Is it clear and shiny and STICKY? :-)

Your plants probably have an infestation of either aphids or scale insect, both of which excrete a clear, sugary substance that coats the leaves as well as everything below the plant.

Take a close look.

Yes to all. I saw some white thing like very small rice on underside of leaves. What will get rid of this?
Thks karen

Pictures would be helpful. Descriptions like that aren't very helpful...your 'like rice' could mean all kinds of things.

I read an article about crepe myrtle aphids...googled it. I am sure that is what it is. Said to use bayer tree and shrub for insects...it is systemic. I got some at walmart after work and putvon tree. Also sprayed with bayer insect spray yesterday. Hope that does it. It is supposed to last one year.

I think, if you applied the systemic you would have been better served by doing a fresh water rinsing of the leaves to remove the honeydew before sooty mold set in. I am not going to even try to look up the difference in ingredients between the two products, but you may have doubled the pesticide dosage to that plant. Not a good practise on so many levels. For the health of the plant, for the environment and for your pocketbook.

Yikes! Won't do that again. Thanks for letting me know. Geez.

if you put on a systemic.. then one might suggest that your topical application was redundant.. and therefore pollution.. on some level ...

i truly believe in nuclear warfare on bad infestations.. but i dont use two bombs.. where one will work .. its just overkill ... or what i call 'too much love'

i dont mean to insult or degrade you.. just to hope that next time.. you dont get carried away ...

most aphid problems can be cut significantly with a hard spray of water ..

also the bayer tree and shrub i use.. is a soil drench.. you said you put it ON THE TREE ... hopefully just a poor choice of words.. apply all chemicals specifically according to instructions ...

as of now.. i think you fixed the problem ...

BTW .. the shiny stuff is honeydew ... that which the aphids excreted from themselves. . its sugary ... and i usually find such when i notice the army of ants that are literally.. MILKING them for such ... should you now see the ants.. they are now lacking their cows [????] .. ignore them.. they will move on ... no need for a third spraying .. if any survived the first 2 ...

ken