bunny by wanghonghx


   Woodland Park and the
    Olmstead Brothers

Woodland park was included in the
comprehensive parks plan created for
Seattle by the landscape architects the
Olmsted Brothers.
– Formal plantings
– Problematic monocultures
                  Species Found:
Big leaf maple
Western red cedar
Lombardy poplar
horse chestnut* (lots of this)
Alaska yellow cedar
Witch hazel
Chinese pines
Port Orford cedar
Mountain ash
        Problems Found:
Noxious weeds
Tent caterpillars
Stressed trees in off leash dog park
Dutch elm disease
Dogwood anthracnose
Spruce aphids
         Noxious Weeds
Non-native plants that grow aggressively,
lack natural enemies, and resist control

They destroy native plants and wildlife
habitat, damage recreation areas, lower
land values and may even poison humans
and livestock .
   State Weed Control Law
Under this law land owners, both private
and public, are required to control or
eradicate noxious weeds on their land.

Noxious weeds that are problematic at
Woodland Park include:
– Garlic Mustard (Alliaria petiolata)
– Giant Hogweed (Heraleum mantegazzianum)
Giant Hogweed
The Best Management Practices
Preventing infestations by monitoring and
removing pioneering plants is the best control
Hand Pulling works well but must be continued
until the seed bank is exhausted
Replace with native species after removal
There are no biological control agents currently
Chemical Control is the most economical choice
for such a large area. Spray with:
– Roundup (Glyphosate)
– Brush Be Gone (Triclopyr)
Hazard Trees

 Aesthetic Damage
  Level…. Reached?
 Old needles brown

 Tap test yielded
  many aphids!
             Spruces in trouble!

•   Stress cones

                         •Whole stand in decline
                         •Weeping sap at base
                         •Unknown root disease
          Spruce aphid control

•   Merit (UW Campus)
•   Horticultural Oil
•   Azadirachtin
•   Imidicloprid
Elm Trees
        Caretakers of Woodland
         Park are concerned about
         Dutch Elm Disease
        Symptoms and Signs:
             -Wilting leaves
             -Flagging and branch
             -Dark streaks of
             discoloration in the
                        Elms Cont.
   To keep track of the Elm
    trees, Elms are tagged
   In order to keep the Elms
    healthy, they are injected
    with Dutch Trig once a
   Healthy Elms keep the
    park looking lush and
   If already infected, pruning
    the tree and sanitation
    around the tree will help to
    reduce insect vectors
   Also insecticides reduce
    insect vectors
   Dogwood Anthracnose is
    another problem that occurs
    Symptoms and Signs:
    -Irregularly shaped brown spots
     or blotches on leaves
    -Leaf loss, twig die back, dead
    -Fruiting bodies(sign of fungus)
   Possible Solutions:
        -Plant resistant species
        -Plant tree in a location
         with good aeration and
         not too much shade
        -Avoid wetting foliage
        -Rake fallen foliage
Dogwoods Cont.
          Possible Solutions:
               -Fungicides may be
Tent Caterpillars
            Tent caterpillars eat all the
             leaves on one branch, then
             move on to the next
            One tent can destroy up to
             20% of the foliage on a small
            The caterpillars eventually split
             up into smaller groups and
             feast on several branches at
Tent Caterpillars Cont.

               Control:
                -Pick the caterpillars off the
                -Destroy their tents
                -Spray with Bt
              Off-leash Dog Park
   Traffic
    Small area with many
    people and dogs
   Erosion
    Park on a hill and soil
   Concentrated Urine
    Effects on trees?
            Off-leash Dog Park
   Tree Decline
    Signs indicate root
        IPM Recommendations

   Mostly Cultural

   Some Chemical

   One Biological
    Improve tree health and avoid
          injury to trees

   Move off-leash area away from trees to flat,
    grassy area
   Stop spraying herbicides at bases of trees to
    control grass
   Instead, remove grass from around tree bases
    and mulch
          Mulch Very Important!
   Prevents mechanical and
    chemical injury (no
    Roundup at tree bases)

   Supresses weeds near tree
   Reduces water loss
   Adds nutrients
   Insulates roots from extreme
        Improve Tree Health …
   Plant understory to increase biodiversity, thus
    reducing pests and disease
       (and will beautify the park!)

   Water trees in summer during dry, hot weather
         Improve Tree Health …
   Protective fencing
    around newly planted
    trees, shrubs, and beds
    to discourage vandals
               Invasive Weeds

   Continue current methods of control for giant
    hogweed and garlic mustard

   Minor Himalayan blackberry areas – remove
    them before a major problem!
        Improve Tree Health …
   When Trees die from a disease, replace with
    different species or resistant variety
              Pests and Diseases
   Dutch Elm Disease
    Continue with current preventative program

   Dogwood Anthracnose
    Sanitation – rake up or prune off and dead and
    infected plant parts and remove from site
    If trees die, replace with resistant Asian dogwoods
              Pests and Diseases

   Tent Caterpillars
       Prune out tents and remove
                Pests and Diseases
   Spruce Aphids
       Spray a Horticultural Oil
        in Winter
A major pest!
Vandalism and litter
                     People …
   Report vandalism to
    police and request more
    police presence

   Close and gate off
    parking lots during non-
    daylight hours
                       People …
   A major help!
   Part of solution
                      People …
   Involve the
    neighborhood in
    improvement projects to
    save $ and instill sense
    of responsibility for the
    park and the trees
                   People …

   Volunteer naturalists to increase official
    presence in park and increase stewardship

   Interpretive signs to increase appreciation and
    educate the public
   Bobbitt, Van M., A.L. Antonelli, C.R. Foss, Ray Davidson, R.S. Byther, and
    R.R. Maleike. 1996. Pacific Northwest Landscape Integrated Pest
    Management (IPM): culture of key tress and shrubs and problem diagnostic
    and management options. Misc. Pub. 0201. Washington State University,
    Puyallup. 7612 Pioneer Way E., Puyallup, WA 98371
   Byther, R.S., C.R. Foss, A.L. Antonelli, R.R. Maleike, and Van M. Bobbitt.
    1996. Landscape plant problems. Washington State University, Puyallup.
    7612 Pioneer Way E., Puyallup, WA 98371
   Dreistadt, S.H., J.K. Clark, and Mary L. Flint. 1994. Pests of landscape
    trees and shrubs. Division of Agriculture and Natural Resources. University
    of California Publications. Oakland, CA.
   http://www.cityofseattle.net/parks/parkspaces/woodland.htm
   http://www.graffiti.org/seattle/seattle_12.html
   http://www.cfr.washington.edu/classes.uhf.451/PATHLECTURES.html

To top