Subject: Oak wilt
Date: 6/1/2000 9:19 PM

Just noticed question about oak wilt in the Volente area.

It completely wiped out the oaks on the R. L. Leissner place (near the end
of Reed Drive) about 10 or 15 years ago.  I know that it was oak wilt
because I took a course in its detection and prevention (our property
adjoins the Leissner property.)  All of the oaks on the Leissner place and
on the Mack's Canyon Cove side of the Leissner place were infected and most
died, but our immediate neighbor had his infected trees injected with the
fungicide and most were saved and are now quite healthy.  There was no
trenching done and it did not spread.  Our own oaks (Live and Red) were
within 50 feet of the infected ones and I think they were saved because of
the fungicide and because we had some cedar trees between us.  We plan to
keep the cedars around the boundaries of our place.

Seeing the success of the fungicide, I don't understand why it is not more
widely used.
 

David Gavenda   
(Blue Heron Cove)

*On all oaks, immediately treat open wounds with a tree wound dressing or sealer.

* Never prune oaks in the spring. Prune after a freeze or in July through September, when fungus-carrying beetles are less prevalent.

* Do not to create wounds during planting.

* Do not rely completely on oak trees; plant other varieties. Avoid red oaks, like Spanish and blackjack oaks, that are easily infected.

* Use all oak firewood by spring as a precaution against insects, and never store it near healthy oaks. Do not use diseased wood for firewood.

Many oak varieties are resistant to oak wilt. A list is available from the City of Austin at 2525 S. Lakeshore Blvd.; or call 476-6487.

Copyright © 1999, The Austin American-Statesman

Preventing oak wilt., 08-03-1999.

Oak wilt is sweeping Central Texas, costing homeowners hundreds of thousands of dollars as trees undergo a wet-year growth spurt and roots increasingly capture a disease-causing, incurable fungus.

Live oaks and red oaks are susceptible, and experts say many homeowners know nothing about the disease, can't recognize its symptoms and are baffled about how to prevent it.

``This is an epidemic,'' said Eric Beckers of the Texas Forest Service.

The most common way to combat the disease is to sever an infected tree's root system by digging trenches at least 3 feet deep. In one Northwest Austin neighborhood, homeowners are looking at a tab of up to $100,000 to create a trenching program to stop the disease, which can spread from infected trees up to 100 feet outward each year.

Insects, particularly beetles, carry the disease from red oaks that develop a sweet-smelling fungus under the bark. Sap-feeding beetles feast on the fungus and carry it to live oaks, usually through open wounds left by pruning. From there, the fungus enters the roots and begins its highly contagious transfer from tree to tree.

There have been eight new outbreaks in Austin this year, but that number is changing ``from week to week,'' said Emsud Horozovic, an oak wilt specialist for the City of Austin.

Since 1988, the city has recorded 165 oak wilt outbreaks. That number represents only those people who called the city's foresters to ask for help, and there is no telling where the disease has gone undetected due to lack of knowledge or money to fix the problem, Horozovic said.

A city ordinance requires that dead red oaks be cut down because of the lethal fungus. However, because the disease in live oaks is spread primarily through the root system, there is no requirement to remove diseased or dead live oak trees.

Neither the city nor the Texas Forest Service office -- each with two foresters -- has the resources to randomly check neighborhoods for oak wilt. ``Our salamander is not in one pool,'' said Horozovic, who leads the city's oak wilt division.

Foresters said it is all they can do to keep responding to calls.

One day last week, Beckers traveled 130 miles in southern Travis County to visit four communities that suspected outbreaks of the disease. All four have it.

Once an outbreak is confirmed, stopping it will require that expensive trenches be dug, and damage to city streets and utilities must be repaid. Oak wilt containment is a volunteer program left up to homeowners associations and neighbors who are willing to pay for it.

Federal grant money that a year ago contributed up to $10,000 to fix the problem has dwindled to a $5,000 cap per neighborhood. The federal government does pay 50 percent of the cost for removal of red oaks.

Most oak wilt outbreaks have been reported west of Interstate 35, particularly to the southwest and west of Austin. In the Northwest Hills east of Mesa Drive, homeowners in an affected area south of Doss Elementary School are being asked to cough up $1,000 each to stop the disease from spreading.

