A sudden widespread decline of sugarberry trees (Celfis laevigufu) was observed in southern Louisiana during the period between the early fall of 1988 and spring of 1990. Approximately 3 million acres or 5,000 square miles of forested lands were affected by the decline. In addition, sporadic reports of sugarberry decline also were reported at numerous locations in Mississippi. Investigations into the long list of potential causal agents led to the conclusion that the most probable causes of the damage were due to an opportunistic exotic insect pest, Terrugonocephalaflava, a psyllid that caused defoliation and twig dieback, followed by a hard freeze which killed new regrowth following the insect damage. The psyllid has a very narrow host range attacking only Celtis species. Many sugarberry trees that survived the decline event now appear to be slowly recovering.
Solomon, J.D.; Wilson, A. Dan; Leininger, Theodor D.; Lester, D.G.; McCasland, C.S.; Clarke, S.; Affeltranger, C. 1997. Sugarberry Dieback and Mortality in Southern Louisiana: Cause, Impact, and Prognosis. Res. Pap. SRS-9.Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 19 p.