yds,

Some questions about the plant. Has it been in this same pot for years? What is your watering and fertilizing regimine? Has there been an increase of rain frequency lately? Does the soil drain well? Aloha

Well I changed the pot maybe 3 years ago, and it seemed very healthy and green. I water this tree about once a week. I use liquid fertilizer every other week in substitute of water. There has not been any increase in rain lately, this tree has seen much heavier rain a year ago. Soil water drainage should not be an issue, the pot has sufficient and effective drainage.

I'm pretty sure it is infected, if this is the case, would spraying fungicide help?

yds,

Give it a try. I use a systemic Insect and disease called "2 N 1 Systemic" by Ferti-lome. Active ingredient is Tebuconazole: Alpha [2-(4-chlorophenyl)-]H-1, 2, 4-triazole-1 ethyl at 0.80% and Imidachloprid at 0.15%. Labeled for Roses, Iris, Azaleas Rhododendrons and more. I use it on all my potted plants and has not harmed any and improved some plants that I could not figure out what was the problem and some I did. I am sure there many alternatives to this product. JMHO Aloha