By Thom Luloff, Master Gardener in Training
Amidst the blooms and foliage in our garden lies an unsung group of heroes tirelessly working behind the scenes: detritivores. These animals have a "creepy" reputation—we all know the surprise when we move a pot and then there is an explosive scatter of multitudes of legs!
But aside from the free 'thrill', these critters play an essential role in nutrient cycling, soil health, and our overall garden productivity.
Rove Beetle and Springtail
What Are Detritivores?
Detritivores are organisms that feed on dead plant and animal matter, breaking it down into simpler substances such as nitrogen, phosphorus, and potassium, which plants can readily absorb. This recycling of nutrients ensures that the soil remains fertile and capable of supporting healthy plant growth. Invertebrates such as earthworms, beetles, and millipedes are some of the most common detritivores found in Ontario gardens.
Furthermore, the physical activity of detritivores, such as burrowing and feeding, enhances soil structure. Improved soil structure leads to better water retention and drainage, preventing issues such as soil compaction and erosion. A healthy soil ecosystem, rich in detritivores, is more resilient and productive.
Pill Bug and Millipede
Key Detritivores in Ontario Gardens
- Earthworms (Lumbricus terrestris) are perhaps the most well-known detritivores. These segmented worms burrow through the soil, ingesting organic matter and excreting nutrient-rich castings. Their burrowing activity aerates the soil, improving its structure and allowing plant roots to access oxygen and water more easily (Edwards & Bohlen, 1996).
- Rove Beetles (Staphylinidae family) are another group of beneficial detritivores. These beetles feed on decaying plant material and fungi, helping to break down organic matter and control populations of other pests. Their presence in the garden is an indicator of healthy soil (Newton, 2010).
- Millipedes (Diplopoda class) are often mistaken for pests, but they play a crucial role in decomposition. These multi-legged arthropods consume decaying leaves and wood, breaking them down into smaller particles that microorganisms can further decompose (Hopkin & Read, 1992).
- Springtails (Collembola order) are tiny, soil-dwelling insects that thrive in moist environments. They feed on fungal hyphae and decaying plant material and promote microbial growth, which is essential for nutrient cycling (Hopkin, 1997).
And my personal favourite…
- Pill bugs, also known as woodlice or roly-polies (Armadillidiidae family), are common detritivores found in Ontario gardens. These small, segmented crustaceans are often mistaken for insects due to their similar size and terrestrial habits, but they belong to the class Malacostraca, closely related to shrimp and crabs. Yes! A terrestrial crab—how awesome is that?! Pill bugs are easily recognizable by their ability to roll into a tight ball when threatened, a defensive behavior known as conglobation (also, an incredibly cool word!). They thrive in moist environments, often found under rocks, logs, leaf litter, flower pots, and other debris where they can avoid drying out.
Harnessing Detritivores to Make your Garden more Productive!
To encourage a thriving population of detritivores in your garden (and better soil as a result), consider the following practices:
- Mulching: Apply organic mulch, such as leaves or compost, to garden beds. Mulch provides a habitat and food source for detritivores, promoting their activity.
- Composting: Incorporate compost into your garden. Compost is rich in organic matter and attracts detritivores, enhancing soil fertility and structure.
- Avoiding Pesticides: Minimize the use of chemical pesticides, which can harm detritivores.
- Maintaining Soil Moisture: Ensure that your soil remains consistently moist, as many detritivores, such as earthworms and springtails, thrive in damp environments.
Detritivore insects may be small, but their impact on garden health is enormous. Embracing these crawly creatures in your garden can lead to more productive and healthier plants, making your gardening experience even more rewarding.
More to learn!
To learn more about these amazing creatures, please download Bugdex wherever you get your smart device apps. Bugdex is a revolutionary app introducing the world of insects. It is filled with stunning photographs, interactive animations and a beautiful interface designed to make entomology accessible to all. Learn how to identify major insect groups by recognizing distinctive body features that are beautifully illustrated within the guide. Bugdex is developed by a Danish-Canadian team of entomologists from the Natural History Museum of Denmark and DKB Digital Designs.
All photos in this blog are provided with permission of Dave Cheung, Bugdex.
References:
Edwards, C. A., & Bohlen, P. J. (1996). Biology and Ecology of Earthworms. Chapman and Hall.
Hopkin, S. P. (1997). Biology of the Springtails (Insecta: Collembola). Oxford University Press.
Hopkin, S. P., & Read, H. J. (1992). The Biology of Millipedes. Oxford University Press.
Newton, A. F. (2010). "Staphylinidae Latreille, 1802." In: Beutel, R. G., & Leschen, R. A. B. (Eds.), Handbook of Zoology: Coleoptera, Beetles. Walter de Gruyter.