Already, some homeowners have sunk thousands into trying to save trees by using fungicide injections. When the fungus attacks a live oak, it clogs the tree's arteries, making it impossible to receive water. The fungicide opens up the arteries, but the root system will forever carry the disease.

``I'm going to fight for mine,'' said Marcia Manor, who lives in the affected neighborhood. ``I've spent $3,200 so far.''

Manor had a professional tree service inject the fungicide, but Horozovic said the city will teach people how to do the process themselves. Still, there is no guarantee the fungicide will extend the life of infected trees.

``It's a wait and see thing,'' Manor said.

Trenches in the neighborhood must be dug 100 feet beyond the infected area

``It's to isolate the disease's spread, making a barrier between healthy trees and unhealthy trees,'' Horozovic said. Studies show trenching has a 74 percent success rate in stopping the disease from spreading.

Foresters said Central Texas newcomers often fail to take preventive measures, such as pruning trees in the hottest, driest part of the year or after a good frost in winter, and then painting over the open wounds. But even longtime Austinites often ignore the problem until it's too late, failing to recognize the symptoms of the disease -- such as leaf discoloration -- in time.

But almost everybody is surprised and angry to learn that containment measures come at a homeowner's expense, Horozovic said. The average cost of containment is generally under $10,000 for an outbreak, he said.

In the affluent Northwest Hills neighborhood, costs are higher because much of the trenching will have to be done with hand tools to minimize damage to sprinkling systems, swimming pools and expensive landscaping and fencing in the affluent area.

Most of the homeowners are longtime residents who built their homes when Austin was a small town and gravel roads wound through the area, homeowner Maxine Lain said. The majority are retirees, and some are finding the $1,000 assessment too steep, she said.

While the neighborhood is scrambling to deal with its problem, it also is looking for other residents interested in asking the city to help defray the cost of oak wilt containment.

``This is not a neighborhood issue,'' homeowner Jimmie Ann Vaughan said. ``This is a City of Austin issue and a Travis County issue. There is no infrastructure set up to save our trees.''

You may contact Kim Sue Lia Perkes at kslperkes@statesman.com or 445- 3974.

Copyright © 1999, The Austin American-Statesman

Kim Sue Lia Perkes, Oak wilt victimizes Central Texas; Disease is killing neighborhood trees; solutions are expensive, elusive., 08-03-1999.

Neighbors rebound from oak wilt losses

CASTLEWOOD/OAK VALLEY AREA

Bill Peters is one of many homeowners in the Castlewood/Oak Valley neighborhood who have lost trees to oak wilt.

To restore what was lost, he planted five trees on the City of Austin' s right of way in front of his house, with the help of the city's Cool Communities Program.

"I could spell oak wilt, but I didn't know what it was," said Peters, who lost about 10 trees to the fungus that spreads through root systems and causes the trees to wilt and die. "Because of this program, I have been able to replace half of the trees I lost a lot faster."

The Castlewood/Oak Valley area is one of four neighborhoods involved in the program, run by the Parks and Recreation Department.

Participants sign an agreement to adopt a four- to 10-foot-tall tree at no cost.

They plant the trees on the right of way between the sidewalk and the street and water them at least once a week for three years.

About 27 homeowners in the Castlewood/Oak Valley neighborhood adopted 67 trees.

Pecan, bur oak and cedar elm, which are not susceptible to oak wilt, were among the trees adopted.

"I like to call it an adoption because when a family adopts a child, that child will always be their responsibility," said Jan Fulkerson, Cool Communities coordinator.

"The same goes for the tree. That tree is a part of their family now. It's their responsibility. I'm very glad this program was able to help this community rebuild after their fight against oak wilt."

To fight the disease, the area's neighborhood association raised more than $8,000 in a door-to-door campaign in February and March to help pay for a trenching project to stop oak wilt.

In June, city crews completed the trenches in the neighborhood bordered by Manchaca Road to the east, Davis Lane to the north, Queenswood Drive and Huebinger Pass to the west and Monarch Drive to the south.

The neighborhood's trenching project was one of the biggest in the city.

Officials said the oak wilt claimed hundreds of the neighborhood's trees.

"This program is definitely a way our community can start rebuilding again after our fight with oak wilt," said tree adopter Marilyn James.

Copyright © 1994, The Austin American-Statesman

Sheryl Kennedy, Neighbors rebound from oak wilt losses., 11-04-1994.

