Plant Answers

LIVE OAK TREE PROBLEMS AND SOLUTIONS

Hysterics of Many Texans' at this time of the year: "Help!!! My Live Oak is looking like a Dead Oak. It is completely "naked" and has no leaves-it is usually evergreen all year long. The limbs are being killed by moss and there are scabby sections on the bark. There were millions of worms eating it last spring and summer and I want to keep them off of the tree this year so they won't cause the Oak to have Decline and eventually Wilt. There are little "balls" on the bottom of some of the leaves which have fallen off of the tree. If I increase the soil micro-organisms in and on the root system of the tree by adding compost tea, molasses, Quaker Oats, soil activator, root simulator and fauna-flora motivator, will this solve my problems? If so, what amounts should I use of each and when should it be applied?"....signed: Anxiously awaiting and Desperately needing your assistance.

Lord, Have Mercy!!!! Settle down, folks! These Live Oaks have been living through all of these problems for hundreds of years before we got here and I imagine they will be doing the same for hundreds of years after we have gone. See: http://www.plantanswers.com/garden_column/jan05/3.htm
Let us take these dilemmas one at a time and see if we can console the populous. The first worry about the lack of modesty being displayed by our naked trees -they were "disrobed" by the worst onslaught of insects and diseases in 2004 we have experienced in years. Every oak tree type (Burr, Texas Red, Shumardii, Live, Monterrey) was affected by a multitude of diseases such as powdery mildew, leaf spot fungus and leaf rust. The wet, cloudy weather last summer was ideal for these diseases. Some live oaks were defoliated as a result of the insects and diseases but they will not be permanently damaged. No treatment was necessary or effective, i.e., changing weather patterns solved the disease problem naturally and the insect population went on their merry way after they completed their foliage-eating larval stage. There is nothing that can be done to avoid these naturally occurring problems except plant the recommendedtrees and shrubs for this area which can survive these environmental adversities. The never-changing list of these recommended plants are at: http://aggiehorticulture.tamu.edu/plantanswers/publications/southcnt.html The limbs are being killed by moss-nope!! The ball moss is just "hanging on" for the ride. There are scabby sections on the bark -- it sounds to me as if you are not "lichen" the way your tree's bark is looking! Ball moss, Spanish moss, lichens and mistletoe are commonly found growing on shade trees in Texas. Of these, only mistletoe is classed as a parasitic plant on ornamental shade trees. Lichens, ball moss, and Spanish moss, although found on trees, are not feeding on the tree, but only using the tree for support. For more information and control measures, see: http://www.plantanswers.com/garden_column/mar03/3.htm Concerning your fallen leaves with balls-these "balls" are galls. Gall formations have been observed in this area on red oak (cottony gall and apple gall), live oak (gouty oak gall), hackberry (nipple gall), pecan (phylloxera) and live oak (red "berry galls" on the bottom side of leaves). We might as well "enjoy" them. Spraying after you see galls won't make them disappear. They're part of the leaf, not the insect that causes them. Preventive spraying, repeated several times earlier in the year, possibly could have reduced the population of these tiny, wasp-like insects that cause this growth. Despite their undesirable appearance, they don't kill or even maim trees. See: http://www.plantanswers.com/oak_leaf_gall.htm

Nothing will cause the Oak to have Decline and eventually Wilt except contamination with the Oak Wilt disease as outlined at: http://www.plantanswers.com/calvin/OakWilt.htm

Oak species in the white oak group of the Quercus genus are "resistant" to oak wilt. Resistant means that fewer plants are affected, spread of the disease is slower, and/or that symptoms are less severe compared to "susceptible" species. However, "resistant" is good enough in most cases with this disease. Use of the word "immunity" (meaning no disease under any circumstance) is incorrect because all oaks can be killed if inoculated at a wound site with a laboratory culture of the oak wilt fungus. Resistant "white oak group" species that do well in this area include Chinquapin and Lacey.

If I increase the soil micro-organisms in and on the root system of the tree by adding compost tea, molasses, Quaker Oats, soil activator, root simulator and fauna-flora motivator, will this solve my problems? If so, what amounts should I use of each and when should it
be applied?".

The first person who can find an effective cure or prevention for Oak Wilt will become instantly wealthy (unless they are a state employee!!) and forever have the gratitude of all Texans. The Horticulture, Forestry and Plant Pathology Departments at Texas A&M University have been working for 30 years trying to find some answers to solve the Oak Wilt problem. Some advances have been made but there is still a long way to go. When you hear someone on the media indicating they have the cure for Oak Wilt in the form of soil additives, you should be wary of ANY advice given by such a person. All such curative formulas have been investigated and found to be bogus. Granted, improving a contaminated plant's growing conditions may slightly increase the plant's life expectancy but eventually the Oak Wilt claims the infected plant. Improvement in environmental conditions on a large scale (such as some rainy years) of infected trees growing in shallow soils will increase the appearance of declining trees. However, the massiveness of an old tree's root system see: http://www.plantanswers.com/garden_column/sep04/4.htm makes it difficult for compost tea and corn meal to do much good unless applied with a tanker truck for the compost tea and a dump truck for the corn meal to each infected tree.

So remember, these large oaks were here when we got here andthey will be here when we are all dead and gone. You a noticing all of these abnormalities because the leaves are off the trees at this time of the year. The leaves fall off every year at this time but because of a combination of the aforementioned problems, there are less to fall off. Ignore the "naked trees" and soon the flush of green foliage will mask all of the seemingly insurmountable, devastating problems.