Nematodes on plum roots can cause serious damage. These parasitic, microscopic worms live in the soil and feed on tree roots. Some are more damaging than others and infestations can be spotty throughout an orchard, but overall the worms can cause loss of vigor, reduction in fruit yield, and ultimately death of branches or entire trees.
About Plum Tree Nematodes
Nematodes are microscopic roundworms that are not uncommon in the soil. Plum trees and plum rootstock are susceptible to damage from root knot nematodes. This type of nematode burrows into the cells of roots and stays there, feeding for its entire life.
Signs of root knot nematodes in plums include a root system that is poorly developed. Above the soil, trees will show a general lack of vigorous growth, smaller leaves, and twigs and branches that die back. By harvest time, you will see a lower yield. You may also see cankers and blighted buds, leaves, and flowers on affected trees. It is not uncommon to see root knot nematode signs in some trees but not others.
Young trees planted in soil that is infested with nematodes are most vulnerable to the worst effects of these pests. They can show stunted growth and either die soon after transplanting or continue to show poor growth and low yield of fruit.
Plum Root Knot Nematode Treatment
Unfortunately, there is no good treatment to eliminate root knot nematodes, so the best management for plum tree nematodes is prevention. There are rootstocks that can guard against infestations, so look for plum trees that have those rootstocks and that are certified pest- and disease-free.
You can also have your soil tested for nematodes before planting, especially if there was an orchard there previously. Nematodes tend to build up in the soil and persist.
If root knot nematode is found, you can plant elsewhere or use nematicides to treat the soil. The treatment process is long and requires a lot of work, so an easier solution is to rotate in plants that are not susceptible and are not hosts to the nematodes.