In July, residents of McNeil Estates, a North Austin subdivision, discovered an epidemic. Majestic oaks, some 800 years old, were dying from oak wilt.

Homeowners acted quickly, meeting with city arborists, contacting Texas A&M specialists and raising money. Sixty days later, a contractor they hired began digging deep trenches, cutting through tree roots to stop the spread of the disease.

The cost was $250 per homeowner, but that represented a tremendous savings over the cost of removing dead trees, property value decreases and higher electric bills because of lost shade, said Teresa Elliott, neighborhood association president.

Elliott has advice for other neighborhoods that discover oak wilt. "Act quickly," she said. "Don't get caught up in neighborhood meetings and arguments. Oak wilt spreads incredibly fast. There isn't time to waste."

The cooler weather of fall ushers in an increased threat of the infection, said James Rooni, City of Austin forester in charge of the Oak Wilt Suppression Project.

With millions of Central Texas oaks dead and dying from oak wilt, there is a good chance that the oak firewood for sale is coming from an oak wilt area, Rooni said. Red oaks - the Spanish oaks and Blackjack oaks - are the most risky, he said.

These oaks, when dead, produce powdery mats of spores that attract insects. The burrowing bugs carry the spores to other trees. "That' s where new epidemics get started, causing widespread damage," Rooni said.

Particularly vulnerable are live oaks and red oaks with fresh wounds, either from pruning or wind damage. Bugs seek out those openings.

Once a tree is infected, it will spread its disease through its shared root system. This has resulted in thousands of dead trees in a single neighborhood, Rooni said.

The disease continues to spread.

Rooni said foresters have identified 114 pockets of oak wilt in the city.

The disease is most prevalent west of the interstate, running north and south into Oak Hill. "Wherever you find populations of oak is where you find the oak wilt," Rooni said.

* Try to avoid oak firewood. There are alternatives, including pecan, hickory and mesquite.

* If you do buy oak, make sure it's not from infected oaks or frominfected areas. (There is no way to tell whether the wood is infected just by looking at it.)

* Buy only what you will burn this winter.

* Make sure the oak is dry. Dry oak weighs less, has loose bark andusually displays a distinctive cracking pattern on the cut ends. Oak wilt cannot survive in dry wood.

* Cover oak firewood of unknown origin with heavy, clear plastic and buryall the edges to act as a barrier to insects that spread the disease spores. Keep the pile covered until all the wood is used.

* For more information, call the City Oak Wilt Hotline at 472-7606.

Copyright © 1994, The Austin American-Statesman

Pamela Ward, Quick action needed to fight oak wilt, experts say., 11-06-1994.

Over the past decade, oak wilt has been responsible for the loss of over 10,000 trees in the city of Austin. These losses not only have taken away from the aesthetic beauty and rich heritage of our city, but have caused direct losses in real estate values estimated into the millions of dollars.

What exactly is oak wilt - and what can be done about it?

Oak wilt is a vascular disease caused by the fungus Ceratocystis fagacearum. Virtually all oaks can be infected by the pathogen. Red oaks are most susceptible and white oaks least susceptible to the disease. Live oaks fall between the other oaks in vulnerability.

The disease stops the flow of nutrients and water from the roots to the leaves. Once symptoms appear, a Spanish oak may die in as little as two weeks. A live oak tree can survive longer - perhaps up to a year.

Symptoms of oak wilt can take several forms. Veinal necrosis is a widely accepted, but not foolproof, symptom on live oaks. The interveinal areas on the leaves stay green while the areas directly adjacent to the veins die. Before the brown coloring, the dying area often is bright red or orange.

Red oaks infected with the disease frequently will turn a brilliant red in early summer and lose all their leaves. On some infected Spanish oak trees, a fungal mat forms under the bark. It is this mat that attracts bark beetles, which carry the spores to open wounds on other oak trees.

The chain of infection begins when a new disease center is formed. This occurs when an oak sap-feeding beetle, which has been feeding on the sap of a red oak tree containing a fresh oak wilt fungal mat, carries the fungal spores to a new, uninfected tree. These beetles are attracted to uninfected trees by the sap from fresh wounds, and they are attracted to any wound, whether it is caused by pruning, careless lawn mowers, or an accidental cut on the oak tree.

