Turf Physiology Turf 201

1
Teachers Conference Spokane 2001 Turf Management
2
Presented by Walla Walla Community
College Bill Griffith
3
Thatch The accumulation of undecomposed
or partially decomposed organic matter located
above the soil surface. The thatch layer is
primarily composed of dead and living root and
stem tissue.
4
Problems Associated with Thatch

• Ideal Environment for Turf Pests

• Soft Spongy Thatch Causes Equipment to Leave
  Marks

• The Above Also Causes Scalping

• Rooting can take place in the thatch layer or
  become shallow

• Water Penetration is Restricted

• Nutrient Penetration is Restricted

5
Why Thatch Accumulates

• Rate of Tissue Production is Greater Than the
  Rate of Tissue Decomposition

• High rates of Nitrogen Fertilization

• Low Soil PH

• Compacted, Poorly Drained Soils

• Vigorous Growing Turf Types

6
Thatch Accumulation
lt Thatch
lt Soil
7
Thatch
Student Lab
A. Have ready or go look at several turf
samples of thatched turf along with some
that are relatively thatch free

• Pour a small amount of water on each
• sample, and see how quickly the water
• moves into the soil profile

• Discuss how this affects the movement
• of air, water, and nutrients into the soil
• and root zone, as well as drainage and
• irrigation

8
Controlling Thatch

• Vertical Mowing

• Aerification

• Liming to Raise Soil PH

• Clipping Removal

• Mulching Mowers

9
Controlling Thatch

• Vertical Mowing

10
Controlling Thatch

• Vertical Mowing

11
Controlling Thatch

• Aerification

12
Controlling Thatch
Various Calcium and Magnesium compounds used to
decrease soil acidity and raise soil PH.

• Soil PH

13
Controlling Thatch

• Clipping Removal

14
Controlling Thatch

• Mulching Mowers

15
Controlling Thatch
Student Lab
A. Discuss possible methods for the prevention
of thatch. Have the students formulate a
plan for controlling thatch on a lawn

• Visit some lawn sites and have the students
• make recommendations on corrective
• Procedures for each lawn. A site analysis.

• Rent a de-thatcher and de-thatch a lawn.
• It should be easy to find a homeowner who
• will pay for the rental and make a donation
• to the class for the work performed

16
Controlling Thatch
Student Lab
d. Visit your local golf course and
watch their aerification process. Ask
the Supt. if he would do a sample
area that hasnt been done before to
compare the difference in soil texture.
17
Turf Fertilization
18
Turf Fertilization
I. Fertilizers
Any inorganic or organic substance of natural
or synthetic origin which supplies one or more
of the essential nutrient elements required for
turfgrass growth.
A. Types of Fertilizers
1. Synthetic inorganic a. Ammonium Sulfate
b. Ammonium Nitrate
2. Synthetic organic a. Urea
3. Natural organic a. Sewage sludge b.
Manure
19
Turf Fertilization
I. Fertilizers
B. Desirable Physical Characteristics
C. Desirable Chemical Characteristics
D. Fertilizer Efficiency
1. Effects on the Plant
2. Effects on Turf Management
3. Utilization Factors
20
Turf Fertilization
I. Fertilizers
A. Fertilizer bag numbers
1. As percentages a. N-P-K b. Sometimes
additional nutrients are listed
2. As a ratio a. Amounts of N-P-K compare to
each other
B. Dollar Values
1. Source of material
2. Solubility
3. Formulation
21
Turf Fertilization
I. Fertilizers
C. Student Lab
1. Have samples of labels for the student to
analyze
2. Percentages of N-P-K
3. N-P-K as a ratio
4. Cost comparisons of each
22
Turf Fertilization
II. Fertilizer Application Specifics
A. Converting to Actual N
1. Weight of bag x N in bag Actual N in bag
Example 50lb bag x 22N in bag 11lbs N in
bag
2. App rate in lbs. x N in bag Actual N
applied
Example 4lbs per 1,000 sqft app rate x 22N
in bag .88lbs N per 1,000 sqft
3. These formulas work for total N, or
individually for WSN, and WIN
23
Turf Fertilization
II. Fertilizer Application Specifics
B. Costing of Actual N
1. Cost of bag / Lbs of N in bag Cost of N per
pound
Example 9.00 bag / 11lbs N in bag .82 per
pound N
2. Makes sure that any comparisons are apples to
apples
Factors WIN, package size, and nitrogen
source
24
Turf Fertilization
II. Fertilizer Application Specifics
C. Application Conversions
1. (Weight of bag x N in bag) Bag
coverage in 1,000sqft Pounds N/1,000
Example 50lb bag x 22N in bag bag covers
10,000 sq ft 1.1 lbs N/1,000
2. Some fertilizer bags do not list a specific
application rate, but how much area the bag
is supposed to cover
25
Turf Fertilization
II. Fertilizer Application Specifics
D. Application Conversions
1. (Desired amount of N/1,000 N
in Bag Application rate
Example .5lb N/1,000 sqft 22 N in bag
2.27 lbs application rate
2. This formula allows you, the Turf
Professional, to decide how much N you want
to apply. This gives you the management
control over this area.
26
Turf Fertilization
II. Fertilizer Application Specifics
E. The importance of WSN/WIN

• WSN Water Soluble Nitrogen quickly available
• nitrogen that is immediately or quickly
  available to
• the grass plant as long as sufficient
  moisture is
• present.

• WIN Water Insoluble Nitrogen not immediately
• available to the grass plant because it is
  not as
• soluble and results in a controlled release
  of
• nitrogen.

27
Turf Fertilization
III. Fertilizer Practicum
A. Application Rates
1. Never apply more than .5 lbs WSN/1,000 sqft
at any one application. a. Prevents
excessive shoot growth and minimizes burn
potential
2. Figure your application rate based on the
desired amount of WSN a. Desired
WSN/1,000 sqft / N in bag App rate
3. Figure the amount of N applied a.
Application rate x N in bag Amount of N
applied b. Do for WSN - WIN - Total N
28
Turf Fertilization
III. Fertilizer Practicum
B. Student Lab
1. Have the student figure the following
a. Amount of N in each of the samples used earlier
b. Amount of WSN and WIN
c. Amount of WSN/WIN/Total N applied at the
recommended application rate
d. Application rate based on applying .5 lbs. of
WSN/1,000 sq.ft.
e. Amount of WSN/WIN/Total N applied using d.
above
f. Cost comparison of each fertilizer
29
Presented by Walla Walla Community
College Bill Griffith
30

• Contact us

Bill Griffith
Walla Walla Community College 500 Tausick
Way Walla Walla, WA. 99362 509-527-4269 bill.griff
ith_at_po.ww.cc.wa.us