Key Terms for soil

Question 1

Tilth

Answer 1

Crumb structure of seed bed

Question 2

Friable

Answer 2

Readily form crumbs

Consistency of soil after its been worked

Question 3

Soil structure

Answer 3

Arrangement of particles in soil

Question 4

Soil texture

Answer 4

Usually defined by proportion of particles found

eg: sand, silt,clay

Question 5

Soil horizon

Answer 5

specific layer in soil

found by digging a pit

Question 6

Top soil

Answer 6

uppermost layer
normally moved during cultivation
can be dark due to decomposed OM it contains

Question 7

Sub soil

Answer 7

layer below cultivated layer
lighter in colour
less OM

Question 8

Saturated

Answer 8

Soil has all pores filled with water

Question 9

Saturation point

Answer 9

Water filled all pores-there is no air in pores

Question 10

Field capacity

Answer 10

Amount of water a soil can hold against gravity

think of a drained/unsqueezed sponge

Question 11

Permanent wilting point

PWP

Answer 11

The water content of a soil WHEN a wilted plant doesnt recover overnight
(not enought water at root zone)

Question 12

Temporary wilting point

Answer 12

commonly when theres strong drying conditions

(good drying day) plants recover as temps drops and the rate of transpiration falls.