Ag science chip 17 grassland characteristics and growth

Name factors affecting grassland productivity

~ Botanical composition=the range of grasses, plants and other vegetation present

~ stocking rate= the number of animals that can be stocked on a set area of land

~ production levels= the amount of herbage produced by the pasture A high production level will lead to high production levels in livestock.(LWG)

Rough mountain or hill grazing

-land under poor quality grass

-Mountains and Hillside

-Often peaty, acidic and difficult to cultivate

-Land can be improved through liming and reseeding

Botanical composition, poorer grasses (bent grasses, fescues) Heathers and gorse are highly variable

Stocking rate nutritional levels are low-cannot support many animals

Production level low grasses are not productive

Permanent grassland

-land under grass that’s never ploughed

-can be improved with fertiliser and lime

Botanical composition variable can include productive grasses such as perennial rye grass as well as fescues and bent grasses.

Stocking rate higher than rough mountain grazing

Production level higher than rough mountain grazing since grasslands have better quality

leys

-A field or pasture sewn by the farmer

-Used for grazing by livestock

-They are temporary (weren’t a natural grassland before ) and reseded regularly

botanical composition, little or no variability usually perennial ryegrass and clover dominate which are sewn by the farmer

Stocking rate high, supports lots of livestock

Production levels high Best grasses are sewn in leys

The growth cycle of grass

1 vegetative stage

2 elongation stage

3 reproductive stage

Explain the stages of grass

1-the leaves develop on the grass plant the plant forms tillers. The plant has a slow growth rate and a low yield in this early stage.

2-the stem lengths between the upper nods plant is finished when the seedhead starts to emerge. The stem in this stage is fibrous and strong enough to support the seedhead.

3-the seed had developed wind pollination occurs and grass seeds develop as a result of pollination

Explain the growth rate of grass

• Plant that can photosynthesise and produce carbohydrate increase increases

• Growth rate increase increases

• Plant enters reproductive phase and growth rate slows and yield levels off due to the development of the seedhead

Name three characteristics of grass

Palatability

Productivity

Digestibility

Explain palatability

• How pleasant or tasty grass is for animals to eat

• Cattle and sheep are selective grazers They choose the most palatable grasses.

• If unpalatable species are present, animals leave them uneaten

• Unpalatable species continue to grow and can dominate the pasture

• Making the pastor patchy and lowering its overall quality and productivity

• For grazing animals, perennial rye grass is the most palatable grass species

Explain productivity

• The quantity of plant material produced by grass (it’s numerical)

• Higher productivity, some more grass available for livestock

• Higher stocking rates are possible when grass is highly productive

• Perennial rye grass has one of the highest productivity levels of all grass species

Explain digestibility

• The proportion of food that can be digested absorbed and used by the animal

• High digestibility= less waste more nutritents available to animal

• Grass contains protein( high digestibility) soluble carbohydrates (sugars), cellulose + fibre (low digestibility).

  Digestibility during the growing season

• Early growth/spring= high digestibility (80%) grass is mainly leafy with high levels sugars and protein

• Later growth/flowering= digestability decreases grass develop stems more fibre produced to strengthen stems protein and carbohydrates are converted to fibre. digestibility can fall from 80 to 50% in one month perennial rye grass has a higher digestibility than other grass species.

Explain dry matter

The matter remaining in a sample of food after the water has been removed

Explain dry matter digestibility

The amount (%) of dry matter that can be digested by an animal.

DM eaten - DM excreted x100

DM eaten

Explain dry matter intake

The amount of feed an animal consumes excluding its water content

DMD and grass quality

• leafy grass-high carbohydrates/protein-high DM

• Stemmy grass-high fibre-low DM

• Farmer should cut grass for solid when it’s leafy as this gives a higher DMD

• If DMD is low, the animals diet may need to be supplemented with concentrates

Give a table showing high or low for rough mountain Hill, permanent grassland, leys. each one with botanical composition, stocking rate and production level levels

Characteristics of grass idea stage of a grass plant is when the grass:

• Green and leafy

• High in soluble sugars

• High in protein

• High DMD

• Not stemmy

• Not heading out

Give a table of the DMD levels of grass during growing season with early summer and late summer and the stage, carbs and protein, fibre, digestibility

How to improve permanent grassland

• Spread fertiliser to improve soil nutrients

• Spread lime raises pH of soil

• Stitch in more white clover

• Topping remove weeds

• Spray with contact herbicide (round up)

• Reseed sow PRG and clover little bit

Describe perennial rye grass

• Spikelets

• Higher PPD

• Long growing season (reduced costs for winter feed)

• High stocking rate

• Good tillering ability

• Weed prevent

Describe Italian rye grass

• Biennial (need to be reseeded every two years)

• Longer growing season

• More heritage than PRG

• More suitable for silage production

What are the differences between white clover and red clover?

1)White clover is perennial, lacking in hairs, (glaborous), ability to fix nitrogen and protein

2) perennial, hairy (leaves and stems) ability to fix nitrogen and protein

What is ragworth

Obnoxious weed, it is poisonous for horses and cattle

How can old permanent pasture be improved?

Fertiliser, herbicide and topping

What is a seed mixture?

• Combination of different species of grass and clover or a combination of different strains of the same species of grass often mixed with clover

• Key to good grazing management is to have a constant supply of fresh grass available for grazing livestock

• It ensures that the pacer is productive through the long growing season

Advantages seed mixture for grazing pasture

~ constant supply of grass

~ fresh supply of leafy grass and high DMD

~ no dip in production levels

~ whole sword won’t go stemmy at the same time

Heading dates

The time when the year emerges on the grass plant they are categorised as early intermediate or late heading

Multi species swords (MSS)

MSS-a combination of two or more species that are sold together to increase productivity (rather than sown individually)

Grass= perennial ryegrass, Timothy

Legumes= white clover, red clover

Herbs=chicory, plantain

What are the environmental benefits if there’s all of the grass legumes and herbs and what are the disadvantages?

Environmental benefits

• Increased biodiversity

• Less poaching of soils-improved soil structure

• Less fertiliser use

• Flora and Fauna- pollination earthworms

disadvantages

• Some species will die 3 to 5 years

• Weed control-tricky (herbicides kill originally sewed specific)