The What: To kick off our second lab of the semester we (DYLAN and DEVIN) are going to be DISCOVERING DIRT.
The Why: Dylan and I along with the rest of the Birmingham-Southern College BI 304 students will be trying to determine an unknown microbe in soil samples taken in random locations across the Birmingham-Southern campus.
The Where: The sample that Dylan and I will be handling was taken outside of the Stephens Science Center first floor entrance.

Our sample was taken from the surrounding soil at the base of  an Oak Tree outside the Stephens Science Center first floor entrance. In order to collect an adequate sample Dylan and I had to brush away all leaves, twigs, and other possible debris that had collected around the base of the tree. Doing this ensured that our sample was purely soil with no additional materials.

The soil that we collected was dense and somewhat moist, but not wet too wet to inhibit the experiment. The sample was surrounded by a few patches of grass and a few groups of dandelions. The fact that this sample is surrounded by plant life will provide more of a variety of bacteria because it will contain the roots of the nearby plants. This soil that contains plant roots is called rhizosphere, and luckily the location we picked had an abundant amount of rhizosphere.

The How: In order to collect our sample we had to obtain:
1.) 1 trowel.
2.) 1 scoopula.
3.) 2 alcohol wipes.
4.) 15 mL conical tube.
5.) 1 pair of latex gloves.
6.) 2-3 paper towels.
Collecting the Soil: to collect our soil we took our trowel and dug approximately 5 inches into the ground, making sure not to surpass a six inch depth. Once we had created our hole and collected our sample with our scoopula we placed the soil into our sanitized 15mL conical tube, then headed back to the lab!
Back in the Lab...
Sample Preparation: once back in the lab Dylan and I weighed out approximately 0.5g of soil in out balance and mixed it with 50mL of sterile water in a 50mL conical tube. The tube was then shaken to mix up the soil particles with the water and inverted to ensure a thorough mixing. Once all of the mixing was complete the sample was set aside so the soil could collect at the bottom of the conical tube...and now we wait...
Assessing Cultural Microbes: Dylan and I took 5 different microfuge tubes to carry out our dilutions (ranging from 10^-3 to 10^-7). Once we had completed all of our dilutions we set up 5 Tryptic Soil Agar Plates with corresponding soil dilution concentrations. Each plate received one drop (100 microliters) of its corresponding solution. Once the drop had been applied to the plate it was spread out with a freshly sterilized spreader, and was then closed and ready for incubation at room temperature.
      Once all of the Tryptic Soy Agar Plates had been covered and set aside it was time for the beautiful Rose-Bengal! The Rose-Bengal plates suppress bacterial growth, which was used in order to control the fast-growing bacteria colonies from taking over the plate. This single Rose-Bengal Plate was covered in the 10^-4 soil solution and covered for incubation.

Two Types of Agar Plates Directly After Addition of Soil Dilution Solutions

One of five Tryptic Soy Agar Destination Plates. This
plate contains the 10^-3 soil dilution (the most concentrated
of all of the dilutions). 

One of one Rose-Bengal Agar Plates. This plate
contains the 10^-4, which is the second most
concentrated dilution.

Check us out next week! Will there be growth...?