Once the new disease center is formed, the disease spreads in two ways: by insect vectors (sap feeding beetles), and through the interconnected roots of oak trees. The latter is more common in the Austin area, where we have a large number of live oak trees.

Most live oaks have interconnecting root systems, because of their habit of root sprouting, and in some cases root grafting. Oak wilt can spread through interconnected root systems at a rate of 75 to 100 feet per year, quickly infecting and killing large clumps of live oak trees.

New disease centers are most likely to occur when the sap beetles and the oak wilt fungal mats are most prevalent and active, which is in the spring and fall. However, precautions to prevent oak wilt should be taken at all times of year.

There are a number of effective measures that can minimize the threat of oak wilt:

* Prune oaks only in deep winter or deep summer. Any wound on an oaktree when the bark beetle is active is likely to get visited by the beetle. If the wound and the visit occur during spring or fall, when the fungus is also active, there is a chance that the tree will be inoculated with the disease.

Immediately treat every oak wound with pruning paint, regardless of its size or the time of year. Paint wounds with a high quality tree wound dressing, which will not impede the tree's natural healing process. Although there is controversy over the benefits of horticultural wound dressing, its use in live and red oaks does reduce the risk of oak wilt infection. Wounds must be treated immediately; treating old wounds is not necessary because after two days, wounds are no longer attractive to beetles.

Remember that pruning is only one of the ways trees get wounded. Automobiles, lawn mowers, string trimmers, wind, ice breakage and bulldozers are other commom causes of wounds.

* Manage firewood to avoid infection. It is not necessary to avoid usingthe fireplace to stop the spread of oak wilt; smoke from infected wood burning is not a threat. The fungus is destroyed by heat and will not even survive in dry firewood.

If you use red oak firewood, try to buy wood from trees that have not been infected or killed from oak wilt. Only wood that has been cured for an entire summer should be stored near uninfected red or live oaks. If you buy oak firewood and are unsure of its age or origin, use it up before spring.

* Diversify your shade tree plantings. Large blocks of red and live oaksare susceptible to the spread of the disease. Plant Afghan pines, redbuds, cedar elm, chinkapin oak, bur oak, Chinese pistache and Monterrey cypress in addition to red and live oak.

* Prevention is best, but there is a treatment procedure for oak wiltdisease.

The Ciba-Geigy Company recently was granted a federal label for the use of Alamo fungicide on live oak and red oak trees. Previously the label only covered the treatment of live oaks.

If it becomes necessary for you to use the Alamo chemical treatment, it is probably best to rely on a reputable local arborist to do so. Alamo must be injected in a very specific manner into the base of the tree to be effective.

The Alamo chemical control program is most effective when used in combination with trenching to break up root grafts. Properly installed trenches also will reduce the number of trees that will need to be injected.

For more information concerning oak wilt disease in the city of Austin, call 476-6487 for the Oak Wilt Suppression Project office of the Austin Parks and Recreation Department. For cases outside the City of Austin, contact your local county Extension agent.

Ted Fisher is the horticulturist with the Travis County Extension Service.

Copyright © 1993, The Austin American-Statesman

Ted Fisher, Prevention best method in fight against deadly oak wilt in Austin., 10-30-1993.

The pink ribbons on the trees and the banners she has stretched across her lawn have done their job well, says West Austin resident Idee Kwak.

After all, Kwak knows that if you want somebody's attention, it doesn' t hurt to use a little flash and dazzle to get the job done.

"The ribbons? Oh, they're a trick to get my neighbors interested," she says of her front yard decor. "This is saying, `We need you, the city needs you, and your neighborhood needs you.' "

What Kwak wants from her neighbors is a commitment - and that means possibly a chunk of their yard, time, and money - to fight the oak wilt that is threatening to strip her street of the towering oaks that are so susceptible to the disease.

In the neighborhood just south of Kwak's Perry Lane home, more than 100 diseased oaks have been taken down despite spirited and expensive efforts by residents to halt the spread of the disease.

Now Kwak and her neighbors are worried their oaks will join the more than 10,000 trees in Austin that have been lost to oak wilt, a disease caused by a fungus that spreads through the trees' common root systems. Once a single tree becomes infected, the disease may spread rapidly to adjacent live oaks as the fungus travels through the interconnected root systems.

