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DIFFERENCES BETWEEN MONOGASTRIC AND RUMINANT ANIMAL DIGESTIVE SYSTEM

DIFFERENCES BETWEEN MONOGASTRIC AND RUMINANT ANIMAL DIGESTIVE SYSTEM MONOGASTRIC ANIMAL RUMINANT ANIMALS Possesses only one stomach 1. Po...

IDENTIFICATION OF WEEDS AND GRASSES



Meaning of weeds

Weeds are plants found growing where they are not wanted. They are plants which are not usually cultivated by the farmer foil are found growing among cultivated crops.
definition of a weed.
An herb is a plant that grows in an undesirable area. On grass, we usually organize weeds in two categories: broadleaf weeds and grasses. Broadleaf weeds are easy to identify because they are large and sometimes look like flowers. Dandelions, henbit and clover are all examples of a broadleaf weed. On the other hand, weeds can be a little harder to detect and identify because they look like grass.
Start with the end in mind
Top view of a lawn full of weeds
This lawn is full of weeds.
View of a lawn without weeds
This grass is free of weeds and uniform.








Objectives:
1. Explain the meaning of weeds.
2. Identify common weed types.
3. Explain the harmful effects of weeds on crop plants
4. Enumerate various methods of controlling weeds.

8. Differences between plants and animals
9. Organization of life
10. Complexity of organization in higher organisms
11. Kingdom monera
12. Kingdom Protista

Meaning of weeds

Weeds are plants found growing where they are not wanted. They are plants which are not usually cultivated by the farmer foil are found growing among cultivated crops.

1.

Characteristics of weeds

1. Weeds have very high ability to multiply, They emerge first when optimum conditions ate provided. 2. Weeds produce many seeds. This makes them spread easily.
3. They have devices like spines, hooks, wings which make their dispersal easy.
4. Weeds have high competitive and aggressive growth' habits and easily smother crops if not controlled on time. Examples are guinea grass and elephant grass that can over-run the farm if not regularly weeded.
5. Their seeds are hardy and tough. They can withstand very adverse cond.itions as a result of their tough protective coverings.. Examples are seeds-of legumes.

AGRICULTURAL SCIENCE AND UNDERSTANDING BASIC AGRICULTURE AND FARMING FOR SCHOOLS
Agriculture, farming, agricultural products and crops classification, cultural practices in agricultural science


6. Weeds seeds have long viability period.
7. Weeds are very persistent-and can defy most control measures. They can re-grow from seeds, broken stolons or rhizomes and this supports their persistence.

2.

Effects of Weeds on Crops









1. Weeds compete with crops for water, light, and mineral nutrients. Those with broad leaves over-shadow the crops from direct light intensity and in turn reduces photosynthesis. They utilize nutrients and water in the soil thereby preventing the crops from getting them.
2. Because of their ability to grow fast, weeds can suppress growth of crops on the farm thereby reducing their development and yield.
3. Weeds reduce the quality of farm produce. Weed seed contaminate harvested crops, thereby reducing the quality and market value of such crops. For examples, seeds of wild onion could mix with maize. This can cause an objectionable odour in maize flour. Also seeds of wild rice could mix with harvested rice and reduce the quality in the market.
4. Weeds serve as alternative host to pests and disease organisms that could affect cultivated crops.
5. Some weeds produce toxic substances which are harmful to the crops.
6. Weeds bring about increase in the cost of production. The cost of labour, equipment and chemicals for effective weed control, is an added cost to the cost of crop production.

economic importance of weeds and grasses

Apart from having direct effects on crops, weeds are also important in agriculture for the following reasons:
1. They can cause reduction in the value of land.
2. Some needs are poisonous to both human beings and animals.
3. Weeds reduce the quantity and quality of livestock products. Weeds such as goat weeds get attached to the hair of animals thereby reducing the value of wool or hide.
4. Some weeds are edible by both man and animals.
5. Some weeds have medicinal values.
6. Weeds, when they decay, help to enrich the soil.
7. Some can be used for green manuring.
8. Weeds are used for mulching








Dispersal of weeds

Weeds are mainly dispersed by gutter, animals, explosion and man. the following agents: wind.

