Hello All, I am english and have moved to Spain, and of course started to plant all these exotic fruit trees that is not possible to plant outside in the UK. My lemon tree started to grow very fast, and is now at least two years old, it has flowered very well, but owing to a very bad spring (windy) most of the flowers were damaged, it has since started to flower again, but my question is, the new leaves that are now starting to sprout are being decimated with something!! it is not green/white/black fly, the new leaves look ok for a couple of days and then they start to go brown, as if they are being attacked by an unseen insect! I have attached three photos, I hope they are clear enough, if not I will take some more. By the way it is full somer here in Spain, 35 degress in the sun, every day, although this should not effect the tree, also, to you experts I have to apologise I do not know the name of the Lemon tree. Thanks in advance for any help Derek
Looks like the leaves have been attacked by leaf miners. Leaf miners only attack *NEW* leaves. They make the tree look very unsightly, but do not really do much harm. Most growers do nothing about them. - Millet
hello Millet Thanks for the reply, you have put my mind to rest, although you mention they do not do much harm to the tree, what happens to the new leave, do they recover! Thank Derek
No, they will not repair themselves and once again look normal. However, they are still able to produce carbohydrates (sugars) which are the food for the tree, and fruit. - Millet
I have a pretty bad infestation of leaf miners, and in my young trees they have severly damaged much of the new growth. I have used oil sprays with some success, but if I miss a week of spraying during a flush most of the leaves will be severly damaged. I have recently tried spinosad, a relatively non-toxic insecticide (although it is toxic to bees) and it seems to work. I try to spray just the new foilage during flushes.
Skeeter, because you are in Pensacola, a location that can get frost and an occasional freeze, be careful of using horticultural oils after the middle of July. Because oils after this date greatly reduces the trees ability to harden and resist freezes. Horticultural oil sprays also reduces the amount of sugars that the fruit will produce. The only real value to "controling" leaf miners in citrus is for esthetic reasons. - Millet
Millet, thanks for the warning on oils and their effect on potential freeze damage. I have recently swiched to the spinosad insecticide to control miners. It is hard for me to believe that the blistered and badly deformed leaves caused by the level of leaf miner infestation I have is just cosmetic. The leaves never reach full size, many are rolled almost to a needle, and often when the miners get into the very young leaves a large portion of the leaf will be dead.
