Chapter 18.340 NATIVE PLANT LIST

Chapter 18.340
NATIVE PLANT LIST

Sections:

18.340.030 Modification to the lists and case-by-case exemptions.

18.340.040 Native plants, nuisance plants and prohibited plants.

18.340.010 Purpose.

The purpose of this chapter is to establish a list of allowed, preferred and prohibited plant species for situations where the city requires plantings, such as mitigation plantings for impacts to critical areas and buffers in Chapter 18.300 LCMC. [Ord. 2009-01 § 1, 2009.]

18.340.020 Applicability.

(1) Any mitigation planting required pursuant to Chapter 18.300 LCMC shall use plants on the native plant list and not plants on the nuisance or prohibited plant lists. All property owners throughout the city shall avoid use of plants from the nuisance plant list and shall not landscape with any plants on the prohibited plant list.

(2) In situations where city review and approval of a landscaping plan is not required, the city strongly discourages use of plants on the nuisance and prohibited plant lists; however, unless specifically prohibited elsewhere in this code, this chapter does not prohibit use of these plants. [Ord. 2009-01 § 1, 2009.]

18.340.030 Modification to the lists and case-by-case exemptions.

The planning director may recommend the addition or removal of species from any of the three plant lists in this chapter in response to a request concerning a particular species or when a state or federal agency designates a particular species as invasive, a pest or prohibited. In all instances, the planning director will consult with appropriate professionals having botanical or ecological expertise to determine whether the plant in question should be added or deleted. The planning director is authorized to grant case-by-case exemptions to the prohibitions of this chapter in response to a specific request for a particular species, which includes documentation and an explanation as to why the species is not, and will not become, a nuisance. [Ord. 2009-01 § 1, 2009.]

18.340.040 Native plants, nuisance plants and prohibited plants.

(1) The native plant list in this section identifies native plants historically found in southwest Washington and is divided into three groups: trees, shrubs, and herbaceous ground covers. Shrubs may not be used to meet criteria or conditions of approval that require trees. Indicator status refers to the frequency with which a plant occurs in a wetland, as derived from the National List of Plant Species That Occur in Wetlands: 1988 National Summary (USFWS, Biological Report 88(24), 1988). The indicator categories are as follows:

(a) Obligate wetland (OBL) plants occur almost always (estimated probability greater than 99 percent) under natural conditions in wetlands.

(b) Facultative wetland (FACW) plants usually occur in wetlands (estimated probability 67 percent to 99 percent), but occasionally found in nonwetlands.

(c) Facultative (FAC) plants are equally likely to occur in wetlands or nonwetlands (estimated probability 34 percent to 66 percent).

(d) Facultative upland (FACU) plants usually occur in nonwetlands (estimated probability 67 percent to 99 percent), but are occasionally found in wetlands (estimated probability one percent to 39 percent).

(e) Obligate upland (UPL) plants occur in wetlands in another region, but occur almost always (estimated probability greater than 99 percent ) under natural conditions in nonwetlands in the Northwest region.

A positive (+) sign used with an indicator category means that the plant occurs more frequently at the higher end of the range. For example, FACW+ indicates that the plant is typically found in local wetlands with an estimated probability of 83 percent to 99 percent. A negative (-) sign indicates a frequency toward the lower end of the range (less frequently found in wetlands). An NI (no indicator) is shown for those species for which there is insufficient information to determine an indicator status. If no category or symbol is shown for a plant, it does not occur in wetlands.

(2) Native Plants. Native plants can be acquired through many local and specialty plant nurseries. For particularly large orders or less common plant species, growers will need time to propagate and raise plants before they are ready for installation. For this reason, growers may need advance notice of plant orders and project timelines should allow adequate time to fill such orders.

