Minidoka County, Idaho - Official Website

Home

Departments

Calendar

Photo Gallery

 
Minidoka County, Idaho - Official Website

Home

Departments

Calendar

Photo Gallery

 
[includes/nav/main.htm]

 

Home :: Weed Department :: Noxious Weeds » Poison Hemlock

Poison Hemlock
Apiaceae (= Umbelliferae), the parsnip family

Background

Poison HemlockPoison hemlock is native to Europe. It contains highly poisonous alkaloids toxic to all classes of livestock and humans. It has poisoned many who have mistaken it for parsley. Poison hemlock is often found on poorly drained soils, particularly near streams, ditches, and surface water.

Description

Poison HemlockPoison hemlock is a biennial that grows up to 10 feet tall. Stems are stout, hollow, ridged, and mottled with purple spots. Leaves are shiny green, 3 to 4 times pinnately compound, and clasp the stem at the obvious nodes. Crushed foliage has a disagreeable, mousey odor. Flowers are small, white, and borne in umbrella-shaped clusters about 3 inches across in early summer. Seeds are ridged and flattened, with 2 seeds borne together. The plant has a thick, white taproot.

Distribution

Poison Hemlock distribution mapIt grows throughout the U.S. except from eastern Montana to northeastern Minnesota and south to Nebraska. It has an extensive presence in Idaho.

Control

A biological control agent (a defoliating moth) provides good to excellent but inconsistent control. Herbicides are also available.

 

© 1999 University of Idaho: Text and photographs for these pages from Idaho's Noxious Weeds, by Robert H. Callihan and Timothy W. Miller (revised by Don W. Morishita and Larry W. Lass).

Please contact: Ag Publishing, University of Idaho, Moscow, Idaho 83844-2240; 208 882-7982 visit the Resources for Idaho website at http://info.ag.uidaho.edu, for more information about this or other publications.

 

 

 

-- Home :: Commissioners :: Departments :: Judicial ::Services ::  Links --

-- Commissioners' Proclamation --
-- Terms of Use --
--  Site Map --

©2010 Minidoka County, Idaho
- Web Site by Surf The Snake -
 

 

Home :: Weed Department :: Noxious Weeds » Perennial Pepperweed

Perennial Pepperweed
(broad-leaved peppergrass, tall whitetop, Virginia pepperweed)
Brassicaceae (= Cruciferae), the mustard family

Background

Perennial PepperweedPerennial pepperweed is native to southern Europe and western Asia. It spreads by seed and creeping roots under many different environmental conditions.

Description

Perennial PepperweedPerennial pepperweed grows up to 6 feet tall and has basal leaves that are lance shaped, have long petioles, are up to 12 inches long, and are covered with a waxy layer. Stem leaves are smaller and have shorter petioles, but don't clasp the stem. Leaves have a prominent, whitish midvein. Flowers are white, less than 1/6 inch wide, and develop in dense, rounded clusters at the branch tips from early summer until fall. Fruits are roundish, slightly hairy, measure 1/16 inch in diameter, and contain 2 tiny seeds.

Distribution

Perennial Pepperweed distribution mapPerennial pepperweed is widely scattered throughout the U.S. and in many Idaho counties.

Control

No biological control agents are available for perennial pepperweed, but herbicides are available to provide control.

© 1999 University of Idaho: Text and photographs for these pages from Idaho's Noxious Weeds, by Robert H. Callihan and Timothy W. Miller (revised by Don W. Morishita and Larry W. Lass).

Please contact: Ag Publishing, University of Idaho, Moscow, Idaho 83844-2240; 208 882-7982 visit the Resources for Idaho website at http://info.ag.uidaho.edu, for more information about this or other publications.

 

 

 

-- Home :: Commissioners :: Departments :: Judicial ::Services ::  Links --

-- Commissioners' Proclamation --
-- Terms of Use --
--  Site Map --

©2010 Minidoka County, Idaho
- Web Site by Surf The Snake -