Broad or Narrow Leaves
Broadleaf weeds have two seed leaves (first leaves or cotyledons) as they emerge through the soil (dicotyledonous). Their leaves are generally wider than those of grass weeds (but not always). Veins on the leaves are branched or net-like. Their stems are oval, round or square and are often branched. They may have showy flowers.
Grass weeds have only one seed leaf (cotyledon). Their leaf blades are narrow and have parallel veins (monocotyledonous). Stems are round or oval. They may develop seed heads at the ends of the stems, but if they have flowers they will be inconspicuous.
- Do you know how to tell the difference between grasses, sedges and rushes? Students of botany use the rhyme:
'Sedges have edges,
Rushes are round,
Grasses have nodes from their tips to the ground.'
- This is useful, but not always the case. Grasses have leaves in two rows, their stems are hollow, with nodes wider than the stem. Sedges have stems that are triangular in cross-section and if they have leaves there are three rows. Rushes have cylindrical leaves.
Selective weed killers such as LawnPro Turfclean Ultra, LawnPro Turfclean and LawnPro Prickle and Hydrocotyle will kill broadleaf weeds but not grass, this is why they can be used to kill weeds in lawns.