Saving Citrus Trees by Removing Unloved Citrus Trees
In California our citrus trees are severely threatened by a deadly and incurable plant disease called huanglongbing or HLB. It is possible to save citrus trees from this disease by removing and destroying unloved citrus trees. Update: The free citrus tree removal program has ended.
Saving Citrus Trees by Removing Unloved Citrus Trees – YouTube Video
Huanglongbing a Significant Threat for California Citrus Trees
HLB is caused by a bacterium that is spread by an insect called Asian citrus psyllid and also by people who graft with infected budwood. A female psyllid with the bacteria in her body infects a citrus tree when feeding on it. After she lays eggs, the hatched psyllid nymphs feed on the infected tree and take up the bacteria into their bodies. As adults they fly off to infect other trees. The Asian citrus psyllid is now widespread in California and HLB has been detected in a number of areas in the state.
Proper management of citrus trees is needed to avoid infestation by disease-spreading insects such as the Asian citrus psyllid. Citrus trees that are not cared for properly can harbor Asian citrus psyllids and are at higher risk for becoming infected with HLB. Once a tree is infected the disease can quickly spread to other trees by the Asian citrus psyllid.
Removing Unloved Citrus Trees to Save Citrus Trees that we Love
On a recent visit to Disneyland, my family rented a house in the HLB quarantine zone. The house had a neglected navel orange tree. Improper pruning left fruit out of reach of people and the tree was clearly no longer valued. Preemptive removal of uncared for trees such as this one can slow the spread of HLB because the tree might be harboring HLB disease. Getting it out of the system will help to save the citrus trees that we love.
California citrus farmers used to sponsor a program that allowed people in the HLB-affected areas of Southern California to have their citrus trees removed for free.
High Level of Care Now Required for California Citrus Trees
Now that the Asian citrus psyllid and HLB are present in California, a higher level of care is required for citrus trees to prevent spread of this deadly disease. At a minimum, ants must be kept off of citrus trees as I show in the following video because they protect the psyllids from natural enemies.
Green waste from citrus trees must also be handled properly to avoid spreading psyllids as I show in the following video.
Moving Citrus Trees and Fruit Can Spread Huanglongbing Disease
Nursery citrus trees must be purchased locally and kept within quarantines to avoid spreading psyllids or HLB. Fruit must be washed and stems and leaves must be removed to prevent psyllids from riding on it.
Another common example of citrus trees that are good candidates for removal are trees whose rootstock has taken over. Such trees only produce inedible fruit and the original variety is no longer present. If your tree produces inedible fruit as this one does, you can help by having it removed.
Resources for Californians
Please visit CaliforniaCitrusThreat.org for more information on how to stop the spread of deadly citrus disease.
Funding
This article was funded by a grant from California’s Citrus Research Board.