1. Wind The structures of some weed seeds enable their distribution by wind. Such features as being winged, having parachute make them easily carried about by wind. Examples of weeds dispersed by wind and Tridax procumbens and Ageratum conyzoides (Goat Weed).

2. Water Weed seeds can be carried by moving water such as surface run-oft, streams, irrigation and drainage water. They have adaptation lentus (hat enable movement by water such as membranous sacs containing air of corky protuberances.
These make the seeds buoyant on water so that they can float. They can also stay in water for a period without losing viability. Example of weed dispersed by water is pig weed.

3.

Animal dispersal of weeds

Animals also help in weed dispersal. For instance, weeds that have hooks can be distributed by animals with hairy body because such weeds can attach themselves to the hair of the animals. Example of weeds dispersed by animals is Erogratis tenella. Also seeds of some weeds pass through the digestive tracts of animals, particularly birds without loosing viability. On defecation, these seeds can germinate into new plants.

4. Man Man can transport weed seeds over long distances as a result of movements of agricultural seeds, foodstuff, nursery stock and others. Some weeds or their seeds could cling to the wears of the farmers and these are deposited elsewhere.

Good examples are
Boerhevia diffusa (Pig weed) and Acathespermum hispidium.

5.

Self Explosion or Explosive Mechanism of weed dispersal

.
This is brought about by the forces set up in dry walls of weeds fruits which cause explosion. This scatters the seeds in the fruits away from the parents plants.
Such weeds are said to be self dispersed. Examples are Sida acuta and Desmodium.

Some common garden weeds

Common names--------Botanical names
1 Guinea grass------Panicumm maximum
2 Elephant grass-------Pennisetum purpureun
3 Tridax------Tridax prociimbem
4 Carpet grass------Axonopus compressus
5 Goose grass or Africana--------Cynodon dactylon
6 Siam weed--------Eluesine indica
7 African or bush marigold-------Chromoleana odorata
8 Pig weed------Aspilia africana
9 Goat weed or blue top------Boerhavia diffusa
10 Water leaf-----Ageratum conyzoides

11 Soft weed-----Talinum triagulare
12 Wild green-------Erogratis tenella
13 Tropical kudzu-------Amaranthus spinosus
14 Centro-------Calapogonium mucunoides
15 Blue flower or water grass-------Centrosema pubescens
16 Spear grass-------Commelina spp
17 Striga-----Imperata cylindrical
18 Wild potato or morning glory------Striga senegalensis
19 Broom weed-----Ipomea spp
20 Emilia------Sida acuta
21 Giant star grass-----Emilia sonchifolia
22 Stubborn grass-------Cynodon nlemfuensis
23 Sensitive plant------Sporobolus pyramidalis
24 Bur weed-------Mimosa pudica
25 Acanthospermum hisidum

DIAGRAM Figure 2.6.1: Some Common Garden Weeds.

Weed control measures

There are several methods used in weed control.
They can classified into: (a) Mechanical or physical method. (b) Cultural method. (c) Biological method. (d) Chemical method. (a) physical me

(i) Hand pulling:
1 this the pulling of weeds by hand in the farm. Though it is efficient, but only useful in small gardens and not large farms.
(ii) Hoeing: The short or small hoe is very useful in weeding. It is used to cut the weed below the crown of the plant which gives, complete destruction of the shoot system.

It is effective in the control of weeds either in pasture, home garden or row crops. Hoe can be used to weed from the furrow to the top of a ridge. Its use is however on a limited and it requires plenty of labour.

(i)

Mowing:

This method helps to prevent seed production in till of weeds.
It removes all unsightly weed growth especially where weeds are too much for effective cultivation to take place. The method can be used to control weeds in lawns, plantation or fields. The mower is normally attached to a tractor or pulled by hand to move over the area to be cleared.

(ii)

Flooding:

This is done by keeping the area to be weeded Hooded up to 20 cm of water for 3 to 8 weeks. This practice kill, the weeds because they can no longer receive air for respiration.

(iii)

Heat treatment:

Heal can be used in controlling weeds. For instance nursery soil is sterilised to kill all weed parts and seeds. Fire ran be used to burn dry weeds on cultivated land before cultivation starts.

