Field Notes

<--2016-04-13 15:45:00 | 2016-05-12 11:35:00-->
Other sites visited today: West Pond | East End | Twitchell Rice | Mayberry
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Twitchell Alfalfa: 2016-04-28 12:50:00 (DOY 119)
Author: Elke Eichelmann
Others: Dennis Baldocchi, Kyle Hemes

Summary: Standard data collection. Did soil respiration and spectral. Replaced FR 2cm CO2 probe.

Arrived at 12:50. Sunny, clear, windy day. The alfalfa was recently cut. They were baling at the west end of the field when we arrived on Twitchell Island in the morning. We asked Bruce and his brother who were out there if they have an estimate for the yield, they counted the bales in what they estimated to be about one acre: 34 bales per acre, 100 pounds per bale.

Cleaned the radiation sensors. Did not clean LI7500
Collected USB GHG data, swapped Compact Flash card for met data, collected soilCO2 data, collected radiation met data, collected camera card pictures. All looks good.

Did soil respiration, did spectral measurements with one reference every 5 to 6 samples. Clipped the Alfalfa around the soil and radiation sensors, but did not do clip plots, since the alfalfa was just recently cut.

Measured canopy height, only had an imperial measuring tape, so all in inches:
6 inches 8 inches 7 inches 8 inches 6 inches 4 inches 7 inches 7 inches 7 inches 10 inches 8 inches 6 inches 4 inches 5 inches 4 inches 3 inches 3 inches 6 inches 6 inches
Need to bring a new measuring tape next time.

Changed 2cm FR CO2 probe, new probe in field sn GP20140084, old probe taken out of field sn GP20140023. New probe seems to be reading sensible numbers.

LI7500 readings:
CO2 392.99
H2O 523.3
SS 96.667
T 23.35
P 100.99

hay was cut and baled. We saw about 36 bales in a strip that was about 2 acres, or 900 by 100 feet. each bale is about 100 lbs

Veg Height (cm): Tape measure from ground to top of plant - Recently cut
15, 20, 18, 20, 15, 10, 18, 18, 18, 25, 20, 15, 10, 13, 10, 8, 8, 15, 15, avg = 15.3, stdev = 4.63

3 photos found

TA_autocam_20160429_1345.jpg ( 2016-04-29 13:45:02 ) Full size: 1920x1440
Maybe around 100 hay bales on an alfalfa field