unit 9

an example of plant-growing media

• soil

• water

• perlife

• all of the above

which is not organic matter

• leaf mold

• peat moss

• sphagnum moss

• vermiculite

decay of organic matter is caused by

• large animals

• microbes

• rodents

• water

which is not a factor affecting soil formation

• hydrophonics

• gravity

• ice

• water

humans affect soil formation by

• landscaping

• irrigation

• bulldozing

• weathering

the land class with the fewest limitations

• class I

• class III

• class VI

• class VIII

the land classes suitable for field crop production

• I, II, IV, and VI

• I, II, III, and IV

• I, IV, V, and VIII

• I, II, IV, and VII

the horizon that is most supportive of plant growth

• horizon O

• horizon A

• horizon B

• horizon C

the smallest soil particle is

• clay

• gravel

• sand

• silt

a term related to soil structure is

• aggregate

• loam

• silt

• topsoil