(iv)

Smothering with non-Living materials:

Weeds can be Followed by the use of mulch materials such, as papers, hulls from rice, manure, plastic materials or cellophane. These materials help to exclude sunlight and prevent shoot growth. The weeds then become etiolated (lose chlorophyll) and die off.








(v)

Cultural method:

This involves the use of cultural practices of crop production to reduce the growth of weeds on the farm. Such cultural practices include i. Burning of farmland: This kills weed parts, seeds and fruits both in the soil and on the surface. ii. Tillage: Tillage helps to expose weed parts for destruction by sun or herbicides. They can also be hand picked and destroyed.

iii. Early planting: This ensures that crops are well established before the weeds start growing.
iv. Good spacing: Proper spacing of crops helps in the reduction of weeds along the crop rows. It also makes it easy for weeding to he done.

mixed cropping:

Planting or two or more crops, together oil the same farmland can help to reduce the intensity of weeds on the farm

(c)

Biological method

This involves the use of living plants and animals to control weeds. They include: (i) Use of suppressive plants: Crops that grow fast and large too can be used to overshadow weeds thereby reducing their growth, Also, cover crops such as melon and legumes like groundnut can be used to control weeds on the farm. (ii) Use of insects: This involves the use of identified insect pests weeds in controlling weeds on the farm. Insects which have been found to feed on a particular weed can be multiplied and introduced to the area to feed and destroy such weed species. (iii) Pasturing: This involves the grazing of farm animals on weeds usually in plantations such as rubber and oil palm. Animals like i cattle, sheep or goat are commonly used in this method.

(d)

Chemical method

This is the method that is used on a large scale. It makes use of chemicals in the control of weeds. These chemicals are known as herbicides. They are sprayed either on the leaves of weeds or applied to the soil. They are classified into:

(i)

Selective herbicides:

These are chemicals that can kill certain groups or species of plants. Example is 2, 4 -D (Dichlorophen-oxyacetic acid). They can be used in cereals, sugar cane and soya-beans farms to reduce weeds.
(ii) Non-selective herbicides: These are the herbicides that can kill any plant which they come in contact with.



Examples are petroleum oils and carbon sulphide. Herbicides can also be classified as contact herbicides, systemic or trans-located herbicides. The contact herbicides are applied as foliage sprays (that is on the leaves), dust or granules: They scotch the tissues of the plants already growing on the farm. Examples are sodium chlorate and arsertates.

The systemic or in trans-located herbicides are carried in the tissues of the plants after the ingredients have been absorbed by the roots in the soil. These chemicals must first enter the soil and then absorbed the roots of the weeds into their tissues. They are applied as dust or granules onto the plants or used as soil treatments. When used as soil treatments, they control all weeds that are to emerge from the soil, hence, they are sometimes called pre-emergence herbicides. Examples are 2,4,5-T(2,4,5-Trichlorophen-oxyyacetic acid), Atrazine and others. Quality of good herbicide A good herbicide recommended for use should have the flowing qualities:
1. It should be able to kill the weeds easily and at a small dosage rate. That is, it should be phytotoxic.
2. It should kill the weeds and not the growing crops. That is, it should be selective in its action.
3. It should have low toxicity on animals that use weeds as food and on man.
4. It should be easy to compound or formulate.
5. It should be easy to use.
6. It should be cheap and easy to get.

PRECAUTIONS TO BE TAKEN WHEN USING HERBICIDES IN HANDLING WEEDS

In handling of herbicides, the following precautionary measures should be observed:
1. It should not be allowed to touch the body either during mixing or use. Therefore, a stick should be used to stir when mixing it with water in a bucket.
2. It should be kept away from food and sleeping rooms. The container containing the herbicide should be marked "danger". It should not be drank,
3. Do not eat or drink when using herbicides.
4. Always put on protective coverings such as hand gloves, overall and rubber boots before using herbicides.
5. Always ensure that you back the wind direction when spraying to avoid spraying onto yourself.
6. Do not spray herbicides on cultivated crops except weeds.
7. Wash your body with soap as well as all spraying equipment after use.

