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Aug 12

Prepping for Fall - Biennial Weed Control

Posted on August 12, 2021 at 10:08 AM by Alicia Doran

Musk thistle habitat.

This time of year we receive a number of inquiries about what to spray on biennial noxious weeds (Common mullein, Musk thistle, Diffuse knapweed)  Well the answer is that this is not the time of year to be spraying these weeds.

Fast Facts

 -  Once biennial weeds form a flower-bud, it is too late to spray

 -  Our biennial weeds reproduce by seed

 -  Our biennial weeds have taproots

Removing this time of year is an option but all flowers need to be bagged and put into the trash/taken to the land fill.  Consider timing your removal activities next year so you target rosettes (fall and spring) and early bolting plants (spring).  That way you will not need to bag and it provides a better opportunity for the native plants to grow

Getting Ready for Fall

This is a good time to assess your management needs so that you are ready for your fall control 

 -  Identify the weeds on your property - knowing which weeds you have is key to deciding your management options

 -  Map your infestations and get an idea of how large an area will need to be managed

 -  Decide on which methods and management tools you will be using.  If you will be using herbicide, decide which ones and purchase

 -  Or, if you will be using a commercial applicator (contractor), get your job on their fall schedule

It can be daunting as you look over your property at large patches of biennial weeds but by refining your efforts and choosing the right timing for your controls, you will see better results and have more time to enjoy the benefits of your labors.