picture in lower left, looks like scale (your "blisters"), and maybe some spiraling whitefly activity.

DM

Here is a link that might be useful: citrus scale

Yup, it looks like scale to me too...you need to treat with some insecticide maybe some soap and water or a light treatment of horticultural oil (HD or Lowe's)...but please be careful when you treat it...do it after sunset or sundown (not in direct sun) or you will sunburn the leaves. Keep in the shade for a day or two after treating...

Neem is good but its very slow to work...I've actually used soap and water and manually removed them with a soft sponge..its tedious work and works if the tree is small and you have the time and energy to do it,lol...

Good luck!!

Thanks for info and advice dangermouse01 and puglvr1.The tree is n my yard so it gets full sun. I'll spray the whole tree (top and bottom of the leaves) in the later afternoon so that it won't get any sun for 12+ hours

Keith

If your tree is still small (and I am guessing it is), I would start by just wiping off as much of the scale from each leaf with a damp rag as puglvr1 mentioned. You could even use the soap & water or horticultural oil to dampen the rag, then you wouldn't have to spray. Dead scale doesn't necessarily fall off so by wiping them all off and starting with a "clean slate" you have a better visual of any new scale forming later.

DM

Thanks DM. I'll get to work this weekend. Any idea what the small white spots on the top of the leaf are? I've scratched some of them off with my nail.

My guess is the white stuff might be egg sacs?? You'll have to check them weekly and spray them with soap/water or treat it according to directions on the insecticide if you decide to use it, again making sure its not treated in the sun/heat of the day...

"Mango Scale pdf"

Thanks Puglvr1,

I carefully cleaned every leaf and now spray it biweekly with insecticidal soap and the leaves are bug-free.

Keith

You're welcome and best of luck!!