    • Has killed millions of trees around the great lakes and is moving south into WV, PA, & VA.
    • Treatment is expensive and requires trained applicators.
  • 8. Cankers
    • Caused by fungus penetration of the bark
    • Treatment – pruning below affected area
    • Sterilize tools afterwards so as not to spread the disease.
  • 9. Rust Diseases
    • Cedar Apple Rust is biggest problem
    • Affects crab apple trees and junipers
    • Lives part of life cycle on each tree
    • Destroy galls before April when they spread by spores
    • Don’t grow cedars and apples close together
    • Select resistant plants
  • 10. Galls
    • Growths that form on the leaves or stems of plants
    • Can be caused by insects or viruses
    • Rarely affect the overall health of a tree
    • No treatment is required