Agricultural Science Lesson Note SS 2 Second Term

ENote on Agricultural Science SS 2 Second Term – Edudelight Enote

WEEK 1

PASTURE AND FORAGE CROPS

MEANING OF PASTURE AND FORAGE CROPS

Pasture refers to an area of land covered with forage crops which are usually grasses and legumes that are grazed or fed on by livestock such as cattle, sheep and goats.  Forage crops on the other hand are plants cultivated for their vegetative portions and used in fresh or preserved forms of feeding livestock.

Uses of Forage Crops

Forage crops have the following uses:

1. Livestock Feed:  Forage crops are usually used for feeding livestock like cattle, sheep and goat.  Hay, straw and sillage are prepared from forage crops
2. As Cover Crops:  Most forage crops, especially leguminous plants, serve as cover crops which add nutrients to soils and control weed growth.
3. Conservation of Soil Moisture:  most forage crops, especially leguminous plants, help to conserve soil moisture by preventing evaporation.
4. Prevention of Erosion:  some forage crops, especially leguminous plants, help to prevent water and wind erosion
5. As green Manure:  Fore crops, especially when they are young could be ploughed into the soil as green manure
6. For roofing Farmsteads:  Some forage crops like guinea grass and elephant grass are usually used for roofing farmsteads as a result of their strong stems and plenty leaves.
7. As Bedding Materials:  Most forage crops serve as bedding materials for animals.

Types of Pasture

There are two main types of pastures.  These are:

1. Natural Pasture:  Natural pasture is also referred to as natural grassland or rangeland.  In this pasture, grasses and legumes grow naturally on their own and are feed upon by farm animals, i.e., grasses are not planted by farmers.  Examples of natural grassland are the savanna areas of Nigeria.

Characteristics of Natural Pasture

1. Natural pastures of grassland contains poor quality grasses and legumes
2. It contains soil types that are low in fertility
3. It contains wide varieties of grasses and legumes, some of which may not eaten by livestock
4. It has good regenerative ability
5. Productivity of natural pasture is very low and resistant to drought
6. Forage crops in natural pasture can withstand trampling by farm animals.
7. Natural pasture may contain some grasses which cannot be easily eradicated
8. New growth is stimulated by burning
9. Artificial Pasture:  This is also referred to as established or sown pasture.  In this pasture, grasses and legumes are deliberately planted and managed by man to be fed on by livestock.

Characteristics of Artificial Pasture

1. It contains high quality grasses and legumes
2. It contains no weeds except some shade trees
3. Selected grasses and legumes are grown in adequate proportion
4. It has high regenerative ability after being fed on by animals
5. It can withstand trampling by farm animals
6. It is properly managed for high productivity of the forage crops e.g. fertilization, irrigation and rotational grazing.

COMMON GRASSES AND LEGUMES OF LIVESTOCK AND THEIR BOTANICAL NAMES

Grasses:

Common Name                     Botanical Name

(1)  Elephant grass                  Pennisetum purpureum

(2)  Guinea grass                     Panicum maximum

(3)  Giant Star grass                Cynodon plectostachyum

(4)  Carpet grass                      Axonopus compressus

(5)  Spear grass                       Imperrata cylindrical

(6)  Bahama grass                   Cynodon dactylon

(7)  Northern gamba                Andropogon gayanus

(8)  Sourthern gamba              Andropogon tectorum

Legumes:

Common Name                    Botanical Name

(1)  Centro                             Centrosema Pubescens

(2)  Stylo                               Stylosanthes gracilis

(3)  Kudzu or puero               Pueraria phaseoloides

(4)  Calopo                            Calopoganium mucunoides

(5)  Muccuna                         Muccuna utilis

(6)  Sun hemp                        Crotalaria juncea

FACTORS AFFECTING THE DISTRIBUTION OF PASTURE

Factors affecting the distribution of pasture can be grouped into three classes:

1. Climatic Factor:  The type of climate in an area influences the type of vegetation in that particular area.  For example, Sudan types of climate favours the growth of grasses and legumes while Equatorial climate does not.  Elements of climate which can directly influence temperature, relative humidity, day length, sunlight, etc.
2. Soil or Edaphics Factors:  This refers to the level of fertility of the soil.  Fertile soil tends to support pasture growth while poor soil does not.  Soil factors which may influence the distribution of pasture are soil pH, soil texture, soil structure as well as the slope of the land (topography).
3. Biotic Factors:  Biotic factors like disease, pests, parasites, predators generally influence the distribution of pasture.  The activities of man such as bush burning and over-grazing generally have adverse effects on the distribution of pasture

FACTORS AFFECTING THE PRODUCTIVITY OF PASTURE

These factors include:

1. Persistence:  This is the ability of the pasture crops to survive and spread by vegetative means.
2. Aggressiveness:  This is the ability of pasture to compete favourably with other weeds.  High aggressiveness ensures continous availability of the pasture crops.
3. Resistance to Trampling:  This refers to the ability of pasture to resist continuous trampling by farm animals during grazing and still remains available to livestock to feed on.
4. Seed Viability (or profuseness):  Seeds of pasture should be viable over a long period of time.  It should be easily propagated to ensure high pasture productivity
5. Pests and Disease:  Absence of pests and disease within a pasture ensures their increased productivity
6. Accurate Stocking:  An accurate number of animals should graze a specified area of pasture.  Overgrazing does not ensure increased productivity of pasture.
7. Good Management:  Proper management practices such as regular weeding, rouging, irrigation, good grazing, fertilization, etc. should be practiced to ensure increased productivity of pasture.

