R2102 1.5 Describe how the root environment can be improved and protected

Question 1

What is cultivation of soil?

Answer 1

Preparing it for planting or sowing by digging or rotovating

Question 2

Tasks to do before cultivation (4)

Answer 2

1. Clear any unwanted vegetation e.g. weeds
2. Remove any debries e.g. old builders rubble in the soil
3. Ensure adequate depth of topsoil - if shallow extra may need to be added
4. Levelling - any changes of level must be done to the subsoil so strip the topsoil and replace it once levelling is complete

Question 3

When to dig (3)

Answer 3

1. Only when soil conditions are suitable - never when ground is excessively wet, parched or frozen
2. Clay soils best dug in autumn to use weathering effects of frost
3. Light soils (sandy) can be dug in autumn or spring

Question 4

Advantages of cultivation (7)

Answer 4

1. Prepares uncultivated area for planting
2. Improves soil structure by allowing movement of air and water
3. Exposes soil to weathering effects of the weather. Still one of the best ways to improve the structure of heavy soil
4. Breaks up pans at soil surface and below
5. Allows for incorporation of organic matter at different levels in the soil
6. Buries crop remains and weeds
7. Exposes soil pest to weather and predators

Question 5

Disadvantages of cultivation (6)

Answer 5

1. Disturbs the natural structure of the soil built up by earthworm activity
2. Can damage the structure of the soil if carried out at the wrong time or when using heavy machinery
3. Dominant weed seeds are brought to the surface where they will germinate
4. Leaving surface bare can lead to erosion and/or leeching of nurtrients
5. Moisture and warmth may be lost from the soil
6. Hard work!

Question 6

What is Single digging? (5)

Answer 6

1. Digging to the depth of 30cms (a single spit)
2. Avoid bringing subsoil to surface
3. In shallow soils may need to dig less than one spit
4. Used predominatly in vegetable patches, uniformed beds and allotments
5. Add organic matter if needed - particularly in shallow soil

Question 7

What is double digging? (4)

Answer 7

1. Digging to a depth of two spits.
2. Upper spit of the first row is dug out and removed and the spit below dug in situ
3. Organic Matter can be added to the lower spit
4. The upper spit of the second row is then dug and turned over into the lower spit of the first row

Question 8

When to double dig (3)

Answer 8

1. The ground has not been cultivated before or for a long time
2. There are soil pans within the soil profile
3. The soil structure is very heavy

Question 9

What is rotary cultivation? (5)

Answer 9

1. Mechnical assstance for a larger area
2. Rotovator blades penetrate the soil to about 25cm and create a good tilth
   But
3. Using when wet can increase compaction
4. Action of the rotovator can smear any clay fraction in the soil and create a cultivation pan and impede drainage
5. If there are perennial weeds (e.g. Elymus repens - couch grass) the chopping action of the rotovator will spread fragments of roots through the whole cultivated area and increase the weed problem

Question 10

What is forking?

Answer 10

1. Use of a fork to weed, loosen and break up soil
2. Used in modified double digging
3. Fork can be pushed into turf to improve areation and the infiltration of water

Question 11

What is raking?

Answer 11

1. Used to break up soil clods, and remove stones to produce a suitable tilth
2. Used in two main ways
   * Reducing soil aggregates to the size of crumbs. Rake should be pushed and pulled.
   * As a means of removing stones and unwanted vegetation the rake is used like a sieve. The rake needs to be pulled through the seedbed at a 45 degree angle and in one direction leaving the soil crumbs behind
3. Plank should be used to avoid compaction of the soil

Question 11

What is raking?

Answer 11

1. Used to break up soil clods, and remove stones to produce a suitable tilth
2. Used in two main ways
   * Reducing soil aggregates to the size of crumbs. Rake should be pushed and pulled.
   * As a means of removing stones and unwanted vegetation the rake is used like a sieve. The rake needs to be pulled through the seedbed at a 45 degree angle and in one direction leaving the soil crumbs behind
3. Plank should be used to avoid compaction of the soil

Question 12

Soil problems with traditional bed systems

Answer 12

1. Set out in rows on flat ground
2. Working between the rows - planting, weeding, thinning out - all compact the soil. This reduces air in the soil and makes less air available to the crops next to the compacted soil area, reducing growth

Question 13

Advantages of raised bed system (7)

Answer 13

1. Dividing the growing area into narrow beds means that all cutivations are carried out from pathways and the soil in the beds is less compacted
2. Plant spacing can be reduced because there is no need to walk through the rows. Beds should generally be no more than 1.2m across
3. Crops can be picked over, weeded etc even when whether had been wet because there is no need to stand on the soil
4. Organic matter only has to be spread over certain growing areas
5. Soil can be built up to give raised beds with better drainage
6. Raised bed and be made high enough for easier wheelchair access
7. Rasied beds can be made of walling blocks, wood or recycled plastic.

Question 14

Problems with traditional preparation of seedbed (4)

Answer 14

1. Demanding on time, energy and labour
2. Interferes with the natural structure forming agents such as earthworms
3. Done at the wrong time can damage the soil structure, create pans, and make soil vulnerable to erosion
4. Reduces organic matter at the top of the profile where it is most useful

Solution > No dig method

Question 15

No dig method (deep bed system) (5)

Answer 15

1. Double dig the soil and make sure plenty of organic matter is added to boost humus levels and improve soil structure
2. Lay out plot so that all tasks can be done from permenant paths
3. Use raised beds to deepen shallow soils and improve drainage
4. Keep the gound covered to prevent damage to structure by rain
5. Smother weeds out by:
   * Planting closely
   * Intercropping
   * Using green manures
   * Mulching

Question 16

Crop rotation

Answer 16

brassica group/root group/legume and vegetable group

Question 17

What is a soil conditioner (ameliorant)

Answer 17

Added to soil to correct deficiencies in structure and/or nutrients

Question 18

How does soil conditioner help? (5)

Answer 18

1. Improve soil structure (lime)
2. Improve drainage (sand,grit)
3. Improve water retention (compost, green waste, manures, rotting bark, peat)
4. Alter soil ph (lime raises, suplhur lowers)
5. Add nutrients (fertilisers, manures, compost)

Question 19

Manure and compost as soil conditioner (3)
What does it do in the soil?

