
Good Grass Guide
Grassland Management
Grass is the most important, yet often overlooked, resource for livestock production. Well-managed grassland provides the most economic feed all year round. Our Good Grass Management Guide provides advice on how to get the best from your grassland, broken down into four simple step to help you manage your pasture.
Content
A selection of information guides and advice to help you with grassland management. Click below to skip to the section
Grass Plant Physiology -Learn more about ryegrass physiology and tiller leaf production.
Grass Seed Quality -Learn more about the various grass species and the difference between them
Weed Identification -We help to identify some common weeds
Grass Diseases -We help to identify some common grass diseases
Grass Pests -We help to identify some common pests that impact grass growth
Plant Physiology
In the UK, perennial ryegrass is the most widespread species of grass for grazing animals. A perennial ryegrass field is made up of a population of ryegrass tillers. A tiller is made up of a basal stem, a leaf sheath and – at any one time – three growing leaves.
When the tiller has developed three leaves it will continue to grow. As a fourth new leaf is produced the oldest leaf starts to die. Then a fifth leaf is produced and the second leaf dies – and so the process continues.
Tillers are largely individual but are clumped together, meaning they can (to some degree) exchange nutrients. The average field will contain between 3000 to 5000 tillers per square metre.
Perennial ryegrass plants will produce new tillers throughout the growing season with peak production occurring from late April to July. The time it takes for a tiller to produce three leaves will vary, depending on the plant, the local climate and the time of year.
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Ryegrass clump | Ryegrass tiller |
In mid spring it may take 15 days for a tiller to produce three leaves, with a new leaf produced every five days thereafter. In colder periods, it may take up to 50 days for a tiller to reach the three-leaf stage, with a new leaf produced every 17 days.
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Tiller leaf production |
Typically, fields grow in three phases, working in line with tiller production and energy reserves:
- The lag phase – where grass is typically less than 1200kg DM / ha
- The linear phase – where grass is typically between 1200 and 3500kg DM / ha
- The ceiling phase – where grass is typically above 3500kg DM / ha.
During the lag phase the tiller grows its first leaf; in the linear phase the second and third leaves develop; and in the ceiling phase the fourth leaf develops and the first leaf starts to die off.
When striving for peak grass performance, the aim should be to maintain grass growth in the linear phase of development, where high net growth rates and high grassland quality are achieved.
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Three phases of grassland development |
Grass Seed Quality
Important facts to consider when buying grass seed.
Few farmers would rely on genetics from the past for livestock breeding but many stick with the same grass seed varieties and mixtures year after year – even if they aren’t delivering the best results.
For some farmers, the prospect of picking a new grass can seem daunting. There are hundreds of different varieties, blends and mixtures available – so how do you know which one will work best?
If you are unsure about which product to pick, we advise selecting a grass seed from one of the UK’s Recommended Lists. Bred to perform in UK conditions, grasses included on Recommended Lists have been have been tried and tested by farmers, who’ve seen real results.
As a starting place, perennial ryegrass remains the most popular form of grass for grazing animals in the UK. But there are many other varieties that the farming sector relies on including clover, herbs and other forms of forage crops. Used in conjunction with modern grass varieties, in specially devised blends and mixtures, these can bring big yield benefits – giving animals additional essential vitamins and minerals to help weight gain, while also reducing nitrogen fertiliser requirements.
Below, we’ve put together a quick guide to the main species available, and most beneficial to UK farmers.
