End of unit 4....Start of Unit 5

Question 1

What soil properties influence water movement in the soil?

Answer 1

• Texture and Pore Size
• Soil Structure
• Compaction

Question 2

What kind of pores are the majority in a sandy soil have?

Answer 2

Macropores

Question 3

What soil structures make it easier for water to move?

Answer 3

Granular and Blocky

Question 4

What soil structures make it harder for the water to move?

Answer 4

Prismatic and Platey

Question 5

At some point, the root can no longer pull any water into the plant for usage….why does this happen?

Answer 5

The force of the roots pulling the water in is weaker than the force of adhesion and cohesion that are keeping the water attached to the soil particle.

Question 6

What is Soil Water Tension?

Answer 6

Ease with which water can be extracted from the soil

Question 7

As soil dries, soil water tension ________.

Answer 7

increases

Question 8

It’s easier for a plant to extract water held at a _______ tension.

Answer 8

lower

Question 9

What do Tensiometers do?

Answer 9

Measure soil water potential

Question 10

When did the USGA start using agronomists to do research? What is this group of agromomists called?

Answer 10

1920’s

The USGA Greens Section

Question 11

Originally….Why were golf greens built to USGA Specifications?

Answer 11

To solve issues with compaction and drainage

Question 12

What are some issues with maintaining a sand based green?

Answer 12

• Low water holding capacity
• Low nutrient holding capacity - Low O.M.

Question 13

Why was the USGA Greens Section introduced?

Answer 13

It was formed to do research to try to understand the problems that superintendants are dealing with in hope of finding solutions. They will do course visits and alanyze the golf course.

Question 14

When were the USGA Green Specifications originally published?

Answer 14

Early 1960’s

Question 15

What are the key additions to a green when using a USGA Spec.? Besides native soil….

Answer 15

• Drainage - drain pipe & pea gravel
• Choker Layer
• Greens Mix

Question 16

What do layers of a soil do to water movement?

Answer 16

• They impede water movement
• (slows it down)

Question 17

What does the Choker layer do?

Answer 17

• Creates a perched water table by impeding water movement and prevents migration of your sand mix into the drains

Question 18

what is the problem with the “modified” USGA spec. greens?

Answer 18

• They built them without the choker layer and the greens failed because the sand would migrate to the drains and the drains stopped working. Fail!

Question 19

USGA has modified their specifications allowing greens to be built without the choker layer….But, What has to happen?

Answer 19

• The greens mix and the gravel have to Bridge.
  
  • They have to be tested in a lab to confirm they will work together (bridge) without having the sand migrate through the gravel.