Grass is the common name for plants in the Poaceae family. There are over 11,000 grass species, but ornamental grasses and turf grasses account for the vast majority of cultivated grass varieties. Cereal grasses, bamboos, and grasses of natural grassland, as well as species cultivated in lawns and pasture, are all included in grasses. In this article, we will discuss Grasses which will be helpful for UPSC exam preparation.

Growth and Development of Grasses

• Grass blades develop from the base of the blade rather than from elongated stem tips.
• This low growth point evolved in response to grazing animals and allows grasses to be grazed or mowed on a regular basis without causing severe plant damage.
• There are three types of grass growth habits: bunch-type (also known as caespitose), stoloniferous, and rhizomatous.
• The success of grasses is due to their morphology and growth processes, as well as their physiological diversity.
• C3 and C4 grasses are classified according to their photosynthetic pathway for carbon fixation.
• C4 grasses have a photosynthetic pathway that is linked to specialised Kranz leaf anatomy, allowing for increased water use efficiency and making them more adapted to hot, arid environments.

Grasses - Ecology

• Grasses dominate many habitats, including grassland, salt marsh, reedswamp, and steppes.
• They are also found as a minor component of the vegetation in almost every other terrestrial habitat.
• Grass-dominated biomes are called grasslands. If only large, contiguous grasslands are counted, these biomes cover 31% of the planet's land surface.
• Pampas, steppes, and prairies are examples of grasslands.
• Many grazing mammals, as well as many species of butterflies and moths, feed on grasses.
• Many animals, known as graminivores, eat grass as their primary source of food, including cattle, sheep, horses, rabbits, and many invertebrates such as grasshoppers and the caterpillars of many brown butterflies.
• Grasses are also consumed by omnivorous and, on rare occasions, carnivorous animals.
• Grasses dominate certain biomes, particularly temperate grasslands, due to the adaptation of many species to grazing and fire.

Grass Varieties Found in India

Doab Grass (Cynodon dactylon)

• Indian doab is a green colour grass also known as Durva and Doab, which is important in Lord Ganesha worship.
• The sacred grass is also used in Ancient India's Ayurvedic system and for traditional medicine.

Lemon Grass (Cymbopogon citratus)

• This plant is native to Southeast Asia and has been used in Indian traditional medicine for its leaves, stem, and sprout roots.
• Lemongrass is most commonly grown for medicinal and culinary purposes. It is also used to make sprays, soaps, oil, tea, and as a flavouring agent in culinary.

Kans Grass (Saccharum spontaneum)

• Kans Grass is native to the Indian Subcontinent and an important habitat for the Indian rhinoceros in Assam.
• The wild sugarcane grass along with baruwa grass has native distribution area in mostly northeastern Indian states, particularly in Assam within the Terai-Duar grasslands.

Ravenna Grass (Saccharum ravennae)

• In India, ravenna grass is known as elephant grass and ikora in Assamese.
• Elephant grass is a large, tall grass that grows in moist and wet habitats in India.
• The tallest elephant grass can be found in the Terai-Duar savanna and grasslands of Assam.

Sewan Grass (Lasiurus scindicus)

• Sewan grass is a productive grass found primarily in the arid region of Rajasthan in the Indian Thar desert.
• This is a native grass of India and is known as the "King of Desert Grasses."
• It can be found in the dry areas of Jaisalmer, Barmer, and Bikaner.

Carpet Grass (Stenotaphrum secundatum)

• Stenotaphrum secundatum is a well-known species of grass that forms a thick to medium surface and is popular as lawn grass.
• The dark green grass with a broad and flat blade that is commonly found in lagoons and marshes.

Manila Grass (Zoysia matrella)

• Manila grass, also known as Korean grass, is a popular ornamental grass that is also used as a turf grass in India and the United States.
• Zoysia matrella is indigenous to Asia's temperate coasts and can also be found on the islands of the eastern Indian Ocean.

Napier Grass (Pennisetum purpureum)

• The Napier grass species is native to the African grasslands but is now cultivated in other parts of the world.
• It is particularly suitable for feeding cattle and buffaloes.
• Napier grass, also known as elephant grass, is a popular fodder crop among dairy farmers in India.

Desho grass (Pennisetum pedicellatum)

• Desho grass is known as Deenanath grass in India and it grows naturally in India and where it is native.
• Perennial herb harvested and stored as cattle feed in the highlands of Ethiopia

Foxtail Bristle Grass (Setaria faberi)

• The giant foxtail bristle-grass species of grass is also known as wild foxtail and green foxtail.
• Setaria viridis and Setaria faberi are two distinct species, and wild plants in India emerge from seeds during the monsoon season.

Big Leaf Grass (Setaria megaphylla)

• Another common species of big leaf grass found near water bodies such as rivers or forests is Setaria megaphylla.
• The giant bristle grass is found in India on occasion, usually after the monsoon, and grows in various parts of the country.

Congress Grass (Parthenium hysterophorus)

• Gajar Ghans is a poisonous plant that causes allergies in humans and livestock.

Grasses - Uses

Production of Food

• 70% of all crops grown are grasses.
• Cereals or grains are agricultural grasses grown for their edible seeds.
• Rice, wheat, and maize (corn) account for more than half of all calories consumed by humans.
• Cereals are the primary source of carbohydrates and possibly the primary source of protein for humans; these include rice (in southern and eastern Asia), maize (in Central and South America), and wheat and barley (in Europe, northern Asia and the Americas).
• The main source of sugar production is sugarcane.
• Sugarcane is also used to make sprouted grain, shoots, and rhizomes, as well as sugarcane juice and plant milk, as well as rum, beer, whisky, and vodka.
• Bamboo shoots are used in a variety of Asian dishes and broths, and can be found in supermarkets in sliced, fresh, fermented, and canned forms.
• Lemongrass is a grass that is used in cooking because of its citrus-like flavour and scent.
• Many species of grass are grown as pasture for foraging or as fodder for prescribed livestock feeds, particularly in the case of cattle, horses, and sheep.