Table 18.340.040(2) Native Plant List
Scientific Name	Common Name	Indicator
TREES
Abies grandis	Grand Fir	FACU-
Acer macrophyllum	Big-Leaf Maple	FACU
Alnus rubra	Red Alder	FAC
Arbutus menziesii	Pacific Madrone	NI
Cornus nuttallii	Pacific Dogwood	NI
Fraxinus latifolia	Oregon Ash	FACW
Pinus contorta var. contorta	Shore Pine	FAC
Pinus monticola	White Pine	FACU
Populus balsamifera L. ssp. trichocarpa	Black Cottonwood	FAC
Populus tremuloides	Quaking Aspen	FAC+
Prunus emarginata	Bitter Cherry	FACU
Prunus virginiana	Choke Cherry	FACU
Picea sitchensis	Sitka Spruce	FAC
Pseudostuga menziesii	Douglas Fir	FACU
Rhamnus purshiana	Cascara	FAC-
Quercus garryana	Oregon White Oak	NI
Salix lucida ssp. lasiandra	Pacific Willow	FACW+
Salix scouleriana	Scouler’s Willow	FAC
Thuja plicata	Western Red Cedar	FAC
Tsuga heterophylla	Western Hemlock	FACU-
SHRUBS
Acer circinatum	Vine Maple	FAC-
Amelanchier alnifolia	Serviceberry	FACU
Arctostaphylos columbiana	Hairy Manzanita	NI
Arctostaphylos uva-ursi	Kinnikinnick	FACU-
Ceanothus velutinus	Snowbrush	NI
Cornus canadensis	Bunchberry	FAC
Cornus stolonifera	Red-Osier Dogwood	FACW
Corylus cornuta var. californica	Beaked Hazelnut	FACU
Crataegus douglasii	Black Hawthorn	FAC
Gaultheria shallon	Salal	FACU
Holodiscus discolor	Oceanspray	NI
Lonicera involucrata	Black Twinberry	FAC+
Lonicera ciliosa	Honeysuckle	NI
Mahonia aquifolium	Tall Oregon Grape	NI
Mahonia nervosa	Dull Oregon Grape	NI
Malus fusca	Pacific Crabapple	FACW
Oemleria cerasiformis	Osoberry	FACU
Philadelphis lewisii	Mock Orange	NI
Physocarpus capitatus	Pacific Ninebark	FACW-
Ribes lacustre	Swamp Black Currant	FAC+
Ribes sanguineum	Red Flowering Currant	NI
Rosa gymnocarpa	Baldhip Rose	FACU
Rosa nootkana	Nootka Rose	FAC
Rosa pisocarpa	Clustered Wild Rose	FAC
Rubus parviflorus	Thimbleberry	FAC-
Rubus spectabilis	Salmonberry	FAC+
Salix sitchensis	Sitka Willow	FACW
Sambucus caerulea	Blue Elderberry	FACU
Sambucus racemosa	Red Elderberry	FACU
Spiraea douglasii	Hardhack	FACW
Symphoricarpos albus	Snowberry	FACU
Vaccinium ovatum	Evergreen Huckleberry	NI
Vaccinium parviflorum	Red Huckleberry	NI
Viburnum edule	High Bush Cranberry	FACW
HERBACEOUS PLANTS
Achillea millefolium	Yarrow	FACU
Achlys triphylla	Vanilla Leaf	NI
Adiantum pedatum	Maidenhair Fern	FAC
Agropyron trachycaulum	Slender Wheatgrass	FAC
Agrostis exerata	Spike Bentgrass	FACW
Agrostis idahoensis	Idaho Bentgrass	FAC+
Alopecurus geniculatus	Water Foxtail	OBL
Alisma plantago-aquatica	Water Plantain	OBL
Allium cernuum	Nodding Onion	NI
Anaphalis margaritacea	Pearly Everlasting	NI
Aquilegia formosa	Red Columbine	FAC
Aruncus dioicus	Goats Beard	FACU+
Aster subspicatus	Douglas Aster	FACW
Asarum caudatum	Wild Ginger	FACU
Athyrium filix-femina	Lady Fern	FAC
Beckmania syzigachne	American Sloughgrass	OBL
