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.


Scientific Name

[Fungus] Diaporthe citri F.A. Wolf (syn. D. medusaea Nitschke)

Anamorph Phomopsis citri H. Fawc Non (Sacc.) Traverso and Spessa

Other common names 

Star melanose, mudcake melanose

Disease cycle 

Melanose is a saprophyte that completes its lifecycle on dead twigs. The disease severity is determined by the amount of inoculum on dead wood in the tree canopy and the duration of wetting periods following rainfall or overhead sprinkler irrigation. Around 18-24 hours of wetting are required for infection to occur and severe infection is favored by long periods of continuous wetting. Spores cause problems when there are significant amounts of dead wood on trees, on the ground or in piles of brush left in the grove.






Leaf - about one week after infection foliar symptoms appear as small brown discrete spots. These spots become impregnated with a reddish-brown gum and are raised above the leaf surface. Early pustules on leaves are surrounded by a yellow halo. However, this halo quickly disappears leaving only small corky pustules. The numerous small pustules give the leaf a rough sandpaper texture. Distortion and dieback of young shoots are associated with severe infections.

Fruit - fruit symptoms can vary depending on the age of the fruit at the time of infection. Early infections, soon petal fall, will show relatively large pustules and when in large numbers they may coalesce to form extensive areas that often crack to produce a pattern described as "mudcake melanose". Infections during later stages of fruit development produces small discrete pustules distributed by spore-laden rain or dew which flows over the fruit surface creating the "tear-stain melanose" pattern. These injuries to the fruit rind are superficial and are not important if the crop is processed. If copper fungicides are applied for control, stippling, copper fungicide damage, may occur, which can resemble the disease and is often called star melanose.

Host range 

All citrus cultivars.


Present in most citrus producing counties.

I hope you found this page about Mal secco 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.