Industry

• Grasses are used as a raw material for a variety of applications, including construction and the composition of building materials such as cob, insulation, and the production of paper and board.
• Grass fibre can be used to make paper, biofuel, nonwoven fabrics, and as a substitute for glass fibres in reinforced plastics.
• Bamboo scaffolding can withstand typhoon-force winds, which would destroy steel scaffolding.
• Larger bamboos and Arundo donax have strong culms that can be used similarly to timber.
• Arundo is used to make reeds for woodwind instruments, and bamboo is used for a variety of implements.

Lawn and Ornamental Applications

• Grasses are the most common plant used in lawns, which evolved from grazed grasslands in Europe.
• They are also an important source of erosion control (e.g., along roadsides), particularly on sloping land.
• Many sports, including football (soccer), American football, tennis, golf, cricket, softball, and baseball, use grass lawns to cover their playing surfaces.
• For their foliage, inflorescences, and seed heads, ornamental grasses such as perennial bunch grasses are used in many styles of garden design.
• They are frequently used in natural landscaping, xeriscaping, slope and beach stabilisation, wildlife gardening, and native plant gardening.
• They are used as hedges and screens.

Conclusion

Grasses are possibly the most economically important plant family in human terms. Their economic significance stems from a variety of sources, including food production, industry, and lawns. For up to 6,000 years, they have been grown as food for domesticated animals, and grass grains such as wheat, rice, maize (corn), and barley have been the most important human food crops. Grasses are also used to make thatch, paper, fuel, clothing, insulation, fence posts, furniture, scaffolding and construction materials, floor matting, sports turf, and baskets.

FAQs

MCQs

1. Which of the following is a primary use of cereal grasses in agriculture?

A) Ornamental purposes
B) Food production
C) Biofuel production
D) Livestock feed

2. What is a major benefit of grasses in soil management?

A) Reduces carbon footprint
B) Enhances soil structure and prevents erosion
C) Increases water demand
D) Compacts soil to prevent waterlogging

3. Which grass is commonly used in livestock feed?

A) Rice
B) Ryegrass
C) Bamboo
D) Cattail

4. What factor influences the growth of grasses in agriculture?

A) Only temperature
B) Soil type and temperature
C) Only precipitation
D) Soil fertility and temperature

5. What is a challenge in growing grasses for agriculture?

A) High nutrient requirements
B) Limited commercial value
C) Resistance to pests
D) Inability to adapt to varying climates

GS Mains Questions and Model Answers

Q1: Discuss the role of grasses in sustainable agricultural practices.

Answer: Grasses play a critical role in sustainable agriculture by providing a natural solution for soil health, erosion control, and biodiversity. Forage grasses are essential in grazing systems that sustain livestock farming. Grasses like switchgrass and miscanthus are also being researched for their potential in biofuel production, offering a renewable energy source. In addition, grasses contribute to soil fertility by fixing nitrogen and adding organic matter to the soil. By supporting crop rotation systems, grasses help maintain ecological balance and reduce the dependency on chemical fertilizers, promoting long-term agricultural sustainability.

Q2: How does the use of grasses in biofuels contribute to environmental sustainability?

Answer: The use of grasses, particularly varieties like switchgrass and miscanthus, for biofuel production contributes to environmental sustainability by providing an alternative to fossil fuels. These grasses are carbon neutral, meaning that the carbon dioxide they absorb during growth is roughly equal to the emissions produced during combustion. Biofuels from grasses reduce greenhouse gas emissions compared to traditional fossil fuels, making them a cleaner source of energy. Furthermore, grasses for biofuels do not compete with food crops, as they can be grown on marginal land, thus minimizing the impact on food production.

Q3: Evaluate the impact of climate change on grass production and its consequences for agriculture.

Answer: Climate change is expected to have significant impacts on grass production, particularly through changes in temperature, precipitation patterns, and the frequency of extreme weather events. Warmer temperatures may affect the growth cycles of both forage and cereal grasses, while irregular rainfall could lead to droughts or flooding, affecting grass yield. These disruptions could lead to reduced livestock productivity due to less available grazing land and increased feed costs. Additionally, changes in grassland productivity could impact soil health, exacerbating desertification and soil erosion in vulnerable regions. Adaptation strategies such as selecting climate-resilient grass varieties, improving irrigation systems, and adopting sustainable farming practices will be essential to mitigate these risks.

Previous Year Questions on Grasses in Agriculture

1. UPSC CSE Prelims 2021:

Question: Which of the following grasses is primarily used for biofuel production?

A) Ryegrass
B) Switchgrass
C) Wheatgrass
D) Bermuda grass

Answer: (B)

Explanation: Switchgrass is one of the primary grasses used for biofuel production due to its high cellulose content and adaptability to various climates.

2. UPSC CSE Mains 2020 (GS Paper 3):

Question: Discuss the environmental benefits and challenges of using grasses in biofuels.

Answer: Grasses used in biofuel production offer several environmental benefits, including reduced greenhouse gas emissions, as they are carbon neutral. They also reduce the dependency on fossil fuels and can be grown on non-arable land, thus not competing with food crops. However, challenges include the need for large-scale land cultivation, water use, and the energy required for processing. Additionally, the long-term ecological effects of monoculture grass farming need to be assessed to ensure that it does not lead to soil degradation or biodiversity loss.