Home
About Us
Weeds
Weed Alerts
Declared Noxious Weeds
Herbs
Artichoke thistle
Bathurst/Noogoora burr
Black Knapweed
Blue Hound's Tongue
Branched broomrape
Buffalo Burr
Burr ragweed
Chinese violet
Crofton Weed
Devils Claw Purple flowered
Devils Claw Yellow flowered
Fireweed
Golden thistle
Hawkweeds
Hemlock
Horehound
Long-leaf willow primrose
Mexican poppy
Mistflower
Nodding Thistle
Parthenium Weed
Paterson's Curse or Salvation Jane
Perennial Canada Thistle
Perennial Ragweed
Scotch, Illyrian & Stemless Thistle
Silver Leaf Nightshade
Soldier thistle
Spotted Knapweed
St Johns Wort
Star Thistle
Vipers Bugloss or blue weed
Wild Radish
Witchweed
Trees
Grasses
Shrubs
Vines
Aquatic
Noxious Weeds Act
Plans and Strategies
News
Links
Weed Resources
Contact
 

Hemlock

Hemlock2

Hemlock3

Hemlock1

Hemlock plants

Hemlock flower close-up

Fennel1

Fennel2

Fennel3

Daucus carota1

Daucus carota2

Daucus carota3

Daucus carota4

Trachy aniso1

Trachy aniso2

Trachy aniso3

Trachy aniso4



BOTANICAL NAME

Conium maculatum


Family

Apiaceae (formerly Umbelliferae, carrot, parsley etc)

Status

Hemlock is declared noxious in the Southern Tablelands and South East Region in Bombala, Eurobodalla, Palerang, Queanbeyan, Upper Lachlan and Wingecarribee LCAs in class 4.

Description

Robust annual or biennial herb 1 to 2m high with zigzagging stems, which have a whitish bloom, are finely blotched brown or purple, and are hollow. The leaves are finely divided and ferny in appearance. Flowers are small, white, and carried in branching umbrella-shaped heads. Hemlock is said to have a "mousy" smell when crushed.

preferred habitat and impacts


Usually found on waste ground in moist conditions, such as river banks and around the edges of pasture. Hemlock can form large stands in suitable conditions. It is a significant weed because all parts of the hemlock plant are poisonous to humans and livestock if eaten. It causes death by respiratory paralysis. Handling the plant may cause dermatitis in some people. It also taints milk and can affect yield, and if consumed in sub-lethal doses, may cause birth deformities. It is rarely eaten green by stock, but may be consumed when incorporated into hay or silage.

Dispersal


Seed is spread by water, machinery or vehicles, or in contaminated soil or by wind over short distances.

look-alikes


Another weed in the same family, wild carrot (Daucus carota) can be locally common on roadsides (for example on the south coast). It has similar heads of white or pinkish flowers, and the crushed leaves smell carroty. Fennel (Foeniculum vulgare) has a similar habit but narrower leaf segments and yellow flowers. Control both these weeds as for hemlock.
A tall annual or biennial native herb Trachymene composita (formerly anisocarpa) has similar branched umbrella-like heads of white flowers to those of wild carrot and hemlock. Its leaves are less divided, being composed of three lobed leaflets. It grows in two very different habitats, in wet sandy soils close to swamps on the coast and in subalpine woodland or montane forest after fires, when it may become very abundant.

control


Hand chip small hemlock infestations or spot spray actively growing young plants before they elongate into the flowering stage, preferably with a selective woody weed herbicide. Slashing just before flowering may kill the plants, or some new growth may occur and need follow-up treatment.