Description of a Weed
There are numerous definitions of a weed, including:
- a plant out of place and not intentionally sown
- a plant growing where it is not wanted
- a plant whose virtues have not yet been discovered. (R.W.Emerson)
- Plants that are competitive, persistent, pernicious, and interfere negatively with human activity (Ross, et. al.)
Cultural weed control – One of the easiest ways to control weeds is through prevention or cultural control. Close planting in the garden can reduce weed growth by eliminating open space. Cover crops are good for this as well. Adding mulch will prevent light from getting to weed seeds and prevents growth. Mechanical weed control –
Mechanical control of common weed plants can be accomplished through hand pulling, hoeing, digging or mowing (which slows growth and reduces seed formation). While these methods are effective, they can be time consuming.
Chemical weed control
Characteristics of weeds
Certain characteristics are associated with and allow the survival of weeds. Weeds possess one or more of the following:
- a) abundant seed production;
b) rapid population establishment;
c) seed dormancy;
d) long-term survival of buried seed;
e) adaptation for spread;
f) presence of vegetative reproductive structures; and
g) ability to occupy sites disturbed by human activities.
Weeds are troublesome in many ways. Primarily, they reduce crop yield by competing for water, light, soil nutrients, and space. Other problems associated with weeds in agriculture include:
- a) reduced crop quality by contaminating the commodity;
b) interference with harvest;
c) serve as hosts for crop diseases or provide shelter for insects to
overwinter;
d) limit the choice of crop rotation sequences and cultural
practices; and
e) production of chemical substances which are toxic to crop plants
(allelopathy), animals, or humans.
Strategies & Activities:
Step: Teacher revises the previous topic.
Step 2: Teacher introduces the new topic.
Step3: Teacher explains the new topic.
Step4: Teacher welcomes pupils’ questions.
Step5: Teacher evaluates the pupils.
Assessment & Evaluation:
- Define weed
- State 3 measures of controlling weeds
- State the characteristics of weed
ASSIGNMENT
- Define weed
- State 3 measures of controlling weeds
- State the characteristics of weed
See also