Botany lab ten soil analysis
Last year a single LaMotte soil analysis kit was sufficient for the ten person section. A presentation provided directions to all of the groups. An attempt to locate and reorder the reagents failed.
With duplication of the instructions, the Luster Leaf test kits would perhaps be the optimal choice as eack kit can be used by four groups at one time. Each lab pair could run one of the tests and then swap test chambers. The other kits are more clearly intended to be used by a single user. Luster Leaf instructions are also available online.
Medleen waits for the soil to settle
DS and W-Three also used the Luster Leaf test kits.
The potassium test was perhaps a tad difficult to interpret due to opacity.
Karen and Medleen's pH test
Karen reads the directions for the nitrogen test. She is working from a photo of the directions on her phone.
Elavia and Elaine working with the PooTe kit.
Bentrick and Pelma also used the PooTe kit.
Ashley, Jayleen, and Litana analyze and photograph their phosphorus results using the LaMotte test kit.
High levels of Phosphorus
As a result last fall two other soil test kits were ordered, one from Luster Leaf and the other from PooTe. Two Luster Leaf rapitest digital fertility probes and a digital soil thermometer were also ordered.
Where last year all groups used the same kit, this year groups used different kits. The presentation had not been updated to reflect the kits in use. As a result the presentation was not used in class. Whether a presentation will ever again be useful is doubtful.
What was needed was hard copies of the directions for each kit so student groups did not have to share directions. Three groups used the Rapitest soil test kits with the four chambers. One group used the rapitest digital probe - that probe does not provide NPK data and should be set aside. Two groups used the PooTe test. Two groups used the LaMotte kit. Whether there is enough reagent to use LaMotte again is unknown. The mail order Luster Leaf Rapitest four chamber kits worked better than the kits obtained at the local hardware store twenty-five years ago - perhaps the kits in the hardware store had been on shelf for years. Mail order kits for fall 2026 are recommended. These were certainly the easiest to use.
With 22 students this term the recommendation was made to have students partner up with one partner bringing soil to create a more manageable 11 teams.
The small graduated cylinders were not that useful. The Luster Leaf students, three teams, needed 1000 ml beakers and the 2000 ml graduated cylinders to make a 750 ml to 150 ml five-to-one water to soil mixture.
No one used the capped test tubes. The students took turns using the plastic ware provided with the kits. They also had to share instructions.
With duplication of the instructions, the Luster Leaf test kits would perhaps be the optimal choice as eack kit can be used by four groups at one time. Each lab pair could run one of the tests and then swap test chambers. The other kits are more clearly intended to be used by a single user. Luster Leaf instructions are also available online.
The Luster Leaf kits had a thirty minute wait period for soil to settle out the solution for some of the tests.
Merma times a ten minute potassium test using her cell phone
The potassium test was perhaps a tad difficult to interpret due to opacity.
The PooTe potassium test took some time to comprehend how it was meant to be read. The reading involved cupping one's hands around a miniature bottle to block stray light and looking straight down through the liquid to determine opacity. That was subtle. In the above shot the match apoears to be low, but blocking light from the side suggested that the match was actually medium.
PooTe had the best system for Phosphorus, pH, and Nitrogen. Here the phosphorus was high, the pH was 6.0, and the Nitrogen was high.The indicator sticks were a nice system. Easy to read, clear indicators. Like the LaMotte kits, an initial "Floc-ex" tablet is used to prime the system for two of the tests.
The group using the digital Luster Leaf Rapitest finished before their experience could be documented.
They shared their results the board. The Rapitest was purely an exploratory exercise. NPK is combined into a single fertility value.
The fertility rating of 4 is in the middle of the ideal range. This made sense as they had brought in a dark black soil.
The lack of NPK values is problematic from a learning perspective. The recommendation is to not use these again. The lab includes a subgoal of reinforcing NPK as macronutrients.
The cart really helped with moving gear back to the prep room.
The recommendation would be to continue to acquire test kits such that every group would have their own test kit. The NPK reagent kits are preferable as students get too little hands on time with laboratory equipment.
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