Nematodes, also known as roundworms, are a diverse and widespread group of organisms. They can be found in every type of soil and aquatic environment on Earth. Currently, nematodes include roughly 40,000 described species while estimates suggest the total number is somewhere closer to 1 million unique species. Their population sizes can be staggering. Research suggests that there are 60 billion nematodes for every one human and can have millions of individuals in a single square meter of soil. The majority of nematodes are microscopic but certain species have been recorded at nearly 3 feet in length.
Many nematodes are parasites of plants and animals. Several nematode species are important agricultural pests however very few nematodes are known to be marquee pests of urban trees. Managing nematodes as tree pests should be a multi-pronged approach. Injectable nematicides work to control the pathogens inside the plant. Consider combining these treatments with Cambistat to help with water management and soil-applied treatments, like Xytect or Transtect, to prevent secondary insect pests.