Bryan Wilkins
 In South Alabama we generally get enough rain
in June and July to size our pecans.
 We don’t get enough steady rainfall during the
critical August and September nut filling period
to adequately fill the nuts out.
 Irrigation can make up the difference.
 Gives the best use of the available water supply





by controlling the water flow to give maximum
yields with the least amount of waste.
Evaporation loss minimal because the water it
applied below the soil surface
Low pressure requirements=lower operating
costs
Lower labor requirements
Irrigation can be applied anytime
Fertilizer can be injected through the system
 Less disease and insect pressure
 Less wetted area means less weeds and restricts




populations of potential pest hosts No wind effect,
lets you irrigate around the clock
It’s a permanent system
Easily and readily adapted to automatic controls
Provides improved infiltration in soils with low intake
capacity
Allows for the use of more saline water.
 Pecans have a very efficient water transport system
 Developed ability to avoid stomatal closure under
high temps with adequate water
 Pecans are very inefficient users of water
 Require large amounts of water to support optimal
growth and fruit production
 You must have a clean water supply. Adequate and




dependable filtering systems are difficult to provide
Clogged emitters that result from poor water filtration,
algae, bacteria, sulfur, iron and calcium in the water.
Non-uniformity of water discharged from the emitters.
On sandy soils water is not evenly distributed , the water
does not tend to move laterally causing insufficient root
volume wetting and leaching of nutrients.
Mice and rabbits and other animals cause damage by
chewing on the flexible lines.
 Increased Nut




Size/Quality, Nut
Retention
Minimizes Shuck
Decline/Sticktights
Enhances shuck split
Reduces Severity of
alternate bearing
Ability to inject
fertilizer and systemic
insecticides
1 acre inch x 27,154 gallons/acre inch x 7 days = 3,879
gallons/acre/year
3,879 gallons
27 trees/acre
= 144 gallons/tree/day
2 acre inches = 288 gallons/tree/day
March
April
May
June
July
August
September
October
TOTAL
5”
4”
4”
4”
10”
10”
10”
8”
55”
Water about every 6 weeks
 Mid-November
 End December
 First February
TOTAL
2”
2”
2”
6”
 4” Well pumping 85 gallons/minute
 Installed August 2012
 Drip Irrigation
components:
 drip tube with ½ gph
inline emitters spaced
3 feet apart
 2 lines per tree
plowed in at the edge
of the herbicide strip
Cost of System:
Parts and Labor:
$700/Acre
Well: 4 inch 5 HP
$6200.00
 The system is a continuous loop, live feed system.
 It has a 2” main feed line running through the center
of the orchard.
 1½” lines on the end of the rows supplying water.
 All drip lines are plugged connected to the main feed
and the lines on the end of the row.
 This creates a continuous water supply that keeps
the pressure up and waters more effectively all the
way down the row.
 A siphon valve is
installed to put acid and
chlorine through the
system periodically
 Acid will clean any
mineral deposits that
may block the emitters
and chlorine will take
care of algae and
bacterial slime
 2 Treatments: Irrigated and non-irrigated
 5 Replications
 3 Tree plots with the center tree being the
record tree
 Non irrigated trees have the water shut off with
ball valves
 Data to be collected:
 Date of shuck split
 Harvest date
 Percent of shuck tights
 Percent Kernel
 Total Yield
QUESTIONS
Download

Pecan Irrigation-and the irrigation system installation at the GCREC