The tallgrass prairie is a fascinating and truly beautiful native place. Nearly 250 million acres of it once graced the eastern edge of the Great Plains. It was also present in special areas farther to the east, including large stretches of the Choctaw homeland. What had flourished for thousands of years was nearly destroyed in just a 130-year span as the region was colonized. Today, only about 2% of the tallgrass prairie remains.
Last year, we worked hard to learn how to identify the tallgrass prairie plants that have survived/started to come up on the Nan Awaya Farmstead. No doubt, there are some that we missed, but even so, we were able to document 22 native grass species and 63 species of native forbs. Not bad diversity, but unfortunately, most of these plants only grow in small corners of the farm, rather than across it.
There's tons of how-to information available on prairie restoration-that is if you want to plow the land, kill every plant, and do a restoration from scratch. Much less information is available if you want to build existing remnants of the prairie back into something healthy. Over the past 5 years, we've learned that one of the most important keys for doing this is proper pasture management. This means bringing fire and grazing animals back to the land in a variable way, allowing the plants proper rest periods from these forces, and closely monitoring. However, if certain species of plants have been completely eliminated from a landscape, no amount of grazing and fire is going to bring them back. This winter, the Noble Foundation helped us make an assessment of our pastures, and they feel that in large areas, we just don't have enough of a seed bank in the soil for the prairie to restore itself to its full health. Their recommended was to plant more seeds.
In a post last spring, we talked about the ups and (mostly) downs of our previous prairie seed planting experiments. At that time, we were trying out what was a new technique for us, seed bombs. With seed bombs, you package dry seeds into small, round balls of compost/clay, allow them to dry, and push them part way into the soil. The compost/clay mixture is supposed to protect the seeds until they sprout, and then provide a little nourishment to the growing young plant. We made and planted 1,000 seed bombs as an experiment. Although seed bombs are a popular item for sale, we've been able to find very little research into their actual effectiveness, so we promised to share the results of our little experiment.
So far, the results are less than conclusive. This summer, 5 annual sunflower plants sprang up in widely scattered pastures where the bombs had been planted. There was none of this plant on the land before, so the experiment was successful in the sense of returning an important plant species to the landscape. While 5 plants out of 1,000 plantings is pretty underwhelming, the planting was probably more successful than that. Of the number of species that we planted, the sunflower is fastest growing and the most visible. It's likely that young perennial prairie plants did or will come up unnoticed under the existing canopy. We've already seen something similar when we planted seeds for Indian blanket flowers around the farm. None of these plants came up until two summers after the seeds were planted.
This year, we're planting another 1,000 seed bombs, incorporating a few lessons learned that we hope will increase the success rate. Last year, we focused on using locally collected seeds. We did the same thing this year, but made our mixture of seeds heavy on early succession grasses that are specially adapted to our sandy soil, plants such as the aptly named sand lovegrass and sand dropseed. We also added dirt from the area where many of the seeds were collected into the seed bomb mixture in hopes of inoculating the bombs with the proper microbes to help the plants germinate. We planted 500 of the bombs much earlier this year than last, in hopes that the natural freeze/thaw might make for more effective stratification than our refrigerator did. Finally, rather than scattering the planting across the landscape, we concentrated most of it into a 2 acre pasture that can easily be excluded from grazing to give the young plants a better fighting chance. Are these modifications going to unlock the key of seed bomb success?... We'll keep you posted.