Our final project for our Ecological Biology class was the creation of soil sponges. Anika and I learned first, what they are, second how they can help an ecosystem (or in this case a few ponderosa pines that were in bad shape), and third how to create them. For anyone who doesn’t know what a soil sponge is, it is essentially a hole filled with “sponge like” materials that helps to hold water, channel water, and slowly release carbon into the surrounding soil. They are able to help an ecosystem because they are able to channel water to separate areas, and slow water down as they are both porous and absorbent. The idea of this is pretty simple right? However, creating these sponges was a whole other story…
On Easter Sunday, 2014, I, along with Anika, our teacher Mrs. Beamish, and several sustainability coordinators from around the state began the creation of soil sponges outside at the Desert Oasis Teaching Garden. Christian (who was the “teacher” of this workshop) had already gathered the necessary tools (pitchfork, shovels, rakes, wood chips) to begin the process. For a good while we stood and listened to Christian while he talked about the limestone and the unique soil composition in New Mexico. After about 30 minutes or so, we began work on the actual soil sponges themselves.
The initial steps to creating the soil sponges were to dig holes that were about the size of a bathtub (about 2 feet by 5 feet and 2.5-3 feet deep). Using an “A” frame (pictured below), we were able to decide in what regions the ground was most level going lengthwise with the holes. This was because the sponge is designed to help channel the water, and if it is not level, then the channeling would not utilize the entirety of the sponge, in that the water would travel to a corner and be released only in that area. After planning, it was time to begin digging.
What we hadn’t realized would be the toughest part of this was the digging. Christian was attempting to begin the digging of the first one (which ended up being the hardest) and soon found trouble in the initial steps of simply taking the grass layer off of the top of the soil. Even after taking the grass off in the beginning, it didn’t get any easier. What Anika and I found out later is that this is do something called caliche or scientifically calcium carbonate. This made the ground pretty as hard as cement. One of the sustainability coordinators at the time remarked “This may be easier if we had a stick of dynamite”. It was just that hard.
In the beginning of the day, we all saw it nearly impossible that we were ever going to make these holes 3 feet deep. However, as we quickly found out, soaking the soil seemed to help dissolve the calcium carbonate as it is a salt. For the day, this seemed to make our lives a little bit easier in terms of digging. After the initial day however, Anika and I found it much easier to take the topsoil and Kentucky Blue grass off, and thoroughly soak the area and leave it over night. Sadly, this day was very slow going, and we were only able to get 2 sponges completely finished, and have one other hole that was about half way finished.
The next phase in these soil sponges was to add paper. Luckily for us, our school newspaper seems to print too many copies of “The Advocate”, so they made a perfect base for the sponge. Christian, who was the expert and has been making these sponges for years, remarked that you can use anything that would soak up water from paper to old cotton clothes. In this case, we solely used paper to fill these holes. After the holes were filled, we covered the paper in wood chips, so that now, we had filled in the hole completely. Next, Anika and I jumped on the wood chips to compress the paper. Lastly, the paper was thoroughly soaked throughout to help compress it even more and to keep it all together and begin the release of carbon.
In the end of the first day, 2 sponges were created, but by the end of the project through the work of Anika and I (class time) and through the help of some classmates during their CIA (Chargers in Action) shifts, we created a total of 5 sponges. Hopefully, this will be enough to save these trees, and if not, it will help the next trees that are planted after the ponderosas have passed.
Photo Credit to K. Beamish. (yes, all of them)