8. Contact a medical doctor when feeling uneasy due to the use of herbicides. Modern, research in weed science has recommended the integrated weed control method for effective eradication of weeds. This method simply means the combination of two or more methods together in the control of, weeds. For instance, cultural practices) such as burning and tillage can be supplemented with pre-emergence herbicides application. That is. spraying the farmland when the weeds have not appeared.

Benefits of weed control




1. Overcrowding and shading of crops are removed.
2. The alternate host of pests and disease organisms of crops are: eliminated.
3. The crops will be able to make full use of nutrients, water, air and light. 4. Water loss from the soil through evaporate-transpiration is brought low.
5. The farm will become clean for easy activities such as application of fertilizer and harvesting operations.
6. There is high yield from crops when weeds are controlled.
7. Weed control reduces contamination of crop products such all rice and vegetables.

2.

MULCHING

This is the covering of soil top most surface with any material aimed at improving the soil nutrients. This involves the covering of the surface soil with any material to prevent loss of water or keep down weeds. Materials such as Sawdust, manure, straw, leaves, paper, sticks, and various other materials are used. It is an effective way of checking evaporation and loss of water from the soil or home. It helps to keep down weeds, thereby reducing transpiration from their leaves.

When organic mulches decay, they add to the nutrients of the soil which increases production and yield. The decayed materials increases the water-holding capacity of the soil. Mulching is also an effective way of utilizing waste products from crop production, like stubble mulch. Mulching reduces surface run-off and increases water infiltration and percolation, which is to say it helps to prevent sheet and gully erosion. It also reduces the effect of temperature on crops. The effect of mulch on the soil and crops cannot be over emphasized. I remember asking my dad in the year 1990 in a town called Amai in Delta State of Nigeria, what he was doing covering the yam heaps with leaves and broken little sticks? Although it was a normal practice to the local farmers but as I grew up began study agricultural science, I got to understand the importance of mulching. So generally mulch forms a layer between the atmosphere and the soil, thereby prevent the direct sunlight from reaching the soil surface. From my survey and study of mulch, it is widely practiced in two forms, they are

1. Organic and 2. Inorganic The type of mulch applied at various times of the season varies. In the wet season the use of plastic or dry sticks are widely used to prevent direct sunlight while fresh grasses, organic materials such as harvested remains of crops are used in dry seasons. The wet season’s mulch is not to prevent transpiration but to shield erosion majorly while the dry season mulching is to prevent transpiration and direct sunlight. The use of plastic mulching is used in large scale farming and applied using tractors to spread it out. The choice of materials for mulching can depend on a lot of factors, like time, location, cost, availability and cultural practices. Here are a list of the types of mulching system 1. Wood mulch 2. Leaves mulch 3. Grass application 4. Tree bark application 5. Use of straw 6. Use of synthetic carpet 7. Organic colored method 8. Anaerobic or sour method 9. Cover crop planting system The list cannot be exhausted in any way and the use of mulch in agricultural and crop production is so enormous that it is advisable to produce most of the mulching materials needed by the farmer himself within reach STUDY QUESTIONS 1. What are weeds? Give Ten examples of common garden weeds 2. State Five harmful effects of weeds on cultivated crops. 3. List four major ways through which weeds can spread. 4. List Ten common weeds. State their common and botanical 5. Enumerate four ways through which weeds can be controlled on your school farmland. 6. Briefly explain the following as methods of weed control (i) Hoeing (ii) Use oj insects (iii) Selective herbicides (iv) Early planting (v) Integrated weed control. 7. Enumerate Five precautions you would take when using chemical herbicides in weed control. 8. What are the benefits of weed control to the farmer and his crops? 9. State four qualities of a good herbicide. 10. Briefly explain integrated weed control method and why would you recommend it?

WEEDS

Weeds are vegetation located growing in which they may be not wanted. they are flora which are not typically cultivated by the farmer foil are discovered growing among cultivated crops.

1.

characteristics of weeds


1. Weeds have very excessive potential to multiply, They emerge first whilst most advantageous situations ate provided.

2. Weeds produce many seeds. This makes them spread without problems.

3. they have got gadgets like spines, hooks, wings which make their dispersal clean.

4. Weeds have high competitive and competitive growth' behavior and without problems smother vegetation if now not controlled on time.

Examples are guinea grass and elephant grass which could over-run the farm if no longer frequently weeded.

