Once the flower heads are harvested for each of the experiments the achenes (seeds) need to be separated from the rest of the head (chaff). The achenes are the important part as they will inform the results of the experiments. All volunteers and staff are blind to which experiment is which so that there will be no bias as to how many achenes “should” be present for each experiment. The process of cleaning heads can be involved and each person has their own technique.
The first step is to label two envelopes: one for the achenes and the other for chaff. The label should have the number of the experiment with the twist tie color, your initials with the date, and then chaff or achene. There is a separate datasheet that has each head detailed where you should cross reference the information and initial with the date. (see below for example).
Example of how to label an envelope and cross check the datasheet where you can write notes such as if a twist tie is missing or a different color
While cleaning it is important not to damage any achenes in the process (though this will happen). People use a variety of tools and techniques to clean a head from toothpicks to tweezers. The stem may be prickly so if you are like me you may need use a napkin or gloves to protect your fingers. There may be achenes that were damaged by critters that took a bite but these should still be placed in the “Achene” envelope. The achenes at the bottom of the flower head are called ray achenes and should also be included in the achene envelope. These can be “hidden” and hard to clean so be patient and thorough. Achenes may be have florets attached which can be left on. Separate the achenes and chaff (a strainer/sieve can be of great help) and place them into the appropriate envelope. Once a head is cleaned put it back in the original little brown bag with the twist tie as well as the two envelopes. These finished bags are but into a big box. Once all the heads from one experiment are cleaned the box moves on to the checking process to ensure there are no stray achenes in the chaff or head. “Check” out the next post for more details….
Clockwise: Cleaned head with achenes and chaff separated; Some of our star cleaners Naomi; Susie; Alan. Note in the above photos the little brown bag with a head is taken from the large brown bag and when cleaned placed in the cardboard box.
P.S. Today Susie cleaned the last head collected from 2015! She already started on the 2016 experiments : )
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