Question

Back of leaf  

Brown tips   Hello,

I have an avocado tree, and for the past year the tips has been turning brown, and would shed all the leaves.  New leaves sprout, but now I'm noticing brown spot on the leaves.  On the back has white flakiness along the stem and veins.

Please help! Is this a tree disease? Fungi? Mites??

Answer
Christina:

If most of the leaves on the tree have developed brown tips, I would be suspicious of a root/soil dysfunction.  This may include moisture fluctuations (too much or not enough) in the soil or a possible nutrient imbalance.  (I am assuming this tree is well established in your landscape rather than a new plant). Your closeup image of the leaf was fuzzy, so I am not sure.  Consider carry a few of these leaves to your local nursery for their comments.  There may be an insect on the undersurface that results in the flakiness.  They should have a hand lens to see up close on the leaves.  Also, look the trunk over for any evidence of bark damage and look the area over under the tree for any evidence of digging or root disturbances.  In many cases your local nursery should be able to examine your leaves for any insects.  I don't think we are dealing with a disease here but a possible insect or environmental stress. If your plant is in a pot, the roots may be too compact in the container.  This can create an unfavorable condition called root bound roots.

Regards
Steve