Physocarpus malvaceus is a species of flowering plant in the rose family known by the common name mallow ninebark. It is native to western North America, where its distribution extends from British Columbia to Nevada to Wyoming. This shrub is a pioneer species that increases after disturbance and decreases as the overstory grows back and shades it out. It grows rapidly after events such as wildfire, sprouting up from its rhizomes. It is considered a "fire-resistant" plant. It survives fire and resprouts, becoming more common on burned sites than unburned.