5. Their seeds are hardy and hard. they could face up to very damaging conditions as a result of their hard defensive coverings.. Examples are seeds-of legumes.

6. Weeds seeds have long viability length.

7. Weeds are very continual-and can defy most manage measures. they could re-grow from seeds, broken stolons or rhizomes and this supports their persistence.

2.

Effects of Weeds on crops


1. Weeds compete with plants for water, mild, and mineral vitamins. people with large leaves over-shadow the vegetation from direct light intensity and in turn reduces photosynthesis. They make use of nutrients and water within the soil thereby preventing the crops from getting them.


2. due to their capability to develop rapid, weeds can suppress increase of crops on the farm thereby lowering their development and yield.

3. Weeds lessen the first-class of farm produce.







Weed seed contaminate harvested crops, thereby reducing the exceptional and marketplace cost of such vegetation. For examples, seeds of wild onion may want to blend with maize. this could purpose an objectionable odour in maize flour. also seeds of wild rice could blend with harvested rice and reduce the fine inside the market. four.

4. Weeds function alternative host to pests and ailment organisms that might affect cultivated vegetation.

5. a few weeds produce poisonous substances which might be harmful to the plants.

6. Weeds result in boom within the fee of production.



The value of labour, device and chemicals for powerful weed control, is an brought value to the fee of crop manufacturing. apart from having direct effects on vegetation, weeds also are important in agriculture for the following motives:



1. they could cause reduction in the value of land.

2. a few wishes are poisonous to both humans and animals.

3. Weeds lessen the amount and satisfactory of livestock products. Weeds which includes goat weeds get connected to the hair of animals thereby reducing the value of wool or conceal.

4. a few weeds are fit to be eaten with the aid of both man and animals.

5. some weeds have medicinal values.

6. Weeds, after they decay, assist to complement the soil.

7. a few may be used for green manuring. eight.

Weeds are used for mulching

Dispersal of weeds


Weeds are in particular dispersed by means of gutter, animals, explosion and guy. the following marketers: wind.

1. Wind The structures of a few weed seeds enable their distribution by means of wind. Such functions as being winged, having parachute cause them to easily carried about by means of wind. Examples of weeds dispersed by way of wind and Tridax procumbens and Ageratum conyzoides (Goat Weed).

2. Water Weed seeds may be carried through moving water which includes surface run-oft, streams, irrigation and drainage water. they have got adaptation lentus (hat permit motion via water including membranous sacs containing air of corky protuberances. these make the seeds buoyant on water so as to go with the flow.

They can also live in water for a period with out losing viability. instance of weed dispersed by using water is pig weed. three.

Animals Animals additionally help in weed dispersal. as an example, weeds that have hooks can be distributed by using animals with hairy body because such weeds can attach themselves to the hair of the animals.

instance of weeds dispersed via animals is Erogratis tenella.

additionally seeds of a few weeds bypass via the digestive tracts of animals, mainly birds without loosing viability.

On defecation, those seeds can germinate into new flowers. four. guy guy can transport weed seeds over lengthy distances due to movements of agricultural seeds, foodstuff, nursery stock and others. some weeds or their seeds should hold to the wears of the farmers and these are deposited elsewhere.

proper examples are

Boerhevia diffusa (Pig weed) and Acathespermum hispidium.

5. Self Explosion or Explosive Mechanism

this is delivered about via the forces set up in dry partitions of weeds end result which cause explosion. This scatters the seeds inside the end result away from the dad and mom plant life. Such weeds are said to be self dispersed.

Examples are Sida acuta and Desmodium.

some common place lawn weeds common place names Botanical names

1 Guinea grass Panicumm maximum

2 Elephant grass Pennisetum purpureun three Tridax Tridax prociimbem four Carpet grass Axonopus compressus 5 Goose grass or Africana Cynodon dactylon 6 Siam weed Eluesine indica 7 African or bush marigold Chromoleana odorata eight Pig weed Aspilia Africana 9 Goat weed or blue top Boerhavia diffusa 10 Water leaf Ageratum conyzoides eleven gentle weed Talinum triagulare 12 Wild green Erogratis tenella thirteen Tropical kudzu Amaranthus spinosus 14 Centro Calapogonium mucunoides 15 Blue flower or water grass Centrosema pubescens 16 Spear grass Commelina spp 17 Striga Imperata cylindrical 18 Wild potato or moring glory Striga senegalensis 19 Broom weed Ipomea spp 20 Emilia Sida acuta 21 massive star grass Emilia sonchifolia 22 cussed grass Cynodon nlemfuensis 23 touchy plant Sporobolus pyramidalis 24 Bur weed Mimosa pudica 25 Acanthospermum hisidum DIAGRAM determine 2.6.1: a few commonplace garden Weeds.

