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TABLE 2
TABLE 3
Recommended Sprinkler Irrigation Starting Temperature for
Various Critical Temperatures and Dew Points
Critical Temperature
Suggest Starting
(Wet Bulb) Dew Point (Air) Temperatures
˚F ˚C ˚F ˚C ˚F ˚C
32 0 32 0 34 1.1
32 0 31 ‐0.6 35 1.6
32 0 29 ‐1.7 36 2.2
32 0 28 ‐2.2 37 2.8
32 0 26 ‐3.3 38 3.3
32 0 24 ‐4.4 40 4.4
32 0 22 ‐5.6 41 5.0
32 0 20 ‐6.7 42 5.6
32 0 18 ‐7.9 43 6.1
30 ‐1.1 30 ‐1.1 32 0.0
30 ‐1.1 29 ‐1.7 33 0.6
30 ‐1.1 27 ‐2.8 34 1.1
30 ‐1.1 25 ‐3.8 35 1.6
30 ‐1.1 24 ‐4.4 37 2.8
30 ‐1.1 22 ‐5.6 38 3.3
30 ‐1.1 20 ‐6.7 39 3.9
30 ‐1.1 17 ‐8.3 40 4.4
Application Rate Recommended for Sprinkler Irrigation Cold Protection
Under Different Wind and Temperature Conditions*
Minimum Temperature
WIND SPEED IN M.P.H.
Expected 0 to 1 2 to 4 5 to 8
Application Rate (inches/hour)
27˚F 0.10 0.10 0.10
26˚F 0.10 0.10 0.14
24˚F 0.10 0.16 0.30
22˚F 0.12 0.24 0.50
20˚F 0.16 0.30 0.60
18˚F 0.20 0.40 0.70
15˚F 0.26 0.50 0.90
*Ext. Circular 287, Florida Agricultural Extension Service, by Gerber and Martsolf.
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