Work through the tree at multiple heights — not just eye level:

• Underside of leaves — flip several at different heights. Tiny brown or white bumps that don't brush off = scale insects
• Branches and new growth — run a finger along a branch. Sticky or tacky residue = honeydew from sap-sucking insects
• Base of trunk — ants marching in a column up the trunk almost always means they're farming scale insects above
• Fruit surface — small holes, soft dimpling near the stem, or streaks under the skin = fruit fly damage (very common on Oahu)

Pull leaves from three levels — outer canopy, mid-canopy, and lower branches. Healthy: dark glossy green, firm, uniform color.

• Overall yellowing (older leaves first) = nitrogen or iron deficiency — very common in Hawaii's high-pH volcanic soils
• Yellow patches, green veins still visible = iron or manganese deficiency
• Small brown spots with yellow halos = fungal infection (mango anthracnose is the most common)
• Leaves curling inward or cupping = water stress or thrips
• Heavy leaf drop outside normal flush cycles = root stress — always worth flagging

Stand directly under the tree and look straight up. A healthy canopy has scattered patches of sky visible through it. If you can't see any sky at all, it's too dense — trapped humidity accelerates fungal disease fast in Hawaii's climate.

• Crossing or rubbing branches — remove bark over time, creating infection entry points
• Water shoots — thin, fast-growing vertical branches that drain energy without producing fruit
• Heavy imbalance — one side significantly denser than the other is a structural risk

Do a slow walk-around at ground level — takes 5 minutes and catches what most homeowners miss:

• Press lightly on the bark at different heights — soft or spongy = rot inside the wood
• White or gray fuzzy patches on bark = surface fungal growth
• Amber or dark sap weeping from cracks = borer insects or bacterial canker
• Root collar (where trunk meets soil) — should be firm and uniform; darkening or soil pulling away = root rot risk
• Heaving surface roots or sunken soil near the base = root system under stress