ESTABLISHMENT OF PASTURE

Before pasture can be established, the following factors should be considered:

1. Adaptation of Species:  Legumes and grasses should be adapted to the local environment
2. Palatability:  Legumes and grasses to be established must be palatable and nutritious for animals.
3. Compatibility:  The grass-legume mixture in the pasture must be compatible to each other
4. Time of Maturity:  grasses and legumes to be established should be able to mature within the shortest possible time
5. Life Cycle of the Species:  Annuals with annual plants or perennials with perennials plant should be mixed together when establishing pasture.  This is to ensure continous availability of pasture

The establishment of pasture takes the following sequence:

1. Site Selection:  Select a suitable site which should be well-drained with good loamy soil.
2. Clearing of Land:  The land should be cleared or cut back the site with hoes and cutlasses.
3. Removal of Debris:  Debris on the site should be removed or it could be gathered and burnt.
4. Cultivation of Site:  The land, field or site should be cultivated by way of ploughing, harrowing and if possible ridging
5. Planting of pasture crops:  Planting of the desired pasture, grass or legume is carried out.
6. Supplying:  Plant materials that fail to germinate should be supplied with new planting materials
7. Planting of Legumes:  Leguminous plants should be planted, especially in the case of grass and legume mixture
8. Promotion of Tillering:  The grasses should be cut back at regular intervals to promote tillering.
9. Weeding:  Weeding should be done at regular intervals, especially at the early stages of the pasture
10. Fertilizer application:  Apply fertilizers at the appropriate rate by broadcasting
11. Irrigation:  Light irrigation or watering of the planted seeds or solons should be done, especially in arid areas with low rainfall.
12. Paddocking:  The pasture should be broken into convenient units for good grazing management like rotational grazing

COMMON MANAGEMENT PRACTICES IN PASTRUE

Some common management practices in pasture to ensure continous supply of grasses and legumes to livestock include the following:

1. Burning:  Burning should be done once in a year, especially when the forage crops are over-regrowth of the grasses and legumes
2. Fencing:  This is the partitioning of the pasture into sections called paddocks to facilitate rotational grazing
3. Application of fertilizer:  Application of fertilizer in the pasture ensures rapid and succulent growth of pasture because of increase in the fertility of the soil
4. Weed control:  Weeds should be removed regularly from the pasture to prevent competition with forage plants for nutrients and space
5. Pests and Diseases control:  These should be prevented to ensure rapid growth of pasture crops
6. Irrigation:  Pasture farm should be irrigated, especially during the dry season to ensure the availability of fresh and succulent grasses all the year round.
7. Adequate stocking:  The correct number of animals should be placed on a pasture to graze.  Overgrazing should be prevented.

WEEK 2

FOREST MANAGEMENT -ENOTE

MEANING OF FOREST, FORESTRY AND SILVICULTURE:

Forest can be defined as a large area of land covered with trees and bushes, either growing wild or planted for some purpose.  While forestry is the art of planting, tending and managing forests, including the utilization, tending and managing forest, including the utilization of their products, silviculture is the study of forest trees and other related trees.

Common Forest Trees

Common trees usually found in the forest are Iroko, Obeche, Mahogmay, Sapele, Nigerian walnut, Ebony, Camwood, Opepe, Afara, Teat, Abura, etc.

Forest Reserves in Nigeria

Meaning of Forest Reserve:  Forest reserves are large areas of land where pants either growing naturally or panted are specially preserved by government for specific purpose.

Some forest reserves in Nigeria are:

1. Mamu river Forest Reserve in Anambra State
2. Omo Forest Reserve in Ogun State
3. Afi River Forest Reserve in Cross River State
4. Okomu Forest Reserve in Edo State
5. Anara Forest Reserve in Kaduna State
6. Shasha River Forest Reserve in Ogun State
7. Sakpoba Forest Reserve in Edo State
8. Zamfara Forest Reserve in Zamfara State
9. Sanga River Forest Reserve in Plateau State
10. Awba Hills Forest Reserve in Oyo State.

Importance or Uses of the Forest

Forest is very important for several reasons.  It is very important for government to encourage the planting of trees because of its usefulness in the following ways.

1. Provision of Food:  Forest including savanna provides food such as fruits, bush meat, vegetable, etc.
2. Provision of Fuel:  Dead forest wood serves as firewood or source of fuel used for cooking and other purposes
3.  Provision of Medical Herbs:  The forest also provides medicinal herbs used by local healers and pharmaceutical industries
4. Provision of Employment:  Forest provides employment to some people, e.g., forest guards and those involved in lumbering
5. Forest Serves as Wind-break:  Forest, especially in the Northern part of Nigeria, serves as wind-break, thereby reducing the speed of wind and controlling wind erosion
6. Formation of Rain:  Forest, because of their cool environment, help in the condensation of water vapour, result in the formation of rain
7. Prevent of Soil Erosion:  forest helps to absorb water splash on the soil and also due to vegetative cover, soil erosion is prevented
8. Addition of Nutrient to Soil:  Forest adds nutrients or improves the fertility of the soil through the decay of fallen leaves
9. Home of Wild Animals:  Forest serves as the home of all wild animals like lion, tiger, antelope, rabbit, snakes, etc.
10. Forest Serves as Tourist Centres:  Forest, because of its beautiful scenery, does serve as tourist centre.
11. Provision of Foreign Exchange:  Forest provides foreign exchange earnings for the country through the export of timber and its by product
12. Provision of Timber:  Forest provides timber for furniture and other domestic and industrial constructions
13. Provision of Pulp:  Forest provides pulp used for tissues and paper making
14. It beautifies the Environment:  Forest trees planted around homes, industries and offices help to beautify the environment
15. Reduces Atmospheric Pollution:  Forest help in the purification of the air by removing carbon dioxide and adding oxygen to the atmosphere during photosynthesis.
16. Sources of Raw Materials:  Forest provides raw materials such as gum, resins, ropes, dyes, firbes, rubber, palm produce, oil seeds for both domestics and industrial purposes.

