Soils Lecture 2

Question 1

“We are rooted to the air through our lungs and to the soil through our
stomachs. We are walking trees and floating plants.”
Who said this?

Answer 1

JK, YOU DON’T NEED TO KNOW, but in case you were wondering: J Burroughs

Question 2

What soil temperature do plants grow best in?

Answer 2

40-50 degrees Fahrenheit

Question 3

Difference between cool and warm season grasses?

Answer 3

Cool season grasses start early season growth but shut
down as it gets too warm (different chemical reaction chain in photosynthesis)
Warm Season grasses start after temps allow their photosynthesis reactions to step up

Question 4

Plant roots must have oxygen to do what?

Answer 4

respire. So that root hair cells can transfer
nutrients into the plant
-Roots respire and give off CO2 in the soil both day and night

Question 5

Mycorrhizae

Answer 5

Fungi hairs in symbiotic relationship with roots

Question 6

Aeration of soil can be increased by…?

Answer 6

better drainage, fossorial (underground

dwelling) animals, earthworms, etc

Question 7

Soil Matrix

Answer 7

The arrangement of air pockets to soil particles – usually 50/50

Question 8

How many pounds of water is needed to produce 1 lb of plant growth?

Answer 8

From 200 to 1000 lbs of water

Question 9

Annual crops

Answer 9

Crops that must be re-seeded each year (corn and soy beans)

Question 10

Perennial crops

Answer 10

Crops whose roots can overwinter and continue growing the next season
(grasses and alfalfa)

OVERWINTER (verb): to last through or pass the winter

Question 11

Vertisols

Answer 11

Clays that shrink and swell. Can’t build anything on.

Question 12

Erosion

Answer 12

Soil loss by surface removal
- It is said that 2 bushels of soil are lost to
erosion to every 1 bushel of corn.

Question 13

Pollution

Answer 13

Where toxic materials are left on

or in the soil by unregulated or illegal use

Question 14

Salinization

Answer 14

The result of salt increases

in the soil due to irrigation over a number of years

Question 15

Acidification

Answer 15

• Can happen when too much fertilizer is added to the land

- Occurs naturally very slowly as soil is weathered, but this process is accelerated by productive agriculture

Question 16

Urbanization

Answer 16

The spread of city construction that covers farms, fields, and forests nearby and spreads outward
- Urbanization is taking some of the best of our farms
and open areas and converting them to hardspace for homes, stores, and parking lots.