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Earthshare of Washington

Home > Invasive Species

Collections Needed

Need help with identification?  Try:

Google Image Search

Plants of Washington Image Collection

Cowlitz County (32 taxa)

Scientific Name
Noxious Weed Class
Phenology*
Collector**

Artemisia absinthium

C
7-10
 
Centaurea solstitialis
B
7-10
 

Centaurea stoebe

B
7-10
Barbara Wilson w/Nick Otting

Centaurea × moncktonii

B
8-9
W.J. Eyerdam
Centaurea diffusa
B
7-10
 

Centaurea nigra

B
5-10
 

Cirsium arvense

C
7-9
 
Cirsium vulgare
C
7-10
 

Clematis vitalba

C
7-10
 
Conium maculatum
C
4-10
 

Convolvulus arvensis

C
5-10
 
Daphne laureola
Monitor
1-5
 
Egeria densa
B
5-10
 

Geranium robertianum

B
4-8
R.D. Chitwood

Hedera helix

C
9-5
Peter F. Zika

Hypericum perforatum

C
6-10
 
Kochia scoparia
B
9-12
 
Lepidium latifolium
B
5-9
 

Linaria dalmatica

B
5-9
 

Lythrum salicaria

B
7-9
Ben Legler w/Peter F. Zika, David Giblin

Myriophyllum spicatum 

B
8-10
P.F. Zika w/ F. Weinmann

Phalaris arundinacea

C
5-10
 
Polygonum polystachyum
B
8-10
 

Polygonum cuspidatum 

B
8-9
 

Potentilla recta

B
6-8
 

Proboscidea louisianica

Monitor
8-10
 

Rorippa nasturtium-aquaticum

Monitor
4-9
 

Senecio jacobaea

B
7-10
 

Silybum marianum

A
6-10
Peter F. Zika
Solanum rostratum
A
8-9
 

Tanacetum vulgare

C
7-9
 

Verbascum thapsus

Monitor
5-10
 

* The numbers represent months of the year when the species has been collected, extracted from herbarium labels at WTU (with a few dates based on records at MO, NY, UC, and UBC).

On-line data sources for phenology:

MO:    http://mobot.mobot.org/W3T/Search/vast.html

NY:     http://sciweb.nybg.org/science2/vii2.asp

UBC:   http://herbarium.botany.ubc.ca/herbarium_data/vascular/search.htm

UC:     http://www.mip.berkeley.edu/www_apps/smasch/

WTU:   http://biology.burke.washington.edu/herbarium/collections/vascular/basicsearch.php

** email wnps@wnps.org when you've made a collection and we will put your name onto the list, this will help us minimalize duplication of efforts.  Use the email subject line:  Herbarium Collection