Insects to blame for problems with almonds
There are eight spaces left in my master food preserver class being held all day May 26 and 27. This will probably be the last class of the season. You will be taught how to safely can, freeze, dry and preserve food for home consumption following U.S. Department of Agriculture recommendations.
The course is being taught by faculty from Utah State University at our Lifelong Learning Center, 8050 Paradise Road. For more information, contact me at morrisr@unce.unr.edu or 702-630-5173. There is a fee for this class.
Q: I'm having an awful time with my almond trees. I have two and they are about 8 years old. Last year, my tree had large almonds and was just covered with nuts. I lost all of them. The almonds have a see-through something coming out of them and when they open, they have a yellowish design inside. Then they drop. So far this year I applied Volck Oil Spray when they were dormant and two weeks ago I applied a fungicide.
A: Thanks for your pictures. Several people have visited with me about the same problem.
The squiggly resin coming from the nuts is usually a sign of feeding damage by insects with mouthparts that look like a hypodermic needle. They stick this needle into the skin of the nut or fruit and feed on the sap . When they withdraw the needle, it leaves a hole in the skin and sap comes out and dries in the squiggly clear resin that you see.
Sometimes the feeding damage by these insects can cause the nut or kernel not to form. This results in husks with no nut and the almond yellows and falls from the tree. If this happens to a few nuts and hundreds still remain on the tree, then it's no big deal. But if this happens to hundreds of nuts, then this is a big deal.
One of the culprits is the leaf footed plant bug or one of its relatives and you should keep an eye out for this pest. It is a bad one.
Another possibility could be a lack of pollination due to low temperatures during flowering or a lack of good fruit set. We did have some late freezes and if the flowers were open during freezing temperatures, it might be possible they were damaged and you lost some of your crop.
I do not believe you needed a fungicide spray. Since this happened to you two years in a row, my strongest hunch is an insect problem.
Q: We moved into our home in 2006. It was new construction and the landscaping was new when we moved in. The landscaper staked the mesquite and ash trees. Has enough time passed that it is appropriate to remove the tree stakes now?
A: If staking is done correctly, then one season of growth will be long enough to establish the tree's roots so that it will no longer require staking. Remove the stakes after the first year of growth.
Never select trees that require staking because their trunks will not support their canopies. Staking a weak trunk to support a canopy that is too large will only result in a tree that may never be able to support itself.
Q: Is it too late to apply dormant spray to fruiting plums? My tree just started blooming two days ago. I don't want to harm the good bugs.
A: Wait until after it finishes blooming to make your applications. I have made applications early in the morning with no damage to fruit trees. Dormant oils, unfortunately, do not discriminate against good or bad bugs. They suffocate them all.
Bob Morris is an associate professor with the University of Nevada Cooperative Extension. Direct gardening questions to the master gardener hot line at 257-5555 or contact Morris by email at morrisr@unce.unr.edu.
