Other citrus-growing states could be eligible in the future, said USDA. Citrus greening disease causes fruit to ripen unevenly and to taste bitter. It is a bacterial disease that spreads internally inside a citrus tree and is spread tree to tree by the Asian citrus psyllid, described by a UC-Davis fact sheet as “a tiny mottled insect about the size of an aphid” that feeds on new leaf growth. There is no cure for citrus greening, which can kill a tree in five years. The disease was first discovered in the United States in 1998 and has since spread to nearly a dozen states.
In a Federal Register notice, USDA set a 30-day comment period on an environmental assessment of the proposed release of a parasitic wasp, Diaphorencyrtus aligarhensis, to attack the Asian citrus psyllid that spreads citrus greening disease.