The fracturing of wells using crude oil and walnut shells was recently introduced in SE. Saskatchewan with remarkable success. This workover treatment showed an ability to penetrate deeply into the low capacity Mississippian carbonates, and to raise production rates by as much as 400% without affecting the acceptable oil/ water ratios. Two case histories are included that indicate some of the conditions under which the treatment can be of value. The monthly oil and water production is tabulated for each of these cases.