Species | Description | Min germ temperature |
Seeds/kg |
RYEGRASSES | All ryegrasses are capable of producing high yields of very high quality, high energy grass for cattle grazing. They are all very flexible and can be used for both cutting and grazing. They are very effective users of nitrogen but must be maintained well to maximise productivity. | ||
PERENNIAL RYEGRASS Lolium perenne |
The most popular grass used for dairy enterprises. Generally persistent for up to five years. | 7-8°C | 600,000 (dip) 290,000 (tet) |
HYBRID RYEGRASS Lolium hybridum |
Can extend the shoulders of the grazing season. Hybrid grasses are also persistent for three to five years depending on genetic capabilities and can produce up to 10% more dry matter than perennials. | 5-6°C | 450,000 (dip) 269,000 (tet) |
ITALIAN RYEGRASS Lolium multiflorum |
Generally found in short-term silage mixtures, it is a two year species that grow to temperatures as low as 3-4ºC and can extend the grazing season by three to four weeks in spring and autumn. Italian ryegrasses are capable of producing up to 20% more dry matter than perennials. | 4-5°C | 430,000 (dip) 265,000 (tet) |
WESTERWOLD Lolium mul. westerwoldicum |
Rapidly establishing annual species which gives high productivity within 12 months of sowing. This species is useful for sowing immediately after maize or cereal harvest in autumn or in spring, when high yields are required within 3-6 months of sowing. | 3-4°C | 400,000 (dip) 221,000 (tet) |
Species | Description | Min germ temperature |
Seeds/kg |
CLOVER | Clover fixes nitrogen in the soil (figures of 170-220kg N/ha/yr are achievable) - and is therefore a very valuable species in efficient grassland management. |
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WHITE CLOVER | An absolute essential for any grazing livestock system. This perennial species provides ‘free’ nitrogen, which has been fixed from the atmosphere, and can feed companion grasses. Adding white clover to grassland can increase sward digestibility, especially in the summer period. It can also improve grass protein levels and trials have proved increase intakes on grass / clover swards compared to grass alone. | 9-10°C | 1,500,000 |
RED CLOVER | Red clover is a useful plant for lactating cows and can help boost milk production but should be avoided by pregnant and breeding animals. When well managed, red clover can persist for up to five years, fixing around 50 kg N/ha/annum more than white clover. Usually sown with Italian ryegrass in short-term leys, it can also be sown with perennial and hybrid grasses to extend the lifetime of a sward by helping to suppress weeds. Red clover is typically quicker to establish than white clover although not as long lasting or tolerant of poorer conditions/management. | 9-10°C | 520,000 |
Weeds
There are lots of weeds that can invade pastures, and here we have tried to list all the ones that are relevant to grassland and pasture in the UK.
For more specific advice on how to control weeds in your grassland visit Dow Agrosciences website at http://uk.dowagro.com/product-category/grassland/
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Annual Meadow-grass is a low-growing grass which is a light green colour.
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There are 150 species of thistles worldwide, with 20 in the UK
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Favouring high-fertility sites, nettles spread through tough roots forming clumps
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Docks (Rumex spp.) are the most pernicious and damaging of all grassland weeds.
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A critical weed to be able to identify, and remove, is Ragwort. This weed is potentially deadly to livestock and is listed in the Injurious Weeds Act, which occupiers can be required by law to control. Under the Ragwort Control Act (2003), a code of practice was developed giving guidance on identification, priorities for control, methods, environmental considerations, and health and safety issues.
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Common Chickweed is the most common annual weed and can persist in rotational grass and establish in long-term pastures where there are gaps in swards due to poaching or slurry injection.
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Creeping buttercup is the most common species and is a problem in heavily grazed, poached or wet pastures.
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Grass Diseases
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Characterised by scattered orange spores over the leaves, seen in late August
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A fungal infection that produces brown spots surrounded by yellowing tissue, which is encouraged by wet and cloudy weather.
Cattle reject infected areas leading to excess growth and more disease build up.
Controlled by variety selection and excess growth management, topping grazing and encouraging new growth.
Spread by spores, wind and rain.
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Characterised by White “sappy substance” and becomes more active during the spring and autumn periods.
Spores are produced in warm, humid conditions and damage leaf area, reducing yield and palatability. Particularly susceptible plants are the faster growing ryegrasses species such at Italians.
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Brown Rust occurs early in the season, during April and May and throughout England and Wales.
It only affects ryegrasses and is a different species to the brown rusts that infects wheat and barley.
It can reach moderate levels in some varieties, but most have good resistance. |
Grass Pest Identification
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The Grey Field Slug (Deroceras reticulatum) is particularly active in wet seasons especially on the heavier soil types.
Damage is therefore most likely on direct reseeded leys. Other symptoms include shredding of the leaves of older plants. Slime trails would also be obvious. |
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The larvae of several species of chafer beetle can also cause damage to grassland in various parts of the UK. The adults are 8-10 mm long with a green head and thorax and reddish brown wing cases:
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This larva of the Frit fly (Oscinella frit) attacks all cereal and grass crops, especially those following grassy stubbles or grass.
The Frit fly larvae are yellow-whitish in colour and can grow to 5 mm long.
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Leatherjackets are the larvae of Crane-flies (Tipula spp), also known as Daddylong-legs. These soil living larvae cause considerable damage to roots and stems of many agricultural and horticultural crops, particularly of young plants.
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