A lawyer representing a Northern California man who claims that exposure to Monsanto Co.’s Roundup weedkiller caused him to develop cancer urged a San Francisco jury to consider the amount and duration of his exposure.

Aimee Wagstaff of Andrus Wagstaff on Tuesday pointed to expert testimony that concluded that her client Edwin Hardeman sprayed about 6,000 gallons of Roundup on his property over a 26-year span. Monsanto’s experts, she argued, didn’t consider the amount her client sprayed or the duration of his exposure when they concluded that Roundup wasn’t a significant factor contributing to his cancer.