Abstract
This chapter focuses on common ragweed (Ambrosia artemisiifolia), listed as a secondary noxious weed under the Federal Seeds Act, a noxious weed in many provinces in Canada, and primary cause of allergenic hay fever, asthma and eczema. It provides an overview of the fungi (Albugo tragopogi and Phoma sp.) and insects (Zygogramma suturalis and Ophraella communa) that have been used for its management, competitive interactions with other crops, and the evaluation of effectiveness of its biological control agents. Future research prospects are recommended.