Citrus Arborist b 480-969-8808 Warner has been treating sick trees in Mesa AZ. for over 50 years. If you look to the left there are links to our other web sites. There is also a link to our YouTube channel. So if you live in Mesa AZ. or the surrounding areas give us a call. Thanks..


Tree service for Citrus tree diseases in Mesa Az.

Citrus scab

Scientific Name

[Fungus] Elsinoe fawcettii Bitancourt and Jenk.

Anamorph Sphaceloma fawcettii Jenk.

Other common names 

Sour orange scab




Disease cycle 

Conidia are produced on the surface of scab pustules. These spores spread to new susceptible tissue. There are two kinds of spores, clear oval shaped and colored spindle shaped (found in Florida and Brazil). The clear oval shaped type are spread by splashing rain and perish as soon as they dry, while the spindle-shaped form remain viable for a short time and are dispersed by wind for short distances.


Leaf and fruit - early scab pustules are a mixture of fungal and host tissue. These pustules are slightly raised and pink to light brown in color. Young foliar lesions superficially resemble young citrus canker and may have a slight water soaked margin. As fruit and leaf pustules develop, the small elevated pink spots become more defined and may form conical depressions nearby. As the pustules mature, they become warty and crack. Pustule color may progress to yellowish brown and eventually to a dirty grey. On lemons, tangerines, and sour orange, the growths are relatively raised. In contrast, on grapefruit the growths are flatter.

Host range 

Citrus scab is only a serious problem on some varieties. It is severe on rootstock seedlings of rough lemon, sour orange, Rangpur lime, and Carrizo citrange, and scions of Murcott tangor, Temple tangor, and other tangerine hybrids. It is occasionally found on grapefruit.


Present in most humid citrus producing areas.

Easily confused with 

Young citrus canker

I hope you found this page about Citrus scab useful. If you have any questions about Tree Disease please contact our Tree Service to schedule an appointment. We have been treating sick trees for over 50 years. We currently serve, Mesa AZ, Gilbert AZ, Chandler AZ, Scottsdale, Phoenix AZ and all of Maricopa County AZ.

We currently serve - Mesa Az. – Gilbert Az. - Tempe Az. - Chandler Az. - Queen Creek Az. - Scottsdale Az. – Paradise Valley Az. - East Phoenix Az.