Citrus has a long history in California. From their introduction by the Spanish in the Mission groves to the ubiquitous backyard trees of Southern California, citrus and California are interconnected the way that few places and plants are.
Now our citrus paradise is under a threat of historic proportions. Two weeks ago Huanglongbing (HLB) was discovered in a backyard in Hacienda Heights.
HLB--Yellow Dragon Disease--is known in the West as Citrus Greening and is a bacterial disease with no known cure. Its vector is the Asian psyllid, an aphid sized citrus pest that can transmit the disease from tree to tree. HLB was first discovered in Southeast Asia in the early 20th century and has been slowly devastating the citrus growing world.
California was the last citrus growing region on earth without the disease. For a while, it was thought that our climate was too dry to support the psyllid and HLB. However, the insect was found in 2008 in San Diego county and on March 30 the disease was found in Hacienda Heights.
While the psyllid is pretty easy to identify, the early symptoms of the disease are a bit trickier as they appear very similar to the symptoms of a nitrogen deficiency, with mottled yellowing of the green leaves. As the disease progresses, the symptoms are easier to recognize with dried up, bitter, and misshapen fruit. The final stages of the disease are always the same. Death.
Backyard gardeners are the last line of defense against this threat. I urge you strongly to check your trees for the psyllid or signs of the disease and contact the California Department of Agriculture (1-800-491-1899) immediately if you notice anything.
You should know that if your tree is found to have HLB, it will be destroyed. Should your tree be infested with psyllids, your tree and a 500 yard radius around it will be sprayed with chemical pesticides to destroy any psyllids.
This is an act that I am usually totally against, and one that I don't take lightly as I can remember the spraying of malathion over the city during the med-fly scare.
Yet while the consequences of reporting an infested tree are severe, the consequences of doing nothing are unthinkable. The devastation to California's citrus industry would be widespread and would come at a terrible time for the state's economy.
Yet, this is not just a threat for the citrus industry, but also for the countless families that keep citrus trees in their backyards. Citrus are some of the easiest and most rewarding fruit trees to tend and there is nothing like a sun ripened orange picked from your tree.
My great grandmother understood this when she planted a navel orange in her yard in Lincoln Heights in the 1930's. We still get a crop from that tree every winter and we also get fruit from the trees my children helped plant in our own yard a some years back. Growing citrus is one of the great priveleges of living in Southern California, a privilege that I hope will endure for generations to come. Please help. Please check your trees.
California Department of Agriculture 1-800-491-1899
California Citrus Threat Website www.californiacitrusthreat.org