Weed Classification

Weeds are classified according to their similarities and differences which are effective in formulating an effective control program. These are according to their: a) Life Cycle, b) Gross Morphological Features, c) Body Texture, d) Habit-Manner of Growth, and e) Habitat.

According to their Life Cycle, weeds are classified as annual, or perennial. Annual weeds complete their life cycle in one season and reproduce mainly by seeds while perennial weeds live for more that one season and reproduce vegetatively and by seeds. They can either be simple perennials that reproduce only by seeds or creeping perennials that reproduce by seeds and by vegetative propagules.

Weeds are classified according to their Morphological Features can be grass, sedge, or broadleaf. Grasses have stems called culms that are cylindrical and has has a well defined nodes and internodes. Their leaves arise alternately in two rows. Ligules can be observed in grasses. Sedges on the other hand have triangular culms and does not have ligules. Their nodes and internodes are indistinct which are located at the basal part of the culm. Broadleaved weeds are characterized as having expanded leaves. They can either be monocots or dicots.

We classify weeds as herbaceous, woody, or vine according to the general appearance of their stems. Their habit of growth can be erect-those that have an upwight growth, prostrate-lying flat on the ground, or twining-those that are climbing or clinging for support.

Weeds can be aquatic-those living in water, terrestrial-grows on land, or aerial-or epiphytes growing in air or attached to trees or other support, according to their habitat.