MANAGEMENT OF THE FOREST

In order to ensure the continuous supply of timber from the forest, the following management practices should be adopted:

1. Forest regulations;
2. Selective exploration;
3. Deforestation;
4. Regeneration;
5. Afforestation;
6. Taungya system.

Forest Regulations

These are laws promulgated by government in the form of edicts, decrees and bye-laws to prevent from exploiting or indiscriminate tapping of forest resources.  These regulations, therefore, ensure the preservation of forest resources

Forest regulations in Nigeria include:

1. The prohibition of bush burning
2. Ban on indiscriminate cutting of timber trees
3. Encouraging people to plant tress
4. Ban on collection of leaves and firewood from the trees
5. People are to obtain license so as to secure the permission to enable them to cut down trees for human needs.  The felling quantity should be based on the number of forest stands which must be determined before felling.

Selective Exploration

Selective exploration is the process of cutting or harvesting only mature trees in a forest.  It is a way of concentrating certain selected species of timber in a forest reserve.  The system allows for the harvesting or older trees while the younger ones remain as cover to the surface of the forest.

Advantages of Selective Exploration

1. It ensures the concentration of selected species of timber in a forest
2. It protects the soil from erosion
3. It ensures the continous supply of timber
4. It serve as a revenue base for the government
5. It prevent indiscriminate felling of timber by giving license to saw millers by state forestry division
6. It also prevents illegal felling of trees and farming by using forest guards to police the forest.
7. Undesirable species of timber are eliminated by this method.

Deforestation

Deforestation is the continuous removal of forest stands (trees) either by bush burning or indiscriminate felling without replacing them.  Economics trees such as Iroko, Obeche, Mahogamy, etc are cut down so that they can be used for various purposes such as furniture like tables, chairs, doors, etc. uncontrolled deforestation should never be allowed.   The rate of deforestation should be reduced to the barest minimum because of its adverse effects.

Causes of Deforestation

Deforestation can be caused for many reasons which include:

1. Unfavourable Climate Factors:  Persistent and prolonged drought can lead to death of forest species.  Also, wind blast can destroy vegetation on its path
2. Man’s Farming Activities:  Man’s farming activities can cause forest destruction through the sued of forest land for crop production or grazing livestock, practicing of bush fallowing or shifting cultivation which progressively leads to deforestation because the short fallow periods do not allow for sufficient forest regenerations
3. Timber Exploitation:  the practice of selective elimination of certain tree species in a natural forest causes deforestation.  Also, the exploitation of timber for furniture, export, etc., can cause deforestation
4. Mining/industrialization:  forest trees are destroyed when the land is cleared for excavation for mining minerals.  Also, petroleum exploration and sitting of industries involved clearing of forest
5. Natural disasters:  fire is the most serious problem to which forests are exposed, especially during the dry season.  Bush burning is caused by fire used by farmers.  Such fire may extend to the forest, thereby destroying tree species. Other natural disaster which can cause deforestation include landslide, earthquakes, volcanic eruptions and prolonged flooding.
6. Government Policies:  Government inadvertently introduces policies that can encourage felling of fuel woods and timber exploitation.

Effects or Disadvantages of Deforestation

Deforestation has come effects or disadvantages on the environment.  These are:

1. Deforestation encourages or increases soil erosion
2. It leads to loss or organic matter, resulting in the loss of soil fertility
3. It reduces the amount of rainfall in the area, or, it causes the destruction of watershed.
4. It decreases soil moisture retention
5. It increases the leaching of plant nutrients
6. Deforestation destroys the micro-climate, and warms up the environment.
7. It also reduces the forest fauna (wild life) population in the area concerned.
8. It may lead to desert encroachment as sand particles are more likely to drop in areas without trees.
9. It depletes the supply of forest produce (raw materials) to industries, e.g., timber.

Regeneration

Regeneration is the process of forest regrowth after it has been exploited.  It is a deliberate government policy in the restoration of deforested area after exploitation to balance the ecosystem.

Types of Regeneration

There are two main types of regeneration

These are:

1. Natural Regeneration:  in natural regeneration, there is regrowth of new plants from old stumps.  Under favourable environment, there exists the growth and development of new tree or volunteer trees form old stumps.
2. Artificial Regeneration:  This involves the natural planting of new forest seedling in a deforested area.  In other words, forest trees are established deliberately in a plantation.

Advantages of Natural Regeneration

1. It is less expensive when compared with artificial regeneration
2. It does not require formal stages in plantation establishment
3. It brings about the stabilization of natural ecosystem in the area of its establishment
4. It does not require special management skill

Afforestation

Afforestation is the process of establishing forest plantations in any area. It involves the complete removal of natural vegetations before planting new forest species.  In Nigeria, it is popularly referred to as tree planting campaign in which two seedlings of trees are recommended to be planted to replace any one plant harvested.  Early stages of afforestation may include taungya farming (which is the planting of trees and crops on the same piece of land) to maximize the use of land and protect seedlings.

Advantages of Afforestation

Afforestation has many advantages:

1. It leads to addition of organic matter resulting in an increase in soil fertility
2. It provides a regular supply of raw material, e.g., timber for industries
3. It prevents desert encroachment
4. It increases the forest fauna (wild life) in the area concerned
5. It builds-up the micro-climate and cools up the environment
6. It prevents the leaching of plant nutrients
7. It increases soil moisture retention
8. It increases the amount of rainfall in the area.
9. It helps to build-up the soil structure

Taungya System

Taungya system involves the planting of both food crops and forest trees on the same piece of land.  In other words, it is a system which involves the integration of agriculture with forestry.

Conditions Necessary for the Practice of Taungry System

The conditions that may favour the practice of taungya system include:

1. Scarcity of Land:  Taungya system can easily be practiced where land is scarce
2. Over-population:  Land becomes scarce where there is over-population which can lead to the practice of the system.
3. Unemployment:  Mass underemployment or unemployment does lead people to practise taungya system
4. Government policies:  Government can put in place policies which will make people practise taungya system.
5. Low Standard of Living:  this factor does force people to resort to the practice of taungya system as a means of alternative way of increasing their standard of living
6. Granting of incentive:  Incentives such as loans to farmers can helps them to take part in additional farming.

