UACES Facebook White Oak

White Oak

December 2014

QuestionCan you please tell me what cause the white oak trees to be scaly looking and their leafs sickly looking?  Also, we have 5 white oaks on our property that were invaded by something... we thought aphids; which caused snow-like particles and also sticky residue to cover everything near the trees.  The trees look sickly. They have dropped their leaves and billions of acorns. What gives?

 

AnswerMy guess would be aphids—but maybe some spider mites too. The sticky residue you mention is honeydew droppings from the aphids.  White wooly aphids can also look almost like snow falling.  The sticky substance can cover car windshields, patio furniture and even plants beneath the tree.  If left for long, a black sooty mold forms on the honeydew.  Aphids suck sap out of the leaves and spider mites also withdraw fluids and leave a chlorotic looking leaf.  I would not be concerned with either problem as long as it happens late in the season.  If you had damage very early, this could impact the overall health of the tree if it happened year after year. Late in the season, the leaves have pretty much completed their job and the trees health will not be impacted.  Since they have good acorn production, it sounds like they are healthy.  Dry weather late in the season tends to incur larger populations as rain can often clear the insects off the leaves. 


 

November 2012

QuestionYesterday I was visiting a friend and noticed that all the oak leaves in her driveway were upside down. Today I noticed that my own driveway was full of upside down oak leaves. Interestingly not one of them was right side up. They have the lobular kind of leaves...maybe white oaks...not pin oaks. I am sure it has to do with the concave topside of the leaf and wind currents. I think it is kind of fascinating. What say you?

AnswerYou made me curious, so I went and looked at the millions of leaves in my yard, and I have a combination of up and down. I have never heard of the phenomenon before, but it is interesting.


December 2011

QuestionI am wondering if there is some scientific explanation for the huge increase this year in the amount of acorns that have descended upon our yard? We live in Bismarck, south of Hot Springs. I've been here since 1995 and of course rake the leaves and clean the gutters, and I can't recall ever having had so many acorns in the gutters and on the ground. I think they may have run their course, as far as falling, and there are still plenty is piles around the yard to dispose of. There were times a month or so ago when they fell in such volume and sound that the family thought it was a hailstorm!

AnswerWhite oaks produce acorns every year, while red oaks take two years to produce their crop. I think both trees have ample acorns this year. I am quite surprised at the volume, considering the two summers we just went through. I do think the size of the nuts is a bit smaller than they could be, and some dropped pre-maturely, but we do have a huge crop this season. Great for wildlife, but get ready next spring—if the acorns are viable, you will see tiny oak seedlings popping up wherever you left acorns.


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