Transcript Urban Weed Management - - Marion Soil and Water

Urban Weed Management
Developed by Pringle Creek
Watershed Council
Salem, Oregon
Presentation overview
• Definition of “weeds”
• Weed impacts
• Ways to identify and control
common invasive plants
• How to tackle weeds in your yard
• Resources for additional help
What is considered a weed?
• Any plant growing where it is not
wanted.
• Invasive and noxious weeds are the
most troublesome.
– Rapidly dominate the site
– Very difficult to control
Noxious Weeds in Oregon
• Landowners are responsible for controlling
the spread of noxious weeds on their
property
• Class A – worst; Class B – not as bad
Class “A” Weeds
Class “B” Weeds
Weed impacts
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Out-compete other plants for water, nutrients, and sun
Costly and difficult to control
Loss of wildlife and fish habitat; yard space
Some are toxic to people
and animals
Decrease property value
Increase erosion
Can take over
recreational areas
Minimize land uses
Spread rapidly
How do weeds spread?
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Humans
Pets
Wildlife
Water
Wind
Vehicles
Machinery
“Wildflower” mixes
We plant them
Soil disturbance
Weed Management
Prevention is the most effective practice of all!
• Buy clean seed for wildflowers or
lawns; don’t plant weeds!
• Clean yard equipment before using it in
another area
• Control weeds along streams
• Use mulch materials
or weed mats
• Pull weeds early –
before they go to seed!
Control Methods
Mechanical
• Mowing, hand pulling, burning, solarizing
Cultural
• Shading, site preparation, plant
appropriate competitive vegetation
Biological
• Parasites, predators, and pathogens;
typically a slow process
Chemical
• Often requires repeated application; can
be sprayed, wiped or painted onto leaves
or stumps; usually most effective in fall;
USE ACCORDING TO LABEL
English Ivy (Hedera helix)
Perennial
Woody evergreen vine
Reproduces by seed and
roots
Can kill trees!
Berries are poisonous to most
wildlife. Starlings love them!
Control methods:
hand pull or roll up vines
cut stems on vines in trees &
pull away lower vines from trunk
apply herbicides (requires
repeated application due to waxy
leaves)
Himalayan Blackberry (Rubus discolor)
Perennial
Deciduous to partially
evergreen
Reproduces by seed and
roots
Doesn’t grow as well in
shade
Control:
mow (at ground level) repeatedly
dig or pull up root crowns
deep shade from larger trees
apply herbicides in the fall to leaves
or cut stumps
Bull Thistle (Cirsium vulgare)
Biennial
2-5 feet tall
Flowers purple JulySeptember
Reproduces by seed
Seed can be viable for
10 years
Control:
hand pull
cut or mow before going to seed
apply herbicides in late fall or
early spring
Canada Thistle (Cirsium arvense)
Perennial
Flowers light pink-purple
Grows 1-4 feet tall
Has deep horizontal roots
Reproduces through
creeping roots, some seed
Control:
pull by hand (small plants)
apply herbicides; spot-spraying
young plants is very effective
Japanese Knotweed (Polygonum cuspidatum)
Perennial
Can grow up to 12 feet
tall
Hollow, bamboo-like
stems
Long creeping roots
Dies back in winter
Control:
Cut close to ground regularly (every
2 weeks during growing season)*
dig (small plants and surface roots)
apply herbicides to leaves & stems in
the summer or early fall
*be sure to properly dispose of all plant material
Poison Hemlock (Conium maculatum)
Biennial
Grows to 10 feet tall
Tiny white flowers &
purple-mottled stems
All parts of plant are
highly poisonous (if
eaten)
Reproduces by seed
Control:
hand pull or dig* (small plants)
apply herbicides in early spring or late fall
*be sure to wear gloves & properly dispose of all plant
material
Scotch Broom (Cytisus scoparius)
Perennial
Woody shrub with dark green
branches, 3-10 feet tall
Reproduces by seed; seeds are
protected by a flat pod
Soil disturbance results in a new
crop of seedlings
Control:
pull with weed wrenching tool
mow or cut (prior to seed ripening)
apply herbicides to foliage while
actively growing or bark anytime
Reed Canarygrass (Phalaris arundinacea)
Perennial grass
Leaves ¼ - ¾ inches wide
Stems 2-7 feet tall, covered
by waxy coating
Forms thick mat of roots
and rhizomes
Control:
hand pull or mow
solarize
shade out the plant
apply herbicides in early
spring or fall
Purple Loosestrife (Lythrum salicaria)
Perennial
Flowers purple on
spikes
Stems are square; plant
can be 6-8 feet in height
Reproduces by seed
and roots
Control:
cut, dig, or hand pull (small
plants)
cut and remove the flowering
spikes to prevent new seedlings
apply herbicides when actively
growing at full to late flowering
Butterfly Bush (Buddleia davidii)
Perennial
Grows up to 6 feet tall
White, pink, violet or blue
flowers
Brought to the U.S. as an
ornamental; widely planted
Control:
hand pull (seedlings)
apply herbicide to cut stumps
Note: cutting the plant encourages growth
and applying herbicides to leaves is
generally ineffective.
Weed treatment in riparian areas
• Select the most
effective treatment
methods for the site
• If herbicides are used,
be sure the label
allows application
adjacent to or in the
water
• Consider wipe
application or hand
removal
Now what?
• Inventory the plants on
your property
• Identify invasive plants
and weeds
• Do you have a weed
problem? Why?
• What can you
change about the
way you manage
your property to
decrease the weed
population?
ENGLISH IVY
Proper disposal of weeds
• Put fresh noxious and
perennial weed material
in your garbage
• Don’t add it to your
compost bin or yard
debris cart; especially
seeds or root material
• Don’t leave any root
parts or seeds in wet
areas; they will sprout!
Then...
• Determine appropriate
controls and your plans for
the site and start working
• Monitor for invasive plants
• Plant native plants in your
yard after the weeds are
under control
• Marion & Polk SWCDs have
annual native plant sales in
February
• Share this information with
others
Helpful Resources
Pringle Creek Watershed Council…………....503-566-4034
web: www.open.org/pcwc
Marion Soil & Water Conservation District….503-391-9927
web: www.open.org/mariswcd
Oregon Department of Agriculture…………...503-986-4621
web: www.oregon.gov/ODA
OSU Extension - Marion County Office……...503-588-5301
web: extension.oregonstate.edu/marion
Pacific NW Weed Control Handbook
web: weeds.ippc.orst.edu/pnw/weeds
Helpful Books
Weeds of the West
Western US Cooperative Extension Services
Tom Whitson, Editor; 2001
Northwest Weeds
Ronald J. Taylor; 2003
Plants of the Pacific Northwest Coast
Jim Pojar and Andy Mackinnon; 1994
Handbook of Northwestern Plants
Helen Gilkey and LaRea J. Dennis; 2001
Gardening with Native Plants of the Pacific Northwest
Arthur Kruckeberg; 2003
Trees and Shrubs for Pacific Northwest Gardens
John Grant, et. al.; 2003