It is normal to have different types of vegetation among trees. But It’s an unusual thing in farming. Some researchers also consider growing crops between rows of trees, known as alley cropping, beneficial.
Mature and stable trees are beneficial for the landscape in many ways. They fight extreme weather conditions and climate change. Moreover, they also protect from soil erosion.
Alley cropping has been found to be beneficial in different researches. For instance, alley cropping helps optimize the use of resources, such as nutrients, water, and light. Thus, it guarantees higher yields, hence, higher income.
Recent research explored alley cropping further and was published in the Agronomy journal. This research focused on alley cropping for farming in Minnesota.
A member of the Soil Science Society of America and American society of Agronomy, Joshua Gamble, explains that the competition of crops and trees for resources and strategy development decides the success of alley cropping. The current research evaluates the effects of alley cropping on modifications in soil carbon, root carbon, nutrient stocks, and bioenergy crop root distribution.
Research methodology:
To conduct the study, the research team decided to evaluate different crop and tree combinations in two different fields in Minnesota. The sites they chose were near streams or floodplains.
These sites are often at risk of erosion and flooding. Therefore, these sites are not suitable for traditional farming. However, alley cropping is the most suitable option to prevent such issues.
First, the researchers planted trees in rows. Then they grew grass crops between them. They use two tree species, shrub willow, and hybrid poplar, with several grassland mixtures to evaluate the potential of alley cropping. After four years, they test different parts of the plant, especially roots.
“We found that the tree roots extended up to six meters into the crop alley, which reduced the growth of crop roots and impacted the distribution of crop root carbon and nutrients in the soil,” Gamble says. “In general, poplars were more competitive with the crops than willows. We also found small losses of soil carbon after four years.”
“Because the poplar trees were more competitive than willows, our results suggest that willows may be better suited for alley cropping in the long-term,” adds Gamble.
When the growth of both grasses and trees was observed, it was found that both grow well. This success of alley cropping can be achieved in many ways.
- The first method involves choosing the crops and trees with different rooting patterns. For instance, trees with deeper roots will work perfectly with grass species having shallow roots. The different rooting patterns ensure no competition between trees and grass for nutrients and water.
- The second method involves choosing trees and grass that need nutrients and water at alternate times. For instance, a tree that needs water in spring will make a perfect pair with grass that grows well in the summer.
According to Gamble, various ways could help achieve an optimum relationship between crops and trees. The goal is to optimize the farming revenues and overall yield by best using the available resources.
The researchers claim that their findings provide insight into the ideal tree and crop combinations for alley cropping with bioenergy crops. However, the market for these systems is not very robust right now. Therefore, farmers may take some time to accept these systems.
Gamble hopes to provide continuous income from these farmlands. Moreover, their goal is also to benefit the environment. However, he also mentions that productive crops with alley cropping don’t mean that this system is going to replace traditional grain cropping for fertile soils. They aim to convert only the suitable and less productive soils to alley cropping.
To support this research by Joshua Gamble, the North Central Region SARE program, Minnesota Pollution Control Agency, and the United States Department of Energy came forward.