Advantages of Taungya farming

1. Variety of crops are harvested
2. There is the availability of crop produce throughout the year
3. When leguminous crops are sued, the beneficial effect of root nodules increases soil fertility for the benefit of the forest trees.
4. Where land is scarce, the farmer ahs a piece of land to cultivate
5. The young forest trees receive direct and indirect attention form the farmer
6. It increases the income of the farmer

Farmer’s Benefits

Farmers derive the benefit of:

1. Using available fertile land for farming
2. Increases standard of living
3. Accessibility to forest products, e.g, dry wood for fuel
4. Employment of farmers in plantation activities other than initial raising of forest crops

Foresters derive the benefit of

1. Reduced cost of establishment plantation
2. More land is under forest cover
3. Weed control
4. Enrichment of soil nutrients when leguminous food crops are planted

Disadvantages of Taungya farming

1. Reluctance in Releasing Fertile Soil:  the forestry sector may be reluctant in releasing their fertile land to the agricultural sector for farming.
2. Cultivation of Selected Crops:  The system only allows the farmers to rear animals and cultivate biennial crops in the forest reserves.
3. Competition Between Crops and Trees:  Since crops and trees are grown together on the same piece of land, competition for space, water, nutrients, etc. will exist between crops and forest trees.
4. Monotony of Operations:  The practice of taungya farming may be monotonous as the farmer performs the same operations every season.
5. Inability of Some Crops to Survive:  most crops cultivated under taungya farming may not survive due to the invasion of some insects in the forest reserve.

WEEK 3

FLORICULTURE

MEANING OF FLORICULTURE

Floriculture is simply defined as the cultivation of flowering plants.  In other words, floriculture involves the growth, care, uses and marketing of some flowering plants, trees and shrubs.  Beautiful trees or flowering plants which can be used to decorate our environments are called ornamental plants.  Ornamental plants could be trees, shrubs or flowers.

The person who grows or sells flower is called florist.

Importance/Uses of Ornamental Plants

Ornamental trees, shrubs and flowers are very important in a number of ways.  These include:

1. For Interior Decoration:  Some beautiful flower are used to decorate the interior of residential, commercial and industrial building.
2. For Exterior Decoration:  Some flowers are also used to decorate the exterior of residential, commercial and industrial buildings, making such flowers to add beauty to the environment.
3. For landscaping:  Many beautiful flowers are used for landscaping by florist.  It may involve the writing of some wording, using flowers.
4. Decoration of avenues and Resort Centres:  Flowers are also used to decorate city centres, round-about, route junctions, and resort centres.
5. Decoration of Roads:  Many roads are often decorated with beautiful flowers.  Such flowers add beauty to the design of such roads.
6. Preparation of Perfumes:  Some perfumes can be prepared from flowers.  For instance, morning glory flowers can provide natural perfume to home and offices, especially in the morning and evening
7. For Scientific Research:  Many flowers are used by florists, scientists, etc. for scientific studies in botanical gardens.
8. Provision of Shade: Some flowering plants have large and broad leaves which are capable of providing shade in residential or industrial environments.
9. For Ceremonial Use: Some beautiful flowers are used in certain ceremonies, e.g, wedding, burial, etc.
10. As Symbol of Love: People often use or given beautiful flowers to their partners, friends or relations as a symbol of love and affection.
11. Sources of Local Herbs: Some ornamental plants can be used as sources of local herbs.
12. Sources of Income to Florists: Ornamental plants and flowers also provide income to horticulture or florists.
13. Noise absorption: Some specific flowers and ornamental plants are used in noise absorption.
14. Purification of Atmospheric Air: Ornamental plants including other plants help to purify atmospheric air by removing carbon dioxide and releasing oxygen.
15. Provision of Employment: Employment is provided through the cultivation of flowers, e.g, for gardeners.
16. Provision of foreign Exchange: Some beautiful flowers and ornamental plants provide foreign exchange to the government when exported.

Common Species of Ornamental Trees, Shrubs and Flowers

Some common species of ornamental trees, shrubs and flowers include:

Ornamental Trees

1. Frangi pani
2. Neem cassia
3. Royal palm
4. Balsam
5. Flame of the forest
6. Indian almond
7. Casuarinas
8. Delonix

Ornamental Shrubs

1. Allamanda
2. Crotons
3. Ixora
4. Cauliflower
5. Acalypha
6. Hibiscus
7. Wild rose
8. Bougainvillea
9. Zinnia
10. Dutchman’s pipe

Ornamental Flowers

1. Justicia
2. Canalily
3. Morning glory
4. Crotalaria
5. Sun flower
6. Marigold
7. Commelina
8. Clitoria
9. Water lettuce
10. Lantana
11. Passion flower
12. Gloriosa.

CULTIVATION OF ORNAMENTAL TREES AND FLOWERS

Ornamental trees and flowers are better cultivated through a number of cultural practices in order to enhance good production and high quality of flowers.  The cultivation of ornamental flowers includes:

1. Choice of Site: The site should be well drained and easily accessible to the florists and customers.  Water should easily be available for watering of flowers.
2. Planting Materials: Planting Materials include seeds, vegetative propagation through cut stems, roots, leaves (e.g Bryophylum), stolons, etc.
3. Methods of Cultivation: Ornamentall trees and flowers can be grown through any of the following methods:
4. Use of Prepared Beds: This serves as nursery beds where the young seedlings of flowers are raised
5. Direct sowing to Soil:  Seeds or stem cutting can be sown directly into soil where they sprout to become flowers
6. Use of Nylon Bags:  Seeds or stem-cuttings can be sown directly into nylon bags containing soil from where they can grow up before transplanting.
7. Use of Pots:  Seeds or stem-cutting can be sown directly into clay pots, containing loamy soil from which flowers can grow.

iv.        Provision of Shade:  Shade should be provided for the seedlings to protect them against excessive rainfall and heat of the sun.

v.         Use of Loamy soil/Organic Manure:  Soils in which seeds or stem-cuttings are to be planted should be loamy soil because it is very fertile.  Some organic manure, e,g., farmyard manure can be added to the soil to improve its fertility.

vi.        Regular Watering:  Flowers should be watered at least twice a day – morning and evening.

vii.       Regular Weeding:  The florist should ensure that unwanted plants (weeds) are removed so as to provide nutrients, space, light, ect, for the normal growth of ornamental trees and flowers without competition.

