Fall 2016 Leaf litter was collected 4 times so that Melany Fisk could analyze nutrient concentrations. Dry litter can be collected in paper bags. But wet paper bags can break and lose our samples. It was pouring rain on the 3rd collection date, so those samples were collected in plastic. For those of you who have been spending time trying to sort leaves that were collected very dry, these look easy to work with!
Some of the samples are so wet, you can see the dissolved organic carbon that leached out. We were concerned about transferring these to paper bags to dry.
Trial and error has led to the development of procedures for drying in plastic, which will save time and the possibility of labeling errors. Permanent marker tends not to be so permanent on plastic, making the bag labels sometimes hard to read. To solve this problem, we printed labels and placed them inside the bag with the sample.
Plastic bags don’t wick water like paper and therefore drying the samples can be a challenge. If the plastic bags fall over and close, they tend not to dry. The proper drying of samples in plastic involves arranging them in rows with the the rim of the individual bags folded over to ensure that the bags stay up right and open to allow airflow while drying.
The bags are placed in a box, which also helps to minimize the time needed to place them in the oven. If the oven is open too long and cools off, it can overshoot our target temperature when it heats up again.
We tested both types of plastic bag overnight before we put any samples in the oven. We didn’t want melted plastic and lost samples!
Gretchen will be stopping in twice this week to weigh bags and determine how long it takes to dry them in plastic. Which is better, paper or plastic? Stay tuned.
Today we started out by investigating the effects of a mysterious dip in the drying oven’s temperature down to 48 C. To check to see if this would affect our data, Nick weighed a few samples and weighed them again when they got to 60 C. The differences were 0.5% – 1.5% of the mass, so we determined this to be ultimately insignificant.
While working we uncovered a cadre of copycat samples (Griffin says its more like identity theft than copycatting), with labels that have already been entered into our data sheet! These samples (HBO-1-A1, and some Power Cores) have been defying our collective investigative ability, but we’ll be sure to pick this up with a fresh angle next time.
Athena, Ed, Nathan, and Vizma spent all 4 hours on a single soil sample in a show of sheer determination.
Today we made a discovery in examining the leaf litter from the HBO4 Y3 subplot. It’s a pretty strange finding, exact identity unknown. The discovery of this squishy, web-wrapped thing presented a mystery, and its unwrapping caused some of the lab volunteers to cringe. When its shiny black exterior was uncovered, the plot only thickened, as none of us were able to tell what exactly it was that had made its way into our leaf sample. Our best guess is a chrysalis. It is pictured below, first in its shawl, and then with its covering removed and a ruler for scale.
-Anna Canny, Lab Volunteer
Once upon a time in a land not so far far away an interesting discovery was made. While hard at work sorting JBO leaf litter samples some high school and college students noticed some strange creatures hidden among the sugar maple leaves. What were these creatures you ask? Well we believe they are Maple Trumpet Skeletonizer Caterpillars. Pictured above are the remnants of the caterpillars that have been found. Also shown above are maple leaves that have been skeletonized by these caterpillars. In light of this discovery, a high school student decided to look into these caterpillars further for a science fair project. Within the JBO stand there are multiple different fertilizer treatment plots. We are looking to see if these treatments of nitrogen/phosphorus have an effect on the number of caterpillars seen. Stay tuned for further information and results from this ongoing project!!
Note the birch seeds in the background. For scale.
11/29/15 Ruth, Long, Mona, Noura, Nada, Vizma, Nick
Long and Mona worked on reweighing samples from last weekend, to test whether they are dry enough to weigh after one day in the oven.
Nick worked on the 4th pit root data, comparing his results to Abby’s and checking discrepancies.
Nada did a root sample: JBM 2 50-70 (4) 6/8/10
Vizma and Noura did a leaf sample: JBO-1-C3
They started looking at ways to characterize the Mystery Caterpillars that they have been picking out of sugar maple leaves. It will be easier to count them while sorting the leaves. They are dry now and breaking.
Thanks to Bernie Reschke, we got coat hooks! There’s even a shelf on top! We realized that we needed to get some after a very overcrowded Saturday with 14 people and 14 coats. We’ve also got some right outside the door.