Sap-feeding beetles also have been known to carry spores from diseased red oaks or firewood to fresh wounds on healthy oak trees.

While none of the 23 oaks in Kwak's front yard has become infected with the disease yet, she found out last summer that a neighbor who lives behind her home is already fighting the disease.

"I was preparing to landscape my front yard, which was damaged from the freeze last winter," said Kwak, who is married to Sung Kwak, music director of the Austin Symphony.

"But my landscaping came to a screeching halt when I talked to my neighbor, and he said, `Are you going to landscape for sun or for shade?' " said Kwak.

Realizing that something needed to be done immediately, Kwak began to educate herself about the disease and rattle the neighborhood with warnings about the critical threat to the Perry Lane oaks. "The first thing I did was get in touch with the dear people at the city (forestry unit) for information and to find out what to do," said Kwak.

"Then I made more than 200 notes that said, `Oak Wilt has hit Perry Lane' and stuffed them in mailboxes over a large area. I put a big banner in my front yard and hung posters announcing an oak wilt meeting.

"I wanted to get the neighborhood organized to educate them and notify them that this is an ongoing fight that may end up in their yard," she said.

Kwak attracted about 70 neighbors in early August to a meeting in her home, where a city forestry expert described the disease, its ramifications, and the possible need to dig a trench to sever the roots of diseased trees from those of healthy trees. That trench, which needs to be dug a minimum of 75 feet from the nearest diseased tree, has taken time, commitment, and cooperation from her neighbors, said Kwak. But neighbors did pull together, and the trenching operation began Monday in the yards of nine homes on Perry Lane and Glen Rose Drive.

The trench, which will be 993 feet long when completed, will be about 6 inches wide and 36 inches deep. Although trenching can be expensive - ranging from $1.50 to $8 per foot - it is considered the most cost effective way to suppress oak wilt, said Carl Schattenberg, oak wilt forester in the city's Parks and Recreation Department.

Treating infected trees individually with a fungicide sold under the name Alamo can cost several hundred dollars per tree, Schattenberg said. And that treatment does not stop the spread of oak wilt. If the homeowner prefers to ignore the disease and lose his trees, it can cost $500 and up, depending on the size of the tree, to remove a dead tree from property.

"Digging a trench is the least expensive protection for your tree. If someone from your neighbohood comes to your door and says, `We' re going to dig a trench,' you should say, `Thank you for including me,' " said Kwak. "Even if you hate trees, it's less expensive to put that trench in than remove the dead tree."

However, Schattenberg said the cost is the major obstacle neighborhoods face in trying to get residents to cooperate in trenching. "A lot of people have trouble going paycheck to paycheck. And it's especially hard for them to participate if they don't have oaks on their property and they're asked to spend $500 to save their neighbors' trees," said Schattenberg.

In some cases, Austin residents can obtain partial reimbursement for expenses incurred in fighting oak wilt through the Texas Oak Wilt Suppression Project. That program, administered by the Texas Forest Service in cooperation with several entities including the USDA Forest Service, Travis County, and the city of Austin, can provide up to 50 percent of direct control costs.

And both Kwak and Schattenberg urge neighborhood groups to develop funds to assist homeowners with their costs for controlling oak wilt. "If I had a wish list, I would wish that neighborhood associations would jump in with funds immediately for home owners who need help, " said Kwak.

"It's important for neighborhoods to be educated and prepared because when oak wilt affects your neighborhood, it needs to be treated immediately, " she said.

Kwak's fervor for saving area oaks has been critical to pulling the neighborhood together to dig the possibly tree-saving trench. "The role Idee has played along Perry Lane has been that of sparkplug. She has motivated everyone. She has rallied the forces to make the neighbors take action," said Schattenberg. "And unless the homeowners take action and get involved, there's nothing I can do about it."

Kwak credits the Edgemont Live Oak Savers Association with helping her stir her own neighbors to action. The Edgemont group, which involves a neighborhood west of Camp Mabry, was formed more than two years ago to slow the spread of oak wilt in that area, said Tom Bishop, co-chair of the group's steering committee.

That group launched an education and fund-raising program that eventually generated more than $8,000 in contributions to help residents in the area fight oak wilt, said Bishop.

The Edgemont organization, along with nearby Camp Mabry, has undertaken several phases of trenching and tree removal to slow the spread of the disease, Bishop said. The Texas Forest Service has reimbursed area residents more than $9,000 for their efforts thus far, he said.