SOURCES OF PLANTING MATERIALS

Source of planting materials like seeds, cut stems, leaves, stolons or rhizomes, etc, include;

1. Establishes private horticultural gardens
2. Higher institutions’ botanical gardens
3. Government-owned horticultural centres
4. Private houses and offices
5. Imported ornamental trees and flowers
6. Resort or recreational centres

Maintenance of Horticultural Plants/Flowers

1. Provision of  Shade:  Shade should be provided for the seedlings to protect them against excessive rainfall and heat of the sun.
2. Regular Watering:  Horticultural plants and flowers should be watered at least twice a day-early in the morning and late in the evening.
3. Regular Weeding:  The florist should ensure that unwanted plants (weeds) are removed so as to allow for adequate nutrients, space, light, etc, for the normal growth of ornamental trees and flowers.
4. Fertilizer Application:  Fertilizers and manure can be applied to the soil to improve the soil fertility for the growth of ornamental trees, shrubs and flowers.
5. Fencing:  Ornamental plants should be protected from being eaten up by animals like cattle, sheep, goat, etc.
6. Regular Pruning:  Old leaves, stems and side branches should be pruned with either shears or secateurs.

WEEK 4-5

RANGE AND PASTURE MANAGEMENT AND IMPROVEMENT

MEANING OF RANGELAND AND PASTURE

A Rangeland is an extensive area of land which contains forage grasses and legumes and other herbage plants where animals like cattle, sheep and goat can graze.  The forage plants such as the grasses and legumes used for grazing by the farm animal are called Pasture.

IMPORTANCE OF RANGELAND

1. Rangeland provides food for livestock, especially ruminants.
2. Grasses and legumes in the rangeland, when cut at early flowering stages of growth, can be preserved in the form of hay or silage.
3. Rangeland allows animals to exercise their body.
4. The animals have access to varieties of forage, thus, eating balanced feed.
5. Rangeland reduces the cost of feeding animals, especially ruminants
6. Rangeland increases infiltration and percolation of water, thereby reducing run off and soil erosion
7. Dead plant materials from rangeland build up the fertility of the soil
8. Rangeland affords animals the opportunity for mating without the supervision of the livestock attendant
9. Rangeland also provides adequate nutrients to the soil through legumes which fix nitrogen into the soil by the bacteria in their root nodules.

CHARACTERISTICS OF RANGELAND

1. It contains high quality grasses and legumes
2. It contains no weed except some plant for shades
3. Selected grasses and legumes are growth in adequate proportion
4. It has a high regenerative ability after being fed on by animals
5. It can withstand trampling by farm animals
6. It is property managed for high productivity of the forage crops, e.g, fertilization, irrigation and rotational grazing.

COMMON GRASSES OF LIVESTOCK IN RANGELAND

Common Name                     Botanical Name

(1)  Elephant grass                  Pennisetum purpureum

(2)  Guinea grass                     Panicum maximum

(3)  Giant Star grass                Cynodon plectostachyum

(4)  Carpet grass                      Axonopus compressus

(5)  Spear grass                       Imperrata cylindrical

(6)  Bahama grass                   Cynodon dactylon

(7)  Northern gamba                Andropogon gayanus

(8)  Sourthern gamba              Andropogon tectorum

common Legumes of Livestock in Rangeland

Common Name                    Botanical Name

(1)  Centro                             Centrosema Pubescens

(2)  Stylo                               Stylosanthes gracilis

(3)  Kudzu or puero               Pueraria phaseoloides

(4)  Calopo                            Calopoganium mucunoides

(5)  Muccuna                         Muccuna utilis

(6)  Sun hemp                        Crotalaria juncea

FACTORS AFFECTING THE LEVEL OF PRODUCTION OF HERITAGE

Factors which affect the level of productivity of herbage include:

1. Rainfall:  Rainfall is needed for the continous growth of grasses and legumes.  Rainfall helps to dissolve nutrients and makes it available to pasture plants
2. Grass and Legumes Mixture:  Pasture or rangeland should include a mixture of grasses and legumes because legumes help to increase the fertility of the soil for rapid growth of the grasses.
3. Grazing: The range should be carefully planned to ensure adequate grazing by animals.  Rotational grazing should be adopted to provide opportunity for the grazed plants to regenerate.  Overgrazing, a condition whereby there are too many animals on a piece of grassland feeding on the herbage should be avoided.
4. Removal of Trees:  Trees within the rangeland should be cut off since they can provide shade that might prevent grasses and legumes from receiving adequate sunlight.  This can reduce the productivity of herbage
5. Fertility of the Soil:  The soil on which herbage plant grows must be fertile so that their production can be enhanced
6. Control of Weeds:  For herbage plants to improve their productivity weeds must be removed from the rangeland and regularly, since they compete with herbage plants for nutrients, space, sunlight, etc.
7. Avoidance of Overstocking:  The correct number of animals should be allowed to graze a specified area of pasture.