6.4

Weed control measures


There are numerous techniques used in weed manipulate. they can categorised into: (a) Mechanical or physical approach. (b) Cultural technique. (c) biological technique. (d) Chemical approach. (a) Mechanical or physical approach

(i) Hand pulling:

1 this is the pulling of weeds with the aid of hand within the farm. though it's miles efficient, but best useful in small gardens and now not large farms.

(ii) Hoeing: the fast or small hoe is very useful in weeding. it's miles used to reduce the weed under the crown of the plant which gives, complete destruction of the shoot gadget. it's far effective within the manage of weeds both in pasture, domestic lawn or row vegetation. Hoe can be used to weed from the furrow to the top of a ridge. Its use is however on a constrained and it calls for masses of labour.

(iii) Mowing: This technique helps to prevent seed manufacturing in until of weeds. It eliminates all unpleasant weed boom specifically where weeds are too much for powerful cultivation to take region. The method may be used to govern weeds in lawns, plantation or fields. The mower is typically attached to a tractor or pulled by hand to move over the place to be cleared.



(iv) Flooding: this is executed with the aid of retaining the region to be weeded Hooded up to 20 cm of water for three to eight weeks. This practice kill, the weeds due to the fact they can not get hold of air for transpiration. (v) warmness treatment: Heal may be used in controlling weeds. for example nursery soil is sterilized to kill all weed elements and seeds. fireplace ran be used to burn dry weeds on cultivated land before cultivation starts off.

(vi) Smothering with non-dwelling materials:

Weeds can be by the usage of mulch materials such, as peppers, hulls from rice, manure, plastic substances or cellophane. those materials help to exclude daylight and save you shoot burm. The weeds then end up isolated (lose chlorophyll) and die off.

(vii) Cultural method:

This involves the usage of cultural practices of crop production to lessen the growth of weeds on the farm. Such cultural practices consist of
Burning of farmland:

This kills weed parts, seeds and culmination each within the soil and at the surface.

ii. Tillage: Tillage enables to reveal weed elements for destruction via solar or herbicides. They also can be hand picked and destroyed.
iii. Early planting: This ensures that crops are nicely hooked up earlier than the weeds begin growing. iv. top spacing: right spacing of crops facilitates within the discount of weeds along the crop rows. It also makes it easy for weeding to he executed.

v. mixed cropping: Planting or two or more plants, collectively oil the equal farmland can help to reduce the depth of weeds at the farm

(c) biological technique This entails using living plant life and animals to manipulate weeds. They encompass:

(i)

Use of suppressive vegetation:


vegetation that grow speedy and large too can be used to overshadow weeds thereby lowering their boom, also, cowl vegetation inclusive of melon and legumes like groundnut may be used to govern weeds on the farm.

(ii) Use of bugs: This involves using recognized insect pests weeds in controlling weeds at the farm. insects that have been observed to feed on a particular weed may be elevated and introduced to the location to feed and wreck such weed species.

(iii) Pasturing: This includes the grazing of livestock on weeds typically in plantations together with rubber and oil palm. Animals like i livestock, sheep or goat are generally used in this technique.

(d) Chemical technique that is the method this is used on a huge scale. It uses chemical compounds in the manipulate of weeds. those chemicals are called herbicides. they're sprayed both on the leaves of weeds or implemented to the soil. they are categorised into:


(i) Selective herbicides: those are chemical compounds that can kill certain organizations or species of flora. example is 2, 4 -D (Dichlorophen-oxyacetic acid).

They can be utilized in cereals, sugar cane and soya beans farms to lessen weeds.

