Pigweed is the name of several species of weeds found in many regions worldwide. The redroot pigweed has large, coarse leaves that may be covered with stiff hairs. Its small greenish flowers grow in densely crowded branchlike heads. This weed measures 4 to 10 feet (1.2 to 3 meters) in height. The smooth pigweed may grow 6 feet (1.8 meters) high. Its leaves and flowers may be green or reddish. Pigweeds can be killed by uprooting the plants completely or by spraying with a herbicide (chemical weedkiller).
