Transcript Wheat Stand Counts - Grain Crops

Wheat Stand Counts
Presentation by:
Chad Lee, Grain Crops Extension Specialist
University of Kentucky
Chad Lee © 2006 University of Kentucky
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Most of the information comes from:
ID-125: A Comprehensive Guide to
Wheat Management in Kentucky
Chad Lee © 2006 University of Kentucky
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Objectives
• Stand Counts
• Tiller Counts
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Three Critical Management Issues
1. Seeding: Date, Depth, Rate
2. N Rate and Timing
3. Fusarium Head Blight
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Scout the Stands
Critical for N Management
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Determining Plant Density
1. Use a yardstick or dowel rod 3-ft in
length
2. Count all plants in the 3-ft length of
row. Record the number.
3. Repeat this in 5 locations across the
field. Record all numbers.
4. Determine the average of the counts.
5. Calculate the plants per sq ft with the
following equation…
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Determining Plant Density
Calculate the plants per sq ft with
the following equation…
Plant number =
Chad Lee © 2006 University of Kentucky
(plant count x 4)
Row width in inches
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Tiller Counts
 Feekes 3: Tillers formed.
 70 - 100 tillers/ft2 adequate.
 Only count tillers (including main stem)
with three or more leaves.
 Less than 70 tillers/ft2: N should be
applied.
Chad Lee © 2006 University of Kentucky
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Planting Date Effect on Tillers
Date
Seeds/ft2
Tillers/ft2
Location 1 (1997-1998)
Oct 14
37
101
Oct 14
23
93
Oct 25
37
58
Nov 7
37
45
Location 1 (1996-1997)
Oct 14
39
83
Oct 14
23
61
Oct 24
39
57
Nov 17
39
50
From: Weisz et al. 2001. Agron. J. 93: 435-442. (NC State University)
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Planting Date Effect on Tillers
Date
Seeds/ft2
Tillers/ft2
Oct 22
39
33
Oct 22
23
31
Nov 12
39
29
Nov 20
39
28
Oct 22
39
39
Oct 22
23
38
Nov 12
39
33
Nov 20
39
22
Location 2
Location 3
From: Weisz et al. 2001. Agron. J. 93: 435-442. NC State University (1996-1997 data)
Chad Lee © 2006 University of Kentucky
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Head Counts
• Feekes 10.5:
– All heads out of sheath.
• 60 to 70 heads/ft2 are ideal.
– 600 heads/yd2
– 35 kernels/head (16 to 18 spikelets/head).
• 55 heads/head will result in adequate
yields.
– 500 heads/yd2
• 90 to 100 heads/ft2 will likely result in
severe lodging.
Chad Lee © 2006 University of Kentucky
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Head Count Effect on Yield
Princeton, 2003
120
120
100
100
Yield (bu/acre)
Yield (bu/acre)
Lexington, 2003
80
60
40
80
60
40
20
20
0
0
0
50
100
150
Head Counts per Square Foot
Chad Lee © 2006 University of Kentucky
0
50
100
150
Head Count per Square Foot
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