Blechnum spicant	Deer Fern	FAC+
Boykinia elata	Coast Boykinia	NI
Boykinea major	Meadow Boykinia	NI
Bromus vulgaris	Columbia Brome	UPL
Camassia leichtlinii	Great Camas	FACW-
Camassia quamish	Common Camas	FACW
Carex aperta	Columbia Sedge	FACW
Carex arcta	Clustered Sedge	OBL
Carex bebbi	Bebb’s Sedge	OBL
Carex cusickii	Cusick’s Sedge	OBL
Carex deweyana	Dewey Sedge	FACU
Carex grayi	Gray’s Sedge	NI
Carex lenticularis	Lens Sedge	FACW+
Carex leporina	Hare Sedge	FACW
Carex lyngbyei	Lyngby’s Sedge	OBL
Carex obnupta	Slough Sedge	OBL
Carex pachystachya	Thick Headed Sedge	OBL
Carex scoparia	Blunt Broom Sedge	FACW
Carex stipata	Awl Sedge	NI
Carex tumulicola	Foothills Sedge	FACU
Carex unilateralis	One-Sided Sedge	FACW
Carex vesicaria	Blister Sedge	OBL
Carex vulpinoidea	Fox Sedge	OBL
Clarkia amoena	Purple Clarkia	NI
Corydalis scouleri	Scouler’s Corydalis	FAC+
Danthonia californica	California Oatgrass	FACU
Deschampsia caespitosa	Tufted Hairgrass	FACW
Deschampsia danthonoides	Annual Hairgrass	FACW-
Deschampsia elongate	Slender Hairgrass	FACW-
Dicentra formosa	Pacific Bleeding Heart	FACU
Disporum hookeri	Hooker’s Fairybell	NI
Dodecatheon pulchellum	Shooting Star	FACW
Dryopteris expansa	Wood Fern	NI
Eleocharis acicularis	Needle Spike Rush	OBL
Eleocharis ovata	Ovoid Spike Rush	OBL
Eleocharis palustris	Creeping Spike Rush	OBL
Elymus glaucus	Blue Wildrye	FACU
Epilobium angustifolium	Fireweed	FACU+
Festuca megalura	Foxtail Fescue	NI
Festuca ovina	Blue Fescue	FACU
Festuca rubra	Red Fescue	FAC+
Festuca subiliflora	Coast Fescue	NI
Frageria virginiana	Wild Strawberry	FACU
Glyceria elata	Tall Mannagrass	FACW+
Glyceria grandis	American Mannagrass	NI
Glyceria occidentalis	Western Mannagrass	OBL
Glyceria striata	Fowl Mannagrass	OBL
Hordeum brachyantherum	Meadow Barley	FACW-
Hordeum depressum	Alkali Barley	FACW
Hordeum jubatum	Foxtail Barley	FAC
Iris tenax	Oregon Iris	NI
Juncus acuminatus	Tapered Rush	OBL
Juncus balticus	Baltic Rush	FACW+
Juncus bufonius	Toad Rush	FACW
Juncus ensifolius	Dagger Leaf Rush	FACW
Juncus tenuis	Slender Rush	FACW-
Koeleria cristata	Prairie Junegrass	NI
Leersia oryzoides	Rice Cutgrass	OBL
Linnea borealis	Twinflower	FACU-
Luzula parviflora	Small-Flowered Wood Rush	FAC-
Melica smithii	Oniongrass	NI
Mimulus guttatus	Yellow Monkey Flower	OBL
Oxalis oregana	Wood Sorel	NI
Poa compressa	Canada Bluegrass	FACU+
Polypodium glychorhiza	Licorice Fern	NI
Polystichum munitum	Sword Fern	FACU
Sagittaria latifolia	Wapato	OBL
Scirpus americanus	Three Square Bullrush	OBL
Scirpus cyperinus	Wool Bullrush	OBL
Scirpus fluviatilis	River Bullrush	OBL
Scirpus lacustris	Soft Stem/Hard Stem Bullrush	OBL
Scirpus maritimus	Seacoast Bullrush	OBL
Scirpus microcarpus	Small Fruited Bullrush	OBL
Sedum oreganum	Stonecrop	NI
Tolmia menziesii	Youth on Age	FAC