MEHTOD OF RANGELAND AND PASTURE IMPROVEMENT

To ensure the continous availability of grasses and legumes, it is necessary to adopt some management principles that would lead to the improvement of rangeland and pasture.  Such principles include:

1. Controlled Stocking:  This refers to the situation whereby the correct numbers of animals are allowed to graze a particular area of land.  An adequate stocking rate should be maintained as overstocking could lead to deterioration of the rangeland.
2. Reseeding:  This involves replanting of seeds of forage crops on a depleting rangeland. When animals have grazed a lot of rangeland, the crops may start to show signs of dying off, and then reseeding becomes necessary.  The farmer should improve on the range by broadcasting new seeds and allowing the rangeland to rest.  Reseeding is most beneficial where rotational grazing is practiced.
3. Legume and Grass Mixture:  In natural grassland without legumes, the farmer may improve it by introducing legume seed into the rangeland.  Legumes provide protein for animals and also add nutrients to the soil.  Once the legumes and grass mixture has been established, it should be maintained.  Legumes such as: pueraria, centrosema, stylosanthes, etc, can be used.
4. Paddocking:  Paddocking involves dividing the rangeland into a number of sections with fences.  The animals normally feed on each section on a rotational basis.  This allows for good regeneration of forage crops and prevents the pest and disease build-up.  While the animals are grazing on one section, others will be at rest. The farmer may cut forage for hay and silage from the resting rangeland.
5. Avoidance of Overgrazing:  Overgrazing involves constant grazing and cutting of forage crops such that the crops start to die and the land becomes bare.  Overgrazing and overstocking should be avoided as it leads to the destruction or rangeland and erosion.  It also leads to overgrazing and soil pulverization.
6. Use of Fertilizers:  Fertilizers should be applied to rangeland plants.  This ensures enough foliage formation for grazing and silage preparation. Compound fertilizers e.g., NPK should be applied once every year or two.
7. Pest Control:  In order to destroy some pests of crops and animals, it may be necessary to spray the rangeland with suitable pesticides.  This ensures that the rangeland is pest-free.  It reduces the rate of disease spread.
8. Controlled Burning:  This aids regeneration of forage crops.  It also sanitizes the rangeland, i.e, by getting rid of weeds, seeds, disease organism and pest.  It adds some nutrients e.g potassium to the soil
9. Irrigation:  Rangeland should be irrigated especially during dry season to ensure an all year round availability of fresh and succulent grasses.

WEEK 6-7

DISEASE AND PESTS OF CROPS

MEANING OF DISEASE

A plant disease may be defined as a departure or deviation of the plant from the normal state of health, presenting marked symptoms or outward visible signs.

Causes of Diseases

Diseases are caused by the following agents:

(i)  Viruses  (ii) Bacteria  (iii) Fungi  (iv) Nematode  (v) Nutrient deficiency

SELECTED DISEASES OF CROPS

Name of Disease	Causal Organism	Method of Transmission	Symptoms and Economic Importance	Prevention and Control Measures
Maize Snut	Fungus (ustilago maydis)	Air borne Fungus spores deposited on fruits	Reduced yieldGalls on ears, leaves and tarsels which later turn black	Destroy diseased plant. Use resistant varietiesSeed treatment.
Rice Blight	Fungus (piricularia oryzae)	Airbone spores on leaves	Small longitudinal red spots on leaves which turn	Use clean seedsAvoids heavy use of nitrogen fertilizersUse resistant varieties
Maize Rust	Fungus (puccinia polysora)	Airborne spores deposited on leaves	Red spots on leavesReduced yieldDeath of the crop	Early plantingCrop rotationUse resistant varieties
Cercopora a leaf spot of cowpea	Fungus	Thr20ough wild	Reddish brown spots on leavesLesions on leavesChlorosisDropping or falling of leaves	Spray with fungicides Crop rotationPlant resistant varieties
Rosette disease of groundnut	Virus	By piercing and sucking insect (Aphid).	Yellow leaves with mosaic mottling.Stunted plant with curled leaves.Wilting and death of plantShortening of the internodes	Early plantingCrop rotationUse insecticidesUproot and burn infected plantsUse resistant variety.
Cassava Mosaic	Virus	Through piercing and sucking insect (whitefly) (Bemisia nigerensis)Infected plant cutting	Mottling of leavesMosaic pattern on leavesStem/leaf distortionStunted plantReduction in yield	Use resistant varietiesUproot and burn infected plantSpray with insecticides to kill vectorUse disease free stem cuttingFarm sanitation.
Leaf blight of cassava	Bacterium xanthomonas manihotis	Infected cuttingRain splashingInsectsTools	Blighting  of leaves Wilting of plantFalling off lf leavesReduced yieldCanker of stemDie-back of stem	Use resistant varietiesUse disease free cuttingEarly plantingPractise crop rotation
Cocoa black pod disease	Fungus phytophthora palmivora	Rain splash Insects	Brown spots on podRottening of pods.Entire pod turns blackLow yield	Remove and destroy infected pods.Regular weedingSpray with fungicides e.g. Bordeaux mixture.Avoid overcrowding of cocoa plant.
Coffee Leaf rust	Fungus	By windBy rain splash	Yellow or brown spot on leavesOrange powdery mass on the leafReduction in yieldDropping of leaves	Plant seeds from healthy plants.Use resistant varietiesSpray with copper fungicides
Black arm (bacterial blight of cotton)	Bacterium	Through leavesStems near the ground	Angular spots on leavesBoll rotExudates from affected leavesRetarted growth and death of plant	Seed dressingUproot and burn infected plantsUse resistant varietiesCrop rotation
Root knot of tomato/okro Damping off disease of okra	Nematode     Fungus	Nematodes in soil     Infected soil	Knotting or galling or rootsRetarded growthEarly death of plantReduction in yieldRetarted growthCells becomes water loggedGradual wilting of plantsDeath of plant	Soil sterilizationCrop rotationUse resistant varieties Uproot and burn infected plantsSpray with copper fungicideUse resistant varietiesSterilization of soil
Onion twister disease	Fungus	Infected soilWater splashInfected bulb.	Twisting of leavesGrey patches on leavesReduction in yieldDeath of plant	Crop rotationUse resistant varietiesSpray with fungicidesEarly planting
Stored produce mould	Fungus	Infected seed or fruitsHigh humidity By soil	Black mould on seeds and fruitsPungent smellSour tasteDecay of seeds and fruits in store	Proper drying of seed before storageSpray with fungicides Maintain low humidity in storeRemove contaminated seeds before storage.