(ii) Non-selective herbicides: these are the herbicides which can kill any plant which they arrive in touch with. Examples are chemical chlorates, petroleum oils and carbon disulphide.

Herbicides also can be categorized as touch herbicides, systemic or trans-located herbicides. The contact herbicides are carried out as foliage sprays (this is on the leaves), dirt or granules:

They scotch the tissues of the flora already developing on the farm. Examples are sodium chlorate and arsertates.

The systemic or in trans-located herbicides are carried within the tissues of the flora after the substances had been absorbed via the roots in the soil. these chemicals have to first enter the soil and then absorbed the roots of the weeds into their tissues. they are carried out as dust or granules onto the flora or used as soil remedies.

when used as soil treatments, they manipulate all weeds that are ilt to emerge from the soil, for this reason, they are from time to time called pre-lltrgencc herbicides. Examples are 2,four,five-T(2,4,five-Trichlorophen-oxyyacetic acid), Atrazine and others. quality of properly herbicide a very good herbicide recommended for use must have the flowing characteristics:

1. It should be capable of killing the weeds without problems and at a small dosage charge. this is, it must be phytotoxic.

2. It need to kill the weeds and now not the growing plants. that is, it have to be selective in its motion.

3. It should have low toxicity on animals that use weeds as food and on man.

4. It should be easy to compound or formulate.

5. It should be easy to use.

6. It must be cheap and easy to get.

PRECAUTIONS TO BE TAKEN when using HERBICIDES
In coping with of herbicides, the subsequent precautionary measures need to be located: 1. It should now not be allowed to the touch the body either at some stage in mixing or use. consequently, a stick must be used to stir when mixing it with water in a bucket. 2. It should be saved faraway from meals and drowsing rooms. The box containing the herbicide shpuld be marked "chance". It ought to now not be drank, 3. Do not devour or drink while usjing herbicides. 4. constantly put on protective coverings together with hand gloves, standard and rubber boots earlier than using herbicides. 5. constantly make certain that you returned the wind route when spraying to avoid spraying onto your self. 6. Do not spray herbicides on cultivated plants besides weeds. 7. Wash your body with cleaning soap as well as all spraying gadget after use. 8. touch a medical health practitioner whilst feeling uneasy because of using herbicides. cutting-edge, research in weed technology has recommended thej incorporated weed manipulate approach for effective eradication of weeds. This metftod honestly means the combination of two or more methods together within the manage of, weeds. for example, cultural practices) along with burning and tillage may be supplemented with pre-emergence herbicides application. that is. spraying the farmland when the weeds have no longer regarded. benefits of weed manage 1. Overcrowding and shading of crops are removed. 2. The change host of pests and disease organisms of crops are: eliminated. 3. The crops will be able to make complete use of vitamins, water, air and light. four. Water loss from the soil thru transpiration is brought low. five. The farm will end up smooth for clean sports such as utility of fertilizer and harvesting operations. 6. there's high yield from plants while weeds are managed. 7. Weed manipulate reduces infection of crop merchandise such all rice and greens. in case you discover our web site beneficial please assist us proportion to complement others also

HERE YOU WILL FIND EVERY AVAILABLE TOPICS ABOUT AGRICULTURAL SCIENCE AND BIOLOGY. AND THE LINKS TO THEIR VARIOUS SOURCES.


1. DEVELOPMENT OF AGRICULTURE
2. IMPORTANCE OF AGRICULTURE
3. SUBSISTENCE AGRICULTURE
4. COMMERCIAL AGRICULTURE
5. PROBLEM OF AGRICULTURAL DEVELOPMENT
6. SOLUTIONS TO POOR AGRICULTURAL DEVELOPMENT
7. AGRICULTURAL LAWS AND REFORMS
8. ROLES OF GOVERNMENT IN AGRICULTURAL DEVELOPMENT
9. AGRICULTURAL POLICIES
10. PROGRAM PLANNING IN AGRICULTURE
11. AGRICULTURAL REGULATIONS
12. AGRICULTURAL EDUCATION
13. RESEARCH INSTITUTES IN AGRICULTURE
14. AGRICULTURAL EXTENSION
15. AGRICULTURAL CREDITS
16. AGRICULTURAL SUBSIDIES
17. QUARANTINE SERVICES
18. VACCINES IN AGRICULTURE
19. FARM SETTLEMENT SCHEME
20. PROBLEMS OF FARM SETTLEMENT SCHEME
21. OPERATION FEED THE NATION








