Ageratina altissima (White Snakeroot): white Minnesota wildflowers

Ageratina altissima (White Snakeroot)

Plant Info
Also known as:
Genus:	Ageratina
Family:	Asteraceae (Aster)
Life cycle:	perennial
Origin:	native
Habitat:	shade; thickets, deciduous woods
Bloom season:	summer, fall
Plant height:	1 to 4 feet
USDA PLANTS database:	Minnesota county distribution map
Spotted in Ramsey County at:	Battle Creek Regional Park Long Lake Regional Park Rice Creek Trail Corridor Vadnais/Snail Lake Regional Park

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Detailed Information

Flower:: Flat clusters 1 to 2 inches across made up of tiny 1/6-inch white flowers.
Leaves:: Leaves are 2 to 6 inches long with coarse teeth; wide at the leaf base and pointed at the tip.
Fruit:: Flower heads transform to black seeds with silken parachutes attached to carry them away.
Notes:: When I took a walk through the park in mid-September, the woods there were filled with White Snakeroot. It and Canada Goldenrod were about the only things blooming in the woods.

More photos

full-sized plant, about 4 feet tall

All photos taken at Long Lake Regional Park, New Brighton, MN, July and September 2006.

Comments

Have you seen this plant in Minnesota, or have any other comments about it?

Posted by: Carrie Anne in Minneapolis, MN
on: 2010-08-19 14:45:30

Having just positively identified this as growing in my yard, I also went to do a little more research on it. I learned something very important! It contains tremetol, a toxin that has killed humans (notably Abraham Lincoln's mother), when passed on from cow's milk. There are more details on "milk sickness" here at: http://en.wikipedia.org/wiki/Milk_sickness. I think this is very important to note as I have a 3 yr old, but I also want to maintain native plants in my yard, and now I will know to keep an eye on him around this plant.

Posted by: Mary Beth in Twin Cities
on: 2010-08-28 11:52:11

Many non-native garden and house plants are also toxic when ingested - lilies of the valley, azaleas, hydrangeas. However, white snakeroot has been used to treat snakebite. I taught my son not to touch any plant until he learned which ones were safe.