Question
my meyer lemon tree has sap on the leaves and little brown spots..it is dying slowly what can I do?

Answer
Hi Ed,

Most likely, the small brown spots are scale insects.  They appear oval to round in shape, approx. 3 to 5 mm in diameter.  They exude a sticky sap called "honeydew".  Scale infestation is a very, very common problem, so there are many effective measures to treat them.  

If you lemon tree is small and in a container in the home, the scale insects can be removed by using a solution of soapy water.  The adult scale insects are difficult to remove from the leaves, but they can be dislodged by using an old toothbrush and the soap solution.  Solutions of rubbing alcohol can also be used to rid the plant of juvenile insects.  The juveniles are small white tufts that are motile.

If your infestation is large, there are several oils that can control the infestation.  These oils (called horticultural, summer, or Volck oils) must be used according to directions as the plant may be "burned" if application concentrations are too great.  The concentration applied is related to the ambient temperature.

Good Luck and Good Gardening.