Topic 2 Element 3 - Plant competition

Question 1

Why control weeds?

Answer 1

• they compete with desired plants for light, nutrients and water
• lack of aesphetic appeal
• act as hosts to pests and pathogens

**Capsella bursa-pastoris **
can host and spread Brassica diseases white blister and clubroot as well as host aphids

Question 2

How can weeds be helpful?

Answer 2

• can be used as cover crops
• help recycle nutrients, deep rooted weeds bring nutrients from lower in the soil into foliage
• help to support wildlife and pollinators
• can give you an indication of soil type

Question 3

What is a cover crop?

Answer 3

Cover crops prevent soil erosion, intercept rainwater and sustain year round ecosystem when soil would otherwise be bare.

Question 4

Cultural ways to control pest, diseases and weeds?

Answer 4

• increasing crop/desired plant density
• crop rotation
• mulching to suppress

Question 5

Benefits of cultural control?

Answer 5

• effects usually sustained
• easily incorporated into garden routines

Question 6

Limitations of cultural control?

Answer 6

• can be slow to take effect
• increasing density may cause desired plants to compete

Question 7

Physical ways of controlling pests, diseases and weeds

Answer 7

• hoeing / thermal weeding
• mechanical brushing
• hand removal of weeds
• digging out weeds

Question 8

Benefits of Physical control?

Answer 8

• very targeted
• enables weeds to decompose and feed soil (hoeing)

Question 9

Limitations of Physical control?

Answer 9

• may need repeating
• time consuming
• digging out weeds can release carbon dioxide and destroy mycorrhizal fungi networks

Question 10

What is Chemical control of pests, diseases and weeds?

Answer 10

Application of chemicals to prevent or kill a pest, disease of weed.

Question 11

What does Pesticides refer to?

Answer 11

Refers to herbicides, insecticides, fungicides and other similar substances that prevent or kill pests, diseases and weeds.

Question 12

Benefits of Chemical control?

Answer 12

• is quick to deal with the problem
• can be targeted

Question 13

Limitations of Chemical control?

Answer 13

• Herbicide drift can harm other plants
• can be dangerous to humans, pets desired plants and other wildlife
• Many herbicides have been withdrawn from commercial use as evidence grows that some are carcinogenic
• harmful to earthworms and other soil organisms

Question 14

What is a contact herbicide?

Answer 14

They enter the leaf or stem and kill only the tissue it comes into contact with.

Question 15

What is a translocated herbicide?

Answer 15

They translocate down the plant via the phloem from where they were applied usually the leaves.

Question 16

What is a selective herbicide?

Answer 16

Selective herbicides target only particular weeds. Generally used in lawns to kill eudicotyledonous weeds in grass.

Question 17

What licenses are required to apply pesticides?

Answer 17

• PA1
• PA6

Question 18

What does The Weed Act (1959) require?

Answer 18

This act requires landowners by law to control injurious weds on their property.

Cirsium vulgare
Cirsium arvense
Rumex crispus
Rumex obtusifolius
Senecio jacobaea

Question 19

What is a pernicious weed?

Answer 19

A pernicious weed is a plant that is harmful, invasive and destructive to other plants.

Question 20

What is the latin name for Japanese Knotweed?

Answer 20

Fallopia japonica

Question 21

What act prohibits Fallopia japonica to grow in the wild?

Answer 21

The Wildlife & Countryside Act (1981)

Question 22

What form is requires sellers of a property to detail the presence and location of Fallopia japonica. As well as an eradication plan to be performed by a contractor?

Answer 22

TA6

Question 23

Where must Fallopia japonica be disposed of?

Answer 23

Licenced landfill