1. Plants Nutrients Challenge!
Complete the grid using the words on the board.
Challenge: What are fertilisers and what are the problems with using fertilisers?

2. Plant and minerals summary
Complete this table of plant mineral needs and deficiencies.
Mineral
Use in plant
Deficiency signs
nitrogen
phosphorus
potassium
magnesium

3. Complete this table of plant mineral needs and deficiencies.
stunted growth and
yellow leaves
making roots
making chlorophyll
yellow leaves with
dead spots
making flowers
and fruits
leaves turn yellow
from the bottom
poor roots and
purple leaves
making leaves

4. Weeds and Pests Lesson Objectives
C/W
Date:……………………
Weeds and Pests
Lesson Objectives
To describe the how weeds impact on plant growth.
To explain the problems of using pesticides.
Success Criteria
List examples of weeds.
Name the advantages and disadvantages of using herbicides and pesticides.
List the problems of pesticides like DDT.

5. Essential Nutrients (mineral salts)
Plant Growth
Plants absorb nutrients from soil
Plants die 1.
Soil
Essential Nutrients (mineral salts)
* Fertile *
Decompose
Nutrients returned to the soil

6. Soil becomes infertile = No Crops
Crop plants are harvested
The plant is removed
Soil quality decrease
Nutrients decline
Soil becomes infertile = No Crops
No Decomposition

7. What are the problems
with plant growth?
Weeds
Pests

8. Name the weeds in the pictures Which plant is not a weed?
What is the man doing?

9. What is a weed?
Is a plant growing where it is not wanted.
E.g. poppies in a field of barley.
Weeds compete with other plants for…?

10. Weeds are a type of plant that compete with crop plants for; Space
What are weeds?
Weeds are a type of plant that compete with crop plants for;
Space
Water
Light
Mineral salts

11. What impact does this cause??
What are weeds?
What impact does this cause??
Fewer resources for crop plants to use for growing
Decrease in yield
Solution???
Herbicides or weedkillers

12. How can we
get rid of weeds?
Herbicides are used by farmers to kill weed plants.
Read through the worksheet ‘Using herbicides’ and answer the questions.

13. The New Farmers Guide to Crop Growth
Process of plant growth and decomposition for;
Wild Field
Farmed Field
Why do we need fertilisers?
What are they?
Types of fertiliser
Problems
Crop Yield
Poster
Leaflet
The New Farmers Guide to Crop Growth
Weeds
What are they?
How do they affect farming?
Solutions:
1. Herbicides or weedkiller.
Pests
What are they?
How do they affect farming?
Affects on food chains
Solutions??
Chemical: Pesticides
Biological Control
Problems to crop growth:
Weeds
Pests

14. What are the problems
with plant growth?
Weeds
Pests

15. What is a
pest?

17. Pests
Pest = An organism that damages or eats crops that humans grow.
Example = ??
Pests limit the number of crop plants in the human food chain.
Pests compete with humans for the crops.

18. What allows
pests to
destroy crops quickly?

19. Solution to Pests Problems??
Pesticides = A chemical that kills pests
Problems??
= Pesticides can affect other organisms in a food web, and may kill useful animals as well as the pests.
Solution??
Specific Pesticides

20. Complete the worksheet questions

21. Insecticides Insecticide Example: DDT
DDT is persistent, where this pesticide does not break down in the environment and passes up food chains.
Pests can kill other organisms as well as pests.
Poisons can be passed through food chains and get more concentrated at each step.

22. Video! What is DDT? Why was it banned in 1972?
What is DDT?
Why was it banned in 1972?
Why is DDT needed to be used in Africa?

23. Negative Negative DDT = Positive DDT = Positive
Saved millions of people from ………….. and starvation.
Been used to control the ………………. that spread malaria.
Helps to reduce the numbers of …………….. that eat food crops.
DDT does not …………. down easily and …………….. in the environment for a long time.
It does not break down inside the body of …………….. either.
DDT passes along the ………………. chains
The pesticide builds up along food chain which is called b…………………...
Negative
Saved millions of people from ………….. and starvation.
Been used to control the ………………. that spread malaria.
Helps to reduce the numbers of …………….. that eat food crops.
DDT does not …………. down easily and …………….. in the environment for a long time.
It does not break down inside the body of …………….. either.
DDT passes along the ………………. chains
The pesticide builds up along food chain which is called b…………………...
Negative
DDT =
Positive
DDT =
Positive

24. Video!
DDT is a very dangerous and effective pesticide that can kill any insect.
Positive:
Saved millions of people from disease and starvation. Been used to control the mosquitoes that spread malaria.
Helps to reduce the numbers of insects that eat food crops.

25. Video!
Negative:
DDT does not break down easily and stays in the environment for a long time.
It does not break down inside the body of animal either.
DDT passes along the food chains
The pesticide builds up along food chain which is called bioaccumulation.

26. Quick Recap!

27. What is a
food chain?

28. Food Chains A food chain shows what is eaten by what.
Food Chains and webs begin with energy from the sun.
The arrows show which way the energy is going in the chain

29. What is a
food web?

30. Food webs Food webs contain many interlinking food chains.
Challenge Question: What food chains can you see?

33. Place the statements in the correct order.
Pesticide Challenge!
Cut the statements up.
Place the statements in the correct order.

34. The New Farmers Guide to Crop Growth
Process of plant growth and decomposition for;
Wild Field
Farmed Field
Why do we need fertilisers?
What are they?
Types of fertiliser
Problems
Crop Yield
The New Farmers Guide to Crop Growth
Weeds
What are they?
How do they affect farming?
Solutions:
1. Herbicides or weedkiller.
Pests
What are they?
How do they affect farming?
Affects on food chains
Solutions??
Chemical: Pesticides
Biological Control
Problems to crop growth:
Weeds
Pests

36. Biological Control

37. Biological Control What is biological control?
Is an alternative natural method to control pests.
It involves using a predator to kill the pest that is eating the plant.
The predator is called a biological control agent.
Example ??
What would the farmer need to consider?

38. Packing Away! 1 2 3 Thank you Stop, Listen and Silence
Pack away your equipment into your bag 3
Stand up, and await dismissal
Thank you

39. True or False?? OR
True
False

40. Two types of fertiliser are natural and artificial.

41. Potassium and Phosphates
Three main mineral
salts in fertilisers
are Nitrates,
Potassium and Phosphates

42. has better quality soil
A farmed field
has better quality soil

43. Weeds compete with
the crop plants for
space, water, light
and mineral salts.

44. What method would you use against pests:
a. Chemicals
b. Biological methods

45. Herbicides kill weed plants

46. Are fertilisers a good
method to increase
crop yield?

47. Biological control is an
alternative method
of controlling pests.