34. FORESTRY
35. WILDLIFE CONSERVATION
36. FACTORS AFFECTING LAND AVAILABILITY
37. TOPOGRAPHY
38. SOIL
39. BIOLOGICAL FACTORS
40. SOCIAL-ECONOMIC FACTORS
41. ENVIRONMENTAL FACTORS AFFECTING AGRICULTURAL PRODUCTION
42. CLIMATIC FACTORS AFFECTING AGRICULTURAL PRODUCTION
43. TEMPERATURE
44. RAINFALL
45. WIND
46. SUNLIGHT
47. SOLAR RADIATION
48. BIOTIC FACTOR AND AGRICULTURAL PRODUCTION
49. PESTS
50. BIRDS
51. DISEASES
52. SOIL MICRO-ORGANISMS
53. SOIL PH
54. ROCK FORMATION
55. IGNEOUS ROCK
56. SEDIMENTARY ROCKS
57. METAMORPHIC
58. SOIL AND ITS FORMATION
59. FACTORS OF SOIL FORMATION
60. LIVING ORGANISM
61. PARENT MATERIALS
62. SOIL FORMATION TOPOGRAPHY
63. PROCESS OF SOIL FORMATION
64. WEATHERING
65. PHYSICAL WEATHERING
66. CHEMICAL WEATHERING
67. PRESSURE
68. WATER




69. WIND
70. HYDROLYSIS
71. HYDRATION
72. CARBONATION
73. BIOLOGICAL WEATHERING
74. CHEMICAL AND BIOLOGICAL COMPOSITION OF THE SOIL
75. SOIL WATER
76. MICRO AND MACRO NUTRIENTS
77. SOIL MICRO ORGANISM
78. PROPERTIES OF SOIL
79. SOIL STRUCTURE
80. SANDY SOIL
81. CLAY SOIL
82. LOAMY SOIL

83. SOIL TEXTURE
84. IDENTIFICATION OF SOIL TYPES THROUGH EXPERIMENTS
85. RETENTION OF WATER BY VARIOUS SOIL TYPES
86. DETERMINATION OF SOIL PH REACTION
87. COLORIMETRIC DETERMINATION OF SOIL PH LEVEL
88. PH SOIL TEST
89. PLANT NUTRIENTS

112.
THE MAINTENANCE OF SOIL FERTILITY
113. CROP ROTATION
114. APPLICATION OF ORGANIC MANURES
115. FARM YARD MANURE
116. APPLICATION OF INORGANIC MANURE

117. LIMING
118. FARMING PRACTICES
119. BUSH BURNING
120. CLEARING

121. FERTILIZER APPLICATION
122. ORGANIC MANURING
123. FARM YARD MANURE

124. HUMUS






133. FARM POWER AND MACHINERY
134. SOURCES OF FARM POWER
135. HUMAN SOURCE
136. ANIMAL SOURCE
137. MECHANICAL SOURCE
138. WIND POWER SOURCE
139. SOLAR POWER SOURCE
140. ELECTRICITY POWER SOURCE
141. FARM MACHINERY

142. FIELD MACHINES
143. TRAILED IMPLEMENTS
144. MOUNTED IMPLEMENTS
145. SEMI MOUNTED IMPLEMENT
146. SELF-PROPELLED IMPLEMENT
147. TRACTORS
148. THE BULLDOZER

149. PLOUGHS
150. THE MOULDBOARD PLOUGHS
151. THE SHARES
152. THE MOULDBOARD
153. THE LANDSLIDE
154. DISC PLOUGH
155. HARROW
156. RIDGERS

157. PLANTERS
158. PRAYERS
159. HARVESTERS
160. HAY HARVESTER EQUIPMENT
161. GRAIN HARVESTING EQUIPMENT
162. INCUBATORS
163. MILKING MACHINE

164. SIMPLE FARM TOOLS
165. AGRICULTURAL MECHANIZATION
166. THE CONCEPT OF MECHANIZATION