The psyllid can carry one of the most devastating citrus diseases in the world, Huanglongbing. California residents play a critical role in protecting our state’s iconic citrus. The insect:
The Asian citrus psyllid is a small insect that feeds on the leaves and stems of citrus trees. The insect is extremely dangerous because it can transmit a disease that is fatal for citrus. The deadly bacterial disease is called Huanglongbing (HLB), also known as citrus greening disease, and it has been found in Southern California, putting all citrus trees at risk. Once a tree is infected with HLB, there is no cure and the tree will die. The best way to prevent the disease from killing citrus trees is to stop the Asian citrus psyllid.
The Asian citrus psyllid is roughly one-eighth of an inch long, about the size of an aphid, and has brown mottled wings. It feeds at a 45-degree angle, making the insect appear almost thorn-like on leaves and stems. The eggs of the Asian citrus psyllid are yellow and are often found on the newest growth, nestled in the crevices of unfolded leaves. Juveniles (nymphs) produce white, waxy tubules and also appear on new growth.
Trees should be inspected on a monthly basis and especially during periods of active plant growth or "flushing." Due to the small size of the psyllid, using a magnifying glass or hand lens will make inspection easier.
If you think you’ve found the Asian citrus psyllid, ACT FAST! Call the California Department of Food and Agriculture hotline at 1-800-491-1899, and talk to your local home and garden center for information about products that can help protect your trees.
The Asian citrus psyllid was first detected in California in 2008 and is now confirmed throughout much of the state, including Southern California, the Central Coast, the San Joaquin Valley and the Bay Area. When the pest is found, quarantines are put in place to restrict the movement of citrus plants and plant clippings in order to limit spread of the pest.
It is important to remember that it is illegal to bring citrus fruit or plant material into California from other states or countries. In California, everyone must obey the quarantines set in place and not move citrus outside your area. For the most up-to-date quarantine and restricted area information, visit the California Department of Food and Agriculture website or talk to your local agricultural commissioner’s office.
The Asian citrus psyllid can fly short distances and be carried by the wind. However, a main way the Asian citrus psyllid spreads throughout the state is by people transporting infested plants or plant material. For this reason, everyone in California is asked to not move citrus and to only purchase citrus trees from reputable, licensed nurseries in your area.
The Asian citrus psyllid feeds on all citrus trees, including orange, lemon, lime, mandarin, pomello, kumquat, grapefruit and tangerine trees. It also feeds on some relatives of citrus, like orange jasmine and curry leaves. If you have any of these plants in your backyard, inspect them monthly, or whenever watering, spraying, pruning or tending trees. If you think you've found in the Asian citrus psyllid, report it to local agriculture authorities, and talk to your local home and garden center for information about products that can help protect your trees.