Decomposition as Production
Decay. Rot. Spoil. Fester. Putrefy. Decompose. These are all words we don’t normally associate with a beautiful garden, but each are vital to the health of a plant or crop. Although it takes on many definitions, decomposition can be understood as the separation of a thing “into constituent parts or elements or into simpler compounds” (Merriam Webster, 2025). If we use this definition as a way to understand decomposition within soils, we can reframe it from being a negative term associated with death to an adjacent term for health and production. When a plant undergoes decomposition, there is significant work occurring behind the scenes thanks to a chain of microorganisms inhabiting the soil. One of these microorganisms, the friendly nematode, is a significant contributor to that decomposition.
Bacterial (free-living) nematode
At the Kinney Center, the kitchen garden is host to 64 free-living nematodes per 100 cc of annual garden soil and 84 free-living nematodes per 100 cc of perennial garden soil. As a result, we are effectively surrounded by hundreds of small but mighty decomposers! These “invisible” free-living nematodes are notorious for their role in decomposing organic matter to recycle nutrients in the soil. Despite their predatory reputation, free-living nematodes feed on the bacteria and fungi which decompose organic matter. With their presence, free-living nematodes are able to hasten the decomposition process beneath plants. Free-living nematodes are able to get minerals and nutrients from bacteria, fungi, and other substrates into the soil where plant roots can uptake them (EDIS, 2022). Thanks to their recycling habits, free-living nematodes are instrumental in providing adequate nutrition to our plants. Without free-living nematodes, or in minimal numbers, plant and soil health is nearly destined to suffer.
When we look beyond the surface of our soils, we may conjure up images of rotting plants in the face of hungry nematodes. However, it is critical to recognize that not all nematodes are bad in a balanced biological system. With the presence of free-living nematodes, we are also in the presence of beautiful rotting occurring within our soils. Free-living nematodes help release excess nitrogen in the form of ammonium for plants, as well as contributing to nitrogen mineralization. Due to this, plants are able to effectively conduct photosynthesis. These nematodes also help to distribute bacteria and fungi through the surface and their digestive systems within the soil. Simultaneously, providing a source of food for other compositing invertebrates, including centipedes, fly larvae, and mites (EDIS, 2022). Free-living nematodes also help to prevent disease, which is beneficial to overall soil health. Thanks to the hard work of our friendly nematodes, we need to embrace the beauty behind rot and decomposing matter. Not only is it valuable to other microorganisms, it is significant to the health and wellbeing of our soils, plants, and ultimately the entire food web.
Why do we want our plants rotting?
Rot and decay are not unique to the discolored, limp plant left in your garden from the summer. It also includes the separation and redistribution of resources beneath that plant propelling through the soil. Although it cannot be seen with the naked eye, rotted plants make for happy microorganisms. Decomposers like nematodes are commonly unseen, leaving humans to ignore and often neglect the health of the soil for the sake of external aesthetics. This project helps to illustrate the biological happenings beneath the surface. Within our soils, microorganisms are taking full advantage of the plants we worry over. Nematodes in particular are busy working with the roots, bacteria, and fungi which fill the soils we carelessly trample. Through the work of nematodes and other microorganisms, we are able to contribute to a larger ecological cycle which prioritizes not only what is above, but also below, the surface.
Fallen leaves and branches providing cover and organic matter for soil. Winter 2024.
When we leave a “dying” plant to decompose in the soil, we can help to reduce plant-parasitic nematodes and improve soil structure. This occurs because compost and organic amendments can help to suppress damaging nematode populations within the soil (EDIS, 2022). In fact, the greater amount of organic matter through rotting plants provides fodder for fungi and bacteria to break down. Thus, creating more food for free-living nematodes. Although it may appear rough on the outside, we are encouraging healthy organismic activity on the inside.
Nematodes are influential throughout the soil profile in many ways. Nematodes can help to regulate other soil organism populations, provide food sources for soil organisms, mineralize nutrients into plant-available forms, and consume disease-causing organisms (Curell, 2013). Overall, there are many benefits to healthy nematode populations in soils.
The prosperity of our plants challenges us to awaken our minds to believe in the power of the invisible. We have an obligation to learn and understand nematode habits in conjunction with the bigger soil picture. All too often we forget that plant health and yield productivity are connected with microorganisms activity and population. Although we cannot see them, they are still constantly working to cultivate the land we know and love. The invisibility of decomposers becomes not so invisible when our perennial plants turn from rotted stalks into lush flowers each spring. We are all too quick to disregard the decomposition process in favor of perceived cleanliness or beautiful looks. When we take the time to dig and think at a distance, we are deepening our relationship to the land and soil. We are reminding ourselves that the future of our landscape is linked to the very busy but invisible work of today’s and yesterday’s nematodes.
References:
Ask IFAS - Powered by EDIS. “Eeny-012/IN138: Soil-Inhabiting Nematodes, Phylum Nematoda.” Ask IFAS - Powered by EDIS, edis.ifas.ufl.edu/publication/IN138. Accessed 9 Mar. 2025.
Christina Curell, Michigan State University Extension. “Are Soil Nematodes Beneficial or Harmful?” MSU Extension, 21 Jan. 2022, www.canr.msu.edu/news/are_soil_nematodes_beneficial_or_harmful.
“Decompose Definition & Meaning.” Merriam-Webster, Merriam-Webster, www.merriam-webster.com/dictionary/decompose. Accessed 9 Mar. 2025.