Butterweed (Packera glabella)

About Butterweed:

Butterweed is a winter annual weed that prefers cool seasons and germinates in the fall. If consumed in large amounts, it becomes fatal to the liver of livestock. Death will occur 1 to 2 days after cattle have consumed 4 to 8% of their body weight in butterweed. It has also been shown to cause abortions in cattle, making it essential that Butterweed is removed from pastures.

Family: Asteraceae family

Butterweed Scouting and Prevention:

Butterweed typically grows 18 to 20 inches tall and in ideal situations, they can grow up to 40 inches. The stem of a Butterweed is hollow with a pink to purple at the base, transitioning to green halfway up the stem. They have no branches except for small ones that grow out of the top leaves. On these branches lie numerous amounts of yellow flowers that bloom from March to May. The leaves on a Butterweed are rounded lobes with about 5 pairs getting bigger as they reach the end of each branch.

Common locations

• - Damp/ Wet land
• - Heavy loam soil
• - Heavy clay soil
• - Meadows

Prevention

Prevention of Butterweed is less expensive and less time-consuming then trying to control it. Make sure when you seed a new area you do so with certified weed-free seeds. If there is an infested area on your property, be sure to drive around instead of through it. Finally, make sure to give all equipment that has been in infested fields a good clean to make sure no seeds are transferred. If you have had Butterweed in your field in past years, it is very important that you scout your fields during the winter months to make sure you deal with this weed as soon as it emerges.

Butterweed Control:

Cultural Control

One of the best ways to culturally control Butterweed is to have a good crop rotation, which is beneficial in minimizing butterweed. Also, having a winter cover crop in your rotation of wheat or oats will hold down the germination of Butterweed seed.

Chemical Control

Successful chemical control over Butterweed has been done with 2,4-D herbicide when it is still a young weed. Due to the fact that 2.4-D has limited residual activity, you may need to apply more than one round of application. GrazonNext and Milstone herbicides have been shown to work well on Butterweed through any growth stage.

Latin / Alternative Butterweed names:

• - Yellowtop Butterweed
• - Grassleaf Groundsel
• - Cresslead Groundsel

Additional Butterweed Resources