Hello Karen,

Thank you for your question. 

You didn't clarify how you know the plant is Common buckthorn, (Rhamnus chathartica). Proper identification is an important first step in the process to determine the best treatment plan. Assuming you have correctly identified the plant correctly, can you also clarify if you are referring to a single bush or tree or is it more extensive?

Your response will assist me to provide the best recommendations.

thank you!

I am attaching a spec sheet that will provide information pertaining to correct identification of Common buckthorn. Included with the attachment is a list of helpful links. 

I would recommend you direct your client to the Midwest Invasive Species Information Network (MISIN), as a first step. They may be able to provide you with resources to assist your client with eradication efforts. I cannot recommend private contractors.

MISIN - Midwest Invasive Species Network

You may also refer your client to their local Conservation District office. Home - Michigan Association of Conservation Districts.

They may also be helpful in provide local references to deal with this issue.

I hope your client finds this information useful. 

best regards,