Leaf Area Sampling

A method for sampling leaf area was tested at Sunrise Orchard on May 23 in the Horticulture study plot (Sunrise 2D).  The two middle trees from the middle Fuji row in each replicate were sampled by picking 5 shoot and 5 spur leaves from 6 zones on each of the the two trees.  Each tree was divided into zones of approximately 1 meter in height on both the East and West side of the tree (6 total zones: Top West, Top East, Middle West, Middle East, Bottom West, and Bottom East).  Shoot and spur leaves were combined and collected in paper bags, transferred back to the lab and measured using a Licor leaf area meter.  The leaves from each zone were run across the leaf are meter and the average area per leaf calculated (Total Area/# of Leaves).

SSCDS Leaf Area Methods

SSCDS Leaf Area Methods

SSCDS Leaf Area Zones

SSCDS Leaf Area Zones

The chart below shows the average leaf area per zone.

Average Leaf Area per Zone

Average Leaf Area per Zone

Leaf area measurements will be used later in the season in combination with applications of Tartrazine dye to help assess coverage of the SSCDS in comparison to an Airblast sprayer.

Overview of SSCDS Plots at Sunrise Research Orchard

The SSCDS test plots at the Sunrise Research Orchard located outside of Wenatchee, WA are one acre in size and divided into three treatments:  1. SSCDS System; 2. Airblast Comparison; and 3. Untreated Control.  The treatment plots are replicated four times – each replicate is 0.03 acres in size.  Each of the treatment plots are separated by four buffer rows.

The water is carried on a 1″ poly line attached to the 6′ trellis wire.  There is approximately 300′ of 1″ poly in each plot.  The 1″ line is looped from row to row so that the input and output lines can both be attached to the SSCDS spray Rig for pumping and recapturing pre-mixed spray materials.

1" Poly Tubing for Sunrise Orchard

1″ Poly Tubing for Sunrise Orchard

There are 104 emitters in each SSCDS replicate.  Emitters are located on 48″ risers (10′ from the ground), 24″ risers (8′ from the ground), 0″ drops (6′ from the ground), and 24″ drops (4′ from the ground).  Each emitter of the same height is separated 6′ horizontally.

SSCDS Emitter Arrangement for Sunrise Research Orchard

SSCDS Emitter Arrangement for Sunrise Research Orchard

The emitters are from Jain irrigation Modular Group 7000 Series with a Violet Nozzle and a Yellow Flat Spreader.  Each emitter is accompanied by a pressure compensating device (check-valve) that opens when pressure reaches approximately 20 psi.  Each emitter emits 9.2 gallons/hour at 30 psi.

Jain Irrigation Modular 7000 Series with LPD

Jain Irrigation Modular 7000 Series with LPD