Hey there! I’m Alex from MinuteEarth, and I’ve got a fascinating story to share about how bird poop once saved the day for farmers like my ancestors in Sandy Spring, Maryland. Back in the 1840s, their soil was in bad shape and couldn’t grow crops anymore. They tried everything they knew to fix it, but nothing worked. They were about to pack up and move to find better farmland.
Then, they heard about an amazing substance coming all the way from Peru to the port of Baltimore. This magical stuff was called guano, which is basically bird droppings that work as a natural fertilizer. My relatives decided to give it a shot, so they traveled to Baltimore, loaded up a wagon with guano, and spread it on their fields. They were among the first in the United States to try this out, hoping it would save their farms.
And guess what? It worked like a charm! Their harvests jumped from 3 bushels an acre to a whopping 30 bushels an acre. Thanks to guano, they didn’t have to move away to find better soil.
So, what made this Peruvian guano so awesome? Well, it was packed with two super important elements that plants need to grow: nitrogen and phosphorus. These elements are usually found in the soil, but as plants grow, they use them up. When farmers harvest their crops, they take away some of these nutrients, making it tough for new plants to grow.
Guano was a game-changer because it had about 20% nitrogen and 4% phosphorus. This meant that even a small amount could bring back the soil’s nutrients way better than regular manure, which only has 0.5% nitrogen and 0.2% phosphorus.
There are two big reasons why guano is so full of nutrients. First, birds release nitrogen in a special form that, when mixed with their droppings, becomes super nutrient-rich. Second, the dry climate of coastal Peru keeps rain from washing away the nutrients, allowing the bird droppings to pile up and dry into big mounds of guano.
Once Europeans found out about guano, they started shipping tons of it to places like Britain, Belgium, and the US. It made a huge difference for communities like my ancestors’. But after about 30 years, people in Sandy Spring stopped using guano. It wasn’t just because they ran out, but also because they realized how important nitrogen and phosphorus were for plants.
Thanks to this discovery, we started finding other ways to get these nutrients. We began grinding up rocks that were rich in phosphorus and figured out how to get nitrogen from the air, which is about 80% nitrogen. We also learned how to turn nitrogen gas into a form that plants can use as fertilizer.
Nowadays, when farming takes away nutrients from the soil, we don’t have to move our farms to find new, fertile land. Instead, we can bring the nutrients back to our farms, keeping them healthy and productive.
Conduct a small experiment to understand the effect of fertilizers on plant growth. Plant two sets of seeds in separate pots. Use regular soil for one pot and mix a small amount of store-bought fertilizer (representing guano) into the soil of the other pot. Observe and record the growth of the plants over a few weeks. Discuss how the fertilizer affects plant growth and relate it to the story of guano.
Research and create a poster about the importance of nitrogen and phosphorus for plant growth. Include information on how these nutrients are naturally replenished in the soil and how human activities can impact their availability. Present your findings to the class and explain why guano was such a valuable resource for farmers in the 1840s.
Participate in a role-play activity where you act as a farmer from the 1840s discovering guano for the first time. Write a short script or diary entry describing your experiences and feelings about using guano on your farm. Share your role-play with the class and discuss how this discovery might have changed your life.
Investigate the current methods used to maintain soil health and fertility in modern agriculture. Create a presentation or infographic that compares these methods to the use of guano in the past. Highlight the advancements in agricultural science and how they help sustain food production today.
Write a creative story or comic strip that imagines a world where guano was never discovered. How would this have affected farming communities and the development of agricultural practices? Share your story with the class and discuss the potential impacts on society and the environment.
Hi, this is Alex from MinuteEarth. Some of my ancestors were farmers in Sandy Spring, Maryland, and in the 1840s, their soil was deteriorating and could no longer support crops. They had tried to improve it with everything they knew, but nothing worked, so they were going to have to leave to find newer, more fertile farmland.
Then they heard about a remarkable substance that was said to enhance harvests and was arriving from Peru to the port of Baltimore. My relatives placed their hopes in this substance, traveled to Baltimore, and filled a wagon with guano, which is a natural fertilizer made from bird droppings. They were among the first people in the United States to use this dried guano on their farm fields in hopes of restoring their livelihoods.
And it actually worked; according to records from Sandy Spring, their harvest increased from 3 bushels an acre to 30 bushels an acre. They noted that there was no longer a need for their young people to emigrate to newer, richer soils.
What made Peruvian guano so special? It was particularly rich in two essential elements—nitrogen and phosphorus—that all plants need to grow. These elements become depleted in most farm fields because, as plants grow, they absorb nitrogen and phosphorus from the soil. When farmers harvest their crops each year, they also remove some of the soil’s nutrients, making it harder for new plants to thrive.
Guano contains about 20% nitrogen and 4% phosphorus, so a small amount can replenish the soil much more effectively than traditional manure, which contains only 0.5% nitrogen and 0.2% phosphorus.
There are two main reasons guano is so nutrient-rich. First, birds excrete nitrogen in a different form, creating a nutrient-rich substance when they combine it with their droppings. Second, the dry climate of coastal Peru prevents rain from washing away the nutrients, allowing the bird droppings to accumulate and dry into large mounds of guano.
Once discovered by Europeans, guano was harvested and shipped by the ton to countries like Britain, Belgium, and the US, where it significantly benefited my ancestors’ community. However, people in Sandy Spring stopped using guano within 30 years, not only because it ran out but also because it led to the realization that nitrogen and phosphorus were crucial for plant growth.
As a result, we began grinding up rocks rich in phosphorus and nitrogen, which can be derived from the atmosphere, where about 80% of it is nitrogen. We also learned how to convert nitrogen gas into a form that is chemically useful for fertilizing crops.
Today, when the soil loses its nutrients due to farming, we don’t have to relocate our farms to new, fertile soil. Instead, we can bring fertility to our farms.
Guano – A natural fertilizer made from the accumulated droppings of seabirds or bats, rich in nutrients. – Farmers often use guano to enrich their soil because it is a great source of nutrients for plants.
Nitrogen – A vital nutrient for plant growth, often found in the atmosphere and soil, and a key component of fertilizers. – Plants need nitrogen to grow, and farmers often add it to the soil to improve crop yields.
Phosphorus – An essential nutrient for plants that helps them convert other nutrients into usable building blocks for growth. – Without enough phosphorus, plants may not develop strong roots or produce flowers and fruits.
Fertilizer – A substance added to soil to supply essential nutrients that help plants grow better. – The gardener applied fertilizer to the vegetable patch to ensure a healthy harvest.
Soil – The top layer of the earth’s surface in which plants grow, composed of organic matter, minerals, and living organisms. – Good quality soil is crucial for growing healthy plants and crops.
Nutrients – Substances that provide nourishment essential for growth and the maintenance of life. – Plants absorb nutrients from the soil through their roots to grow and thrive.
Crops – Plants grown in large quantities for food, fuel, or other economic purposes. – Farmers rotate different crops each year to maintain soil health and reduce pests.
Farming – The practice of cultivating the land and raising animals for food, fiber, and other products. – Sustainable farming practices help protect the environment while producing food for people.
Birds – Warm-blooded, egg-laying animals with feathers, wings, and a beak, often playing important roles in ecosystems. – Birds help control insect populations and pollinate plants, making them vital to many ecosystems.
Climate – The long-term pattern of weather conditions in a particular region, including temperature, precipitation, and wind. – Changes in climate can affect the types of crops that can be grown in an area.
