The flowers have petals barely longer than the calyx bracts and many stamens surrounding a single pistil. Mechanical scarification with a scalpel was the only treatment that consistently increased germination 10 . The plant favors nutrient-rich soils and the ability to survive rumen digestion makes barnyards a favored habitat. In prairie crops it is most common on Dark Brown and Black Chernozemic prairie soils. The seed germinates at soil temperatures between 5 and 30 C and is optimum between 15 to 20 C, but within this range, moisture is critical 1 .
Seedlings emerge after rain all summer and into the fall.
Maximum vegetative growth occurs between 18 and 26 C 2 . There are eight Malva sp. Malva neglecta and M. nicaeensis have petals that are twice as long as the calyx bracts whereas in M. parviflora and M pusilla they are barely longer than the calyx. However, the weed's abundance on Alberta cropland doubled between 1980 and 1985. The situation is similar in eastern Canada.