Which of the following plants is not classified as forage grass?

This question is asking which plant is not classified as a forage grass. Forage grasses are plants that are specifically grown to provide food for grazing animals such as cattle, sheep, and goats.

Option A: giant star - This is not a commonly known forage grass. It is more likely a type of ornamental plant or a flowering plant.

Option B: guinea grass - This is a type of forage grass that is commonly used for grazing animals. It is known for its high productivity and nutritional value.

Option C: elephant grass - This is another type of forage grass that is widely used for grazing animals. It is known for its fast growth and high yield.

Option D: gamba grass - This is also a type of forage grass that is suitable for grazing animals. It is known for its ability to tolerate drought and its high protein content.

Option E: stylo (Correct) - Stylo is not classified as a forage grass. It is actually a legume plant that is commonly used as a forage crop. Legumes, such as stylo, are known for their ability to fix nitrogen in the soil, which can enhance the growth of other plants.

Therefore, the correct answer is Option E: stylo. It is not classified as a forage grass but rather as a legume plant used for forage purposes.