(3) Nuisance Plants. Plants are included on the nuisance plant list for two primary reasons:

(a) Plants considered a nuisance because of their tendency to dominate plant communities or plants considered to be harmful to public facilities such as sewer lines, sidewalks, roads and the like; and

(b) Plants considered harmful to humans and other animals.

Additionally, nuisance plants are also those listed by a state or federal agency as noxious or prohibited, such as Washington’s noxious weed list. As such, their introduction or continuation may be inappropriate. Plants on this list can be removed and are prohibited in all city reviewed landscape plans. Nuisance plants may be native, naturalized or exotic and are divided into two groups: plants that are considered a nuisance because of their tendency to dominate plant communities, and those considered harmful to humans and other animals.

Table 18.340.040(3) Nuisance Plant List
Scientific Name	Common Name	Type
Acer platanoides	Norway Maple	Dominating
Acer pseudoplatanus L.2	Sycamore Maple	Dominating
Ailanthus altissima	Tree-of-Heaven	Dominating
Alliaria officinalis, A. petiolata	Garlic Mustard	Dominating
Betula sp.	Birch	Dominating
Buddleia davidii	Butterfly Bush	Dominating
Chelidonium majus	Lesser Celandine	Dominating
Cirsium arvense	Canada Thistle	Dominating
Cirsium vulgare	Common Thistle, Bull Thistle	Dominating
Clematis ligusticifolia	Western Clematis	Dominating
Clematis vitalba	Traveler’s Joy	Dominating
Conium maculatum	Poison-Hemlock	Harmful
Convolvulus arvensis	Field Morning-Glory, Field Bindweed	Dominating
Convolvulus seppium	Lady’s-Nightcap	Dominating
Cortaderia selloana	Pampas Grass	Dominating
Crataegus sp. except C. douglasii	Hawthorn, Except Native Species	Dominating
Cytisus scoparius	Scotch Broom	Dominating
Daucus carota	Queen Anne’s Lace	Dominating
Elodea densea	South American Waterweed	Dominating
Equisetum arvense	Common Horsetail	Dominating
Equisetum telemateia	Giant Horsetail	Dominating
Erodium cicutarium	Crane’s Bill	Dominating
Geranium robertianum	Robert Geranium, Herb Robert	Dominating
Hypercium perforatum	St. John’s Wort	Dominating
Ilex aquafolium	English Holly	Dominating
Laburnum watereri	Goldenchain Tree	Harmful
Lemna minor	Duckweed, Water Lentil	Dominating
Leontodon autumnalis	Fall Dandelion	Dominating
Lythrum salicaria	Purple Loosestrife	Dominating
Myriophyllum spicatum	Eurasian Watermilfoil	Dominating
Pharais arundinacea	Reed Canarygrass	Dominating
Poa annua	Annual Bluegrass	Dominating
Polygonum coccineum	Water Smartweed	Dominating
Polygonum convolvulus	Climbing Bindweed	Dominating
Polygonum sachalinense	Giant Knotweed, Bohemian Knotweed	Dominating
Prunus laurocerasus	English, Portugese Laurel	Dominating
Ranunculus repons	Creeping Buttercup	Dominating
Rhus diversiloba	Poison Oak	Harmful
Rubus laciniatus	Evergreen Blackberry	Dominating
Rubus ursinus	Pacific Blackberry	Dominating
Senecio jacobaea	Tansy Ragwort	Dominating
Solanum dulcamara	Blue Bindweed	Dominating
Solanum nigrum	Garden Nightshade	Harmful
Solanum sarrachoides	Hairy Nightshade	Dominating
Taraxacum officinale	Common Dandelion	Dominating
Taxus brevifolia	Pacific Yew	Harmful
Utricularia vulgaris	Common Bladderwort	Dominating
Various genera	Bamboo sp.	Dominating
Vinca major	Periwinkle (Large Leaf)	Dominating
Xanthium spinosum	Spiny Cocklebur	Dominating

(4) Prohibited Plants. Plants listed as prohibited are prohibited in all reviewed landscaping situations in the city because their growth damages sewer lines, sidewalks and other public facilities, they pose a serious threat to the health and vitality of native plant and animal communities and/or have been designated by state or federal agencies as prohibited. This prohibition applies only to the species listed below, including any subspecies, varieties or cultivars of these species. Pre-existing in-ground plantings are exempt from this provision. Additional plant species may be prohibited by other regulations in specific areas or situations.

Table 18.340.040(4) Prohibited Plant List
Scientific Name	Common Name
Acer macrophyllum1	Oregon or Big-Leaf Maple
Acer pseudoplatanus L.2	Sycamore Maple
Ailanthus altissima, A. glandulosa1, 3	Tree-of-Heaven
Alnus rubra2	Red Alder
Betula pendula2	White Birch
Crataegus laevigata, C. oxycarpa2	Hawthorn-Paul’s Scarlet
Cytisus scoparius	Scotch Broom
Hedera helix	English Ivy
Iris pseudacorus	Yellow Flag Iris
Lythrum salicaria	Purple Loosestrife
Phalaris arundinacea4	Reed Canarygrass
Platanus acerifolia1, 3	London Plane
Populus alba, P. canandensis1, 3	Poplar
Populus balsamifera L. ssp. trichocarpa1	Black Cottonwood
Populus trichocarpa1	Cottonwood
Rubus discolor	Himalayan Blackberry
Salix sp.1, 3	Willow
Salix lucida ssp. Lasiandra4	Pacific Willow
Sorbus sp.1	Mountain Ash
Ulmus americana2	American Elm
Ulmus hollandica2	Dutch Elm
Ulmus pumila2	Siberian Elm

1 Prohibited within 100 feet of sewer mains

2 Prohibited within 10 feet of public rights-of-way, sidewalks or parking lots

3 Prohibited within five feet of sidewalks

4 Prohibited outside of wetlands

[Ord. 2009-01 § 1, 2009.]