The trench going in Kwak's neighborhood, which borders the Edgemont area, is expected to "band off the northward progress of the disease, " said Bishop. "We just have got our fingers crossed. We're just trying to be optimistic. But if we don't do anything, we're going under."

Although more than 100 diseased trees have been removed from the Edgemont area, Bishop said he and his neighbors feel certain they've slowed the progress of the disease and probably prevented new infection in many cases.

"This is an ongoing thing. If our neighborhoods would just jump on it and try to control it, I think we could come to grips with urban oak wilt in Austin," he said. "So we're going to keep on keeping on."

That sort of attitude can help neighborhoods and individuals cope with the challenges of oak wilt, Schattenberg said.

* Refrain from pruning oaks from February through June and from lateSeptember through November to minimize the possibility of infection by sap-feeding beetles.

* If oak trees are cut or wounded at any time of the year, immediatelypaint all cuts - no matter what size - with a standard wound dressing. Paint each wound before making the next cut on the tree.

* When you hire anyone to prune your oaks, hire knowledgeable andreputable companies that follow oak wilt management techniques. Require that all cuts be painted and all tools be disinfected.

* Buy only very dry oak firewood. Green oak firewood can harbor the oakwilt fungal spore. Burn all oak firewood before Valentine's Day to keep sap-feeding insects from spreading the spore should the firewood be infected.

* Pruning tools should be disinfected before cutting each tree. UseLysol spray, denatured alcohol or a bleach solution (50 percent bleach and 50 percent water.)

* Educate your neighbors about oak wilt.

Copyright © 1990, The Austin American-Statesman

Cheryl Coggins Frink, Commitment against oak wilt: Idee Kwak uses flash and dazzle on neighbors to join tree disease fight., 10-04-1990.

With changing leaves and a bountiful supply of acorns on the ground, fall has certainly arrived.

Live oaks, those prodigious acorn-producers, are one of the most common tree species native to Central Texas. Many specimens can be found in Austin parks, neighborhoods and the surrounding Hill Country.

Quercus virginiana var. fusiformis has coarse, oval-shaped, evergreen leaves, two to five inches long, with occasional teeth. The bark is rough and gray-black in color. Live oak trees flower in April and are wind-pollinated - they probably contribute to many springtime allergies. The acorns, just now ripening, are an inch long, ark brown when mature, and pointed at the tip

Q. virginiana ranges from southeastern Virginia to southern Florida and Mexico. In earlier days, many U.S. Navy ships were constructed from its dense, strong, rot-resistant wood. Our local variety, fusiformis, is found in Central Texas, the Wichita Mountains in southwestern Oklahoma, and the mountains of northeastern Mexico.

The live oak is an important part of Central Texas ecology. Its abundant sweet acorns are immediately consumed or stored by wildlife. From the looks of this year's production, we can expect a bumper crop of squirrels next spring. Both ball and Spanish moss are found on live oak branches, along with various forms of insect galls common to oak species.

Live oak is rhizomatous, which means that it forms underground stems. Most of what we know about the natural history of this species is related to this trait.

For example, many biologists believe that the Hill Country was more savannah-like before 1850, when settlers began moving in. This grassland community was maintained through fires set both by Indians and lightning. As the Hill Country was settled, fenced, and grazed, these frequent fires were suppressed. Because it could sprout from its underground rhizomes, the live oak was able to regenerate more easily than Texas oak or post oak (Q. texana or Q. stellata) and was often found in "mottes," clumps of interconnected individuals. These oak mottes are still common in the Hill Country.

While this pattern of underground rhizomes and interconnected individuals helped live oaks survive in earlier times, it may be the undoing of this species in the age of oak wilt.

Oak wilt, caused by a fungus, may be spread in two ways: by a specific beetle that carries the fungal spores or through root grafts (unions of separate trees). Although the mechanism is not well-understood, the oak wilt fungus essentially plugs up the vascular system - the arteries and veins - of oak trees. A group of trees that looks like separate individuals may be sprouts from the same underground stem. When this is the case, the oak wilt fungus can spread easily through the trees. Because of the abundance of oaks in Central Texas, oak wilt is a serious disease. Imagine Austin without oak trees.

To reduce the spread of oak wilt, do not prune trees