Nematodes and Strulch - a good example of the Contemporary Integrated Crop Management (IPM) approach to reducing the use of pesticides.
A nematode is a microscopic worm - Strulch Organic garden mulch
Using nematodes and Strulch to keep slugs under control is a good example the contemporary Integrated Crop Management (IPM) approach to reducing use of pesticides. IPM is an ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.
Controlling Slugs in Your Garden
Using Nematodes can be an effective way of controlling slugs in your garden but results can be patchy an unpredictable. Here are a few tips on how to get the best out of using nematode control methods.
Nematodes are microscopic worms that are well adapted to living in soils. The nematodes used in commercial slug control products are specially selected strains of parasitic species which seek out slugs in the soil, invade and multiply in the slug body and eventually kill the slug by eating them from the inside out (think of Alien film series). Soil inhabiting nematodes have evolved a specialised method of moving through soils by clinging on to the water films that surround soil particles. Their mobility and effectiveness is greatest in well structured, open and particularly sandy soils that are kept moist so that there is a thin film of water kept around the soil particles. Nematode mobility and effectiveness is greatly reduced in heavy clay soils which are compacted, particularly when they are hard and dry.
Making sure that the soil is well cultivated and moist before applying nematodes is a good first step to getting the most of nematode slug control. However, covering the surface with a layer of Strulch after treatment is an excellent way of keeping the soil moist so the nematodes can do their job of seeking out and attacking slugs.
Should I use nematodes or Strulch to prevent slug damage in my garden?
The questions should not be either/or since the use of both can be complementary. Strulch works by deterring adult slugs from moving in from outside to graze on susceptible plants and lay their eggs in the soil. If your soil is already heavily infected with slugs then applying Strulch may not always be sufficient to prevent slug eggs from hatching out and attacking plants without having to move in over the soil surface. Combining nematode control with Strulch can be beneficial in these circumstances. Once the nematodes have done their work in removing slug infestation in the soil, the Strulch will deter invasion of new slugs from outside the controlled area.