I have a young 3' Navel Orange tree with many new leaves but lately I've noticed some of the leaves look like they are half eaten. See pic. What insect/bug would cause that and how can I get rid of it? There aren't any caterpillers, ants nor bugs on the underside of the leaves. My wife has been spraying the leaves with deluted Dawn Dishwashing liquid without results. The tree has been planted in the ground for 10 weeks. All the original leaves have fallen or been blown off and have been replaced with many new leaves. It has blossomed twice. Any advice would be appreciated.
Looks like damage from leaf eating bees. If you also grow roses you should also see simular damage. Neat, round holes about 3/8" across may appear singly or in groups, with the damage always starting at the leaf edge. These are caused by female leaf-cutting bees, which resemble honeybees, except that they store pollen on the underside of the abdomen instead of in "pollen baskets" on the legs. They often nest in natural hollows in wood or underground cracks, and line their nests with the cut pieces as a food source for their young. - Millet
Thanks for the information. There is a hive under a shed nearby, but they are honeybees. Any hints on what I can do to prevent more damage to the leaves besides spraying soapy water on them? I don't have any rose bushes.
Millet: You helped me identify the leafcutter bees that were eating the leaves on my Navel Orange tree. I just read your reply to John (jbclem) about lengthwise curled up leaves. (See pic) After the meter said 'low moist' but the wooden dowel I use was just about dry, I noticed this yesterday and watered with a soaker hose for 2 hours. (24 gals.) I generally water this way twice a week. The water comes from a 750' well. It now averages between 95 and 105 degrees during the afternoons. The tree has been in the ground for 10 weeks. Is this enough/too much water in your opinion? This pic was taken 30 minutes ago at 3pm. (Peak heat.) The leafcutter bees seemed to have moved on but my wife is still going to mix up some liquid Garlic spray.
The number one killer of citrus trees is over watering. The best gauge you have for determining when to water is your finger. When the soil is damp the tree will not require additional irrigation. Because your tree has been in the ground for ten weeks the tree's root system has already begun to grow into the surrounding soil. Water again when the soil becomes somewhat on the dry side, but not completely dry. When watering a citrus tree it is best to keep the tree's trunk dry. Ninety five degrees F. is not a harmful temperature for citrus. However, at temperatures above 95F citrus will stop growth until the temperature once again falls below 95. The ideal temperature for maximum citrus foliage growth is 86F. Watering is an art and comes with practice. Good luck to you and your tree. I'm sure you will do fine. - Millet
As the bee is considered beneficial it seems only fair that a few leaves be sacrificed and considered payment for its work. Source: Keep Good Bugs in Your Garden.
Thanks once again, Millet, for sharing your expertise. I will let my wife read this since she worries when one leaf droops. Between the cheap moisture meter, the 1/4 X 16 inch dowel and my finger I'll figure it out sooner or later. Today's temp is 104 degrees.
I live up in Maine, so i deal with completely different problems usually. I've had a lot of trouble in the past with large grasshoppers- they seem to love citrus! Maybe this is your culprit? I used a bonide systemic on my trees, but powdering the leaves would probably work too.
Thanks for the comeback and the suggestion. We've figured out that this pest is a Leafcutting Bee. My wife is going to try some liquid Garlic spray. We get grasshoppers here too, but their like the seven year Locusts!
One should NEVER use a systemic insecticide on a citrus tree that is producing fruit, or will produce fruit within the next year. Systemic chemicals work by absorbing the poison into the plant making the entire plant poisonous, including the fruit, therefore all of the fruit that Dutchman's tree produced, or will produce for the next year, would become toxic and have to be thrown away. - Millet
My trees are still at least two years away from production, and i am using Bonide, which is non toxic to humans, and is intended for fruit/vegetables. I still would never use it on a plant that currently has fruit on it though.
squirrelmaniac I also use a systemic on my non producing trees. So far the best I have found is the Bayer products. As Millet stated do not use it on fruit producing trees.