Answer 19

1. Help soil form good crumb structure
2. When fresh opens up soil to improve aeration and drainage
3. Humus is created which helps crumb formation in very sandy soils and in heavy clays

Question 20

Lime as a soil conditioner (2)

Answer 20

1. Remedy for soil acidity
2. Also contributes calcium which helps clay form crumbs

Question 21

Gypsum as a soil conditioner

Answer 21

Added to soil when clay needs to be improved without raising PH

Question 22

Compaction v consolidation

Answer 22

Consolidate - natural settling due to gravity
Compaction - External forces applied to the soil e.g. animal, human , machnical

Question 23

Compaction (4)

Problems of and remedy

Answer 23

1. Air and water cannot flow through
2. Soil and root development effected
3. Often double digging the only rememdy
4. On agricultural land deep ploughing is done

Question 24

Soil pan issues

Answer 24

1. An impermeable layer below the surface of the soil. 2. Plants will be shallow rooting. If the soil dries out their roots will not be able to penetrate the subsoil to the water held there 3. On heavy soils water may not drain freely so it accumulates above the pan and the top layer of soil can become waterlogged 4. Can happen natually or by cultivation

Question 24

Soil pans (4)

Answer 24

1. An impermeable layer below the surface of the soil. 2. Plants will be shallow rooting. If the soil dries out their roots will not be able to penetrate the subsoil to the water held there 3. On heavy soils water may not drain freely so it accumulates above the pan and the top layer of soil can become waterlogged 4. Can happen natually or by cultivation

Question 25

What is a plough pan?

Answer 25

Compactation at the base of the ploughed layer of soil. Can happen with a rotovator, particularly on a clay soil

Question 26

What is subsoiling?

Answer 26

A tractor drags a winged tine or series of tines behind it through the soil creating cracks and fissures at a much deeper level than normal plough depth to allow drainage and break up the soil pan

Question 27

What is soil capping? (3) | 'after capping'

Answer 27

1. When rain hits the surface over the winter and washes all the finer particles into a surface slurry which dries into a hard cap 2. The same effect can occur ina seed tray when watered from above 3. A similar effect can occur in seed trays when peat free, fibrous composts knit together to form a cap that the seedlings have to break through

Question 28

Prevent soil capping

Answer 28

1. Avoid digging too much in winter, unless you have heavy clay soil 2. Mulch the surface with organic matter 3. Use a green manure to cover the soil. When chopped up in spring the nutrients will enrich the topsoil 4. Avoid using weeds as green manure - ephemeral weeds will persist

Question 29

Effects of improved drainage(6) or how is soil when it is no longer waterlogged

Answer 29

1. Soil structure improved 2. Soil warms up more quickly 3. Movement of carbon dioxide and oxygen is improved 4. In encourages favourable bacteria 5. The rate of organic matter breakdown is accelerated 6. More nutirents are available

Question 30

Indicators of poor drainage (7)

Answer 30

1. Poor plant growth, yellowing of leaves. Defoliation can occur and roots may be black and slimy 2. Standing water on the soils surface - puddling, ponding 3. Soil is consistently wet or may be run off down slopes 4. Certain types of plant might be present e.g. mosses, liverworts, sedges, on soil surface 5. Soil may be black / blue in colour and smell sulphurous when dug 6. Weed problems 7. Winter flooding of crops, grassland and vines

Question 31

Plant indicators of poor drainage (4)

Answer 31

1. Creeping buttercup 2. Tussock grass 3. Moss in turf 4. Sedge growing in moss

Question 32

Main causes of excess water (4)

Answer 32

1. Compaction (impeded drainage) 2. Run-off from hard surfaces 3. Higher ground draining down 4. High water table

Question 33

How to deal with excess water (5)

Answer 33

1. Soakaway (soakaway crate) - Clinker and bricks within 20 cm of surface. Then sand and finally topsoil. Usually 90cms deep and 60cmx90cm square 2. Swales - Shallow ditches with vegetation in them. Slow run-off speeds and allow water to soak away over their length. 3. French drain - conduct water away from a wet area - into drain or soakaway. Often along the edge of patios. Base is impermeable. Can act as reservoir with the water being used to irrigate trees nearby. 4. Adapt - plant a bog garden 5. Build raised beds

Question 34

Methods of irrigation (5)

Answer 34

1. Watering cans - use fine roses and tilt upwards when water seeds / cuttings 2. Hoses fitted with trigger lances - can adjust the flow rate and fineness of spray 3. Sprinklers - delivers water to a large area. Beware of creating standing water that could create a soil cap, Large droplets could damage soil crumbs, Creates a humid atmosphere 4. Trickle lines or seep hoses -delivers water very slowly to soil. However very little sideways spread of water. Creates a drier atmosphere and reduced water loss. 5. Drip irrigation - variation of trickle lines. Minimises water loss because there is no water in the air.

Question 35

Conservation of water

Answer 35

1. Plant selection - draught resistance 2. Use recycled water 3. Minimise evaporation of water 4. Increase water reservoir of soil 5. Improve soil structure 6. Plant root system - infrequent water will force plants to put down deep roots 7. Minimise water loss through drainage