A major issue in observation studies is that we often don’t always know what the potential confounding factors may be. In the soil fertility experiment we started a few weeks ago the confounders have overcome the experiment to the point that it was almost impossible to tell what was happening.
First, the planter was visited by our resident rodents, the hopping mice that peek out at us from the bushes and love to steal tasty treats. They dug out many of the seeds and presumably ate them.
Next, maybe due to the delicious rodent perfume worn by our mice, a cat visited the planter and dug through one side of the box creating a large mound containing who-knows-what sort of catly gifts. And that was before the huge storm that blew everything around and even washed some of the soil right out of the planter and onto the plastic around it.
In spite of all of this, a few things did actually sprout. If you look carefully at the East side of the soil test bed, the “Tomato Soil” side, you can see how we counted twelve sprouts the last time we recorded data from this experiment. But 12 sprouts of what, exactly?
At least three of the sprouts were squat, strong-looking stems with rounded leaves on them. The rest were spindly stems with elongated, pointed leaves on them. Only the first three were a match to the pea patches growing in two nearby planters.
So, since this a really great experiment concept, and we already have the nicely amended (thanks for all your help, Cat!) soil on one side and the do-nothing-to-it “Tomato Soil” on the other side, we decided to replant this experiment to see if we can get a less confounded idea of what happens.
The bed was smoothed on the West side, and the cat pile was carefully removed. The bed was then replanted with 1 oz. of ‘Alaska’ (Earliest of All) peas, also known as Pisum sativum var sativum, packed for 2009. These were planted equally on the two sides but we decided to allow the existing pea sprouts to stay. They were marked so we can take them out of the data if we choose to.
Then the bed was carefully covered with burlap and cages to discourage visitors. Unfortunately, this morning there seem to be a whole lot of holes in the burlap that weren’t there when we put it on! Kids weren’t the only ones out trick-or-treating last night. We’ve been raided by varmints! (I”m sorry about all those things I said, Cat. Please come back to the garden. We need you! We’ll plant more catnip, I promise!)
It looks like at least a dozen holes were dug into the planting area last night. There’s no way to tell if the mice are eating the new seeds or the old seeds that might be still left in the soil. But there are certainly some of the seeds still undisturbed in the planting area.
In order to try to salvage this experiment we grabbed a few things we had around the garden and built a mesh wire cage over the planter like the one we use for the carrots’ Fort Knox. Hopefully this will give the peas a chance to sprout and grow through the tender and delicious stage. We noted that the peas that we started weeks ago who were sitting nearby in their nursery packs waiting to be planted are undisturbed.
We didn’t have a large enough piece of hardware cloth to cover the entire bed so we covered an equal amount of each side and will leave the area with the most rodent damage exposed for now. Maybe that will help keep the mice from breaking into the seeds we are trying to save and then we can plant it with another crop in a week or two when we see how things germinate.