GENERAL EFFECTS OF DISEASES ON CROP PRODUCTION

Disease cause lots of damage of crop and their effects are as follows:

1. Disease generally reduce the yield or productivity of crops
2. They also reduce the quality of crops
3. They cause the malformation of plants or the whole plants
4. They can kill or cause the death of a whole palnt
5. They cause reduction in the income of the farmer
6. They increase the cost of production through the expenses incurred in the course of controlling them
7. The render vegetables and fruits unattractive and unmarketable
8. Their activities cause retarded growth in crop plants

Ways by which diseases spread on a crop farm

Diseases can spread on a crop farm through any of the following ways:

1. By rain splash
2. Through the use of contaminated tools and equipment
3. The use of infected planting materials
4. Wind blowing pathogens to other crops
5. Through animals, especially predator during feeding
6. Through insect vector
7. Through visitors to the farm
8. Through weeds which may harbor pathogen
9. Through irrigation water.

GENERAL CONTROL OF CROP PLANT DISEASES

Diseases of crop plans can be controlled by the following methods:

(1)  Cultural control;  (2) biological control:  (3) chemical control.

1. Cultural Control:  This involves the use of crop rotation, resistant varieties, tillage practices, regular weeding, fallowing, timelines of planting, pruning, uprooting and burning of infected plant, soil treatment or sterilization, rouging or uprooting of infected crops, maintenance of farm hygiene, timeliness of harvesting, etc. to control or prevent diseases.
2. Biological Control:  This involves the use of natural enemies of the disease to reduce or totally eliminate the disease
3. Chemical Control:  This involves the use of chemical such as fungicides, nematicides, insecticides to dust or spray plants and plant materials in order to prevent or control plant disease.

Summary of General Control Measure of Diseases of Crops

1. Weed the farm regularly to prevent the disease pathogens from being haboured by weeds.
2. Practise crop rotation
3. Remove and burn infected plants
4. Plant disease-resistant varieties of crops
5. Use healthy seeds or stems for propagation
6. Practise seed dressing with plant protection chemicals such as Fermassan D before planting
7. Spray plant protection chemicals such as fungicides and nematicides
8. Early planting helps the crops to escape the period of disease occurrence
9. Spray insecticides to control the insect vectors
10. Destroy crops’ residues after harvesting to prevent the build-up of disease pathogen or practice good farm sanitation or hygiene
11. Sterilize soil to control soil-borne diseases
12.  Avoid close planting to reduce the rate of spread of diseases
13. Imported seeds and plants should be quarantined before their introduction into the country
14. Timely harvesting reduces the period of exposure

WEEK 8-9

MEANING OF CROP PEST

A pest can be described as any organism capable of causing damage to crop plant.

Types of Crop Pest.

Important pests of crop plants are grouped into the following classes:

(i) insect;  (ii) birds;  (iii) rodents;  (iv) monkeys;  (v) man;  (vi) nematodes

CLASSIFICATION OF INSECT PESTS

Insects pests can be classified into various groups based on their mode of feeding.  These groups of insect pest include:

1. Bitting and chewing insects;
2. Piercing and sucking insects;
3. Boring insects.
4. Biting and Chewing Insects:  These insect (mouth-parts) which enable them to bite and chew plant  parts.  Examples include: termites, grasshoppers, leaf worms, army worms, mantids, locust, beetles, etc.
5. Piercing and sucking insects:  These insect pests posses strong mouthparts called proboscis stuck liquid from materials from plants’ tissues.  Examples include aphids, cotton strainers, mealy bugs, scale insects, capsids or mirids, white flies, etc.
6. Burrowing insects:  These insects including their larvae are capable of burrowing into plant parts and destroying the tissues of the plant or fruits or seeds.  Examples include: bean beetles, stem burrowers, maize weevils and rice weevils.

IMPORTANT PEST OF MAJOR CROPS

Insect Pest	Crops Attacked	Nature of Damage and Economic Importance	Prevention and Control Measure
Stem burrower	Cereals e.g. rice, maize, guinea corn	Larvae bore holes into stems.They eat up the plantThey weaken the plant Reduced growth and yield	Uproot and burn infected plant.Spray with insecticides e.g. Gammlin 20.Early plantingCrop rotation.
Army Worm	Cereals e.g. maize	Larvae invade and eat up leaves and stemReduce photosynthesisRetarded growthReduced yield	Hand picking Spray with insecticides e.g. DDT.
Pod Burrower	Legumes e.g. cowpea, soyabeans	Larvae bore into the pod.They eat up the seeds.Reduced yield Introduce disease	Crop rotationEarly harvestingSpray with insecticides
Aphids	Legumes e.g cowpea, soyabeans	Stunted growthGalls on leavesVectors of disease e.g. rosette, mosaic disease of cowpea	Spray with insecticides to kill vector Uproot and burn infected plant
Leaf beetle	Legume e.g. cowpea soyabeans	They eat up the leavesReduce photosynthesisReduced yield	Spray with insecticidesUse resistant varieties
Cocoa mirids (capsids)	Beverages e.g. cocoa	They inject toxic saliva into plantTransmit fungal diseasesReduced yieldStunted growth	Spray with insecticide e.g. Gammalin 20Regular weeding
Yam beetles	Tubers e.g. yam	Bore holes into yam tubersReduction in yieldReduction in quality and market value	Dust yam sets with Adrin dust before plantingCrop rotation
Cassava mealybugs	Tubers e.g. cassava	Twisting of stem and reduce internodesSwelling of shootsReduced yield	Early plantingUse resistant varietiesCutting treatmentSpray with insecticides
Green spidermite	Tuber e.g. cassava	They feed on the leavesReduce rate of photo synthesisReduction in yield	Use biological controlSpray with insecticides.
Variegated grasshopper	Tubers e.g. cassava, yam	Adults and larvae eat up the leaves and stemReduce the rate of photosynthesis Reduced growthReduced yield	Hand pickingSpray with insecticides e.g. Adrex 40.
Cotton stainer	Cotton	They pierce and suck sap from plants.Produce toxic salivaTransmit diseases.Reduce quality of bollLeaf distortion	Hand picking Spray with insecticides.
Cotton bollworm	Cotton	Larvae feed on the seeds of cottonCrop rotationDestroy the lint and reduce its qualityPremature fall of cotton boll.	Spray with insecticides to kill insects.Burn cotton plant debris after harvesting.
Thrips	Vegetables e.g. onion, tomato	Browning of leavesWilting of plantReduced yield	Spray with insecticides.
Leaf rollers   Leaf beetle	Vegetable   Vegetables e.g. pepper, okro, tomato	Rolling and twisting of leaves.Reduction in rate of photosynthesis.Reduce yieldThey eat up the leaves and stemsReduced photosynthesisReduction in yield and quality	Spray with insecticides e.g. Vetox 85.   Spray with appropriate insecticides e.g. Vetox 85
Bean beetle, grain weevils	Stored produce e.g. rice, cowpea, maize	Bore holes into grainsand eat them up.Reduce the quality of stored produceReduce quality of grains to powderReduce farmer’s incomeIt reduces the market value of grainsIt reduces viability of infested grains.	Early harvestingProper storage of produce Proper cleaning and fumigation of store with phostoxin tablets or with lindane dustStore grains over fire placesProper drying of seeds to reduce moisture content and kill the eggs and larva of pest.
Birds	Rice, maize, millets, sorghum	Feed on grains in the fieldReduction in quality and yieldReduction in income of farmer	Use of bird scarer or scare cow.Use of cage traps with baitsDrumming or noise making on the farmShooting with catapultUse of explosive mechanism at regular intervalsUse of avicidesFencing/screening farms in greenhouse.
Rodents e.g. bush rabbit, rats, squirrel	Rice, yam, cassava, fruits	They feed on cropsDestroy whole plantsReduction in yieldIncrease in cost of production	Trapping with baitsUse of rodenticidesUse of string/wire tapesUse of predator e.g. dogs and catsClean weeding of farmsShooting and fencingUse of pit traps.
Monkeys	Cocoa, mango, banana, orange.	They eat up the fruitsReduce the quality of fruitsLosses to the farmer	Use traps Shooting with gun where possible

