Bittercress germinates year-round in the optimal conditions found in nurseries. (Photo by Ron Strahan) Some spurges have a more prostrate growth habit, which can form dense mats. (Photo by Ron Strahan) Woodsorrel are heavy seed producers and possess an efficient method of seed distribution. (Photo by Mark Claesgens)

Bittercress flowers. (Photo by Ron Strahan) Spurge flowers. (Photo by Mark Claesgens) Yellow woodsorrel grows more upright and produces below-ground stems. (Photo by Ron Strahan)