EFFECTS OR ECONOMIC IMPORTANCE OF INSECT PESTS IN CROP PRODUCTION

1. Insects pest destroy crops in the field through their biting, chewing, boring, sucking and defoliation activities
2. They cause reduction in viability of stored produce
3. Spot of injuries by insets may predispose crops to disease attact.
4. They increase the cost of production during the course of controlling them
5. They render vegetables and fruits unattractive and unmarketable
6. Some are carriers or vectors of diseases.
7. The profits of farmers are reduced
8. They reduce the quality of produce either in the store or in the field
9. They generally reduce the yield of crops
10. They can also cause total death of crop plants.

WEEK 10

PREVENTION AND CONTROL OF PESTS.

Pests of crops can be prevented or controlled through the following methods:

(1)  Physical control; (2) Cultural Control  (3) Biological control;  (4) chemical control.

1. Physical Control:  This involves the physical removal of pests by:
2. Handpicking of insects and larvae,
3. Setting traps to catch rodents.
4. Shooting rodents with gun.
5. Fencing round the farm with wire nets.
6. Cultural Control:  This method involves the use of farm practise to prevent or control pest especially on the field. Examples of cultural control include:
7. Practicing crop rotation
8. Use of pest resistant varieties of crops
9. Appropriate tillage operations
10. Use of insect traps
11. Handpicking and destruction of insects,
12. Burning crop residues,
13. Timely planting of crops
14. Proper weeding or sanitation
15. Timely harvesting.
16. Close season practices, especially in cotton
17. Biological Control:  This involves the introduction of the natural enemies of pest to control or the pests population under control. Such enemies eat up or feed on these pests thereby reducing the population of the pest.
18. Chemical Control:  This involves the use of chemical called insecticides or pesticides to control pests or crop plants.

Definition of Insecticides

An insecticide is a chemical preparation used to control insect pest.

Forms of Groups of Insecticides

There are four major forms or groups of insecticides used in the control of insect pests of crops. These forms or groups and their mode of action are:

            Groups                       mode of action

(i)         Powder                        (i)         Contact

(ii)        Liquid                         (ii)        Systemic

(iii)       Granules                      (iii)       Stomach

(iv)       Gas (eous)                   (iv)       Fumigation

These groups of insecticides can be used either directly on insects, seeds, plants and plant parts to check the activities of insects.

Examples of chemicals used to control pests are:

1. Pesticides        –           chemicals to control pests
2. Insecticides     –           chemicals to control insect, e.g. Grasshopper
3. Rodenticides   –           Chemicals to control rodents, e.g. Rats
4. Avicides          –           Chemicals to control birds, e.g. weaver birds
5. Nematicides    –           Chemicals to control nematodes, e.g. Eel worms.

SIDE EFFECTS OF THE VARIOUS PREVENTIVE AND CONTROL METHODS OF DISEASE AND PESTS OF CROPS

The use of various control methods of disease and pests has some side effect.  These side effect are follows:

(a)        Chemical Method of Control

1. Some beneficial insects and soil organisms may be destroyed
2. The chemical used may be toxic to man and domestic animals
3. It may leave undesirable residue in the environment
4. Pests and diseases may develop resistance to chemicals
5. Some are washed out of soil to rivers and streams where they can endanger aquatic life and cause pollution
6. Empty containers could be a source of poisoning when used as container for consumables.

(b)       Biological Methods of Control

1. The new organism introduced may start attacking crops which were originally free from attack
2. The predators expected to control other may rather feed on other beneficial insects
3. The activities of the new organism introduced may cause serious imbalance in the ecosystem.

(c)        Cultural Method of Control:

1. The use of  fire to kill harmful pests may also result in the destruction of other beneficial organism
2. Resistant varieties may become adapted to the environment so that the resistance in short-lived where fire is used.
3. It care is not taken, fire may spread to other farms.
4. The use of fire may cause the destruction and loss of organic matter from the soil
5. It may also lead to the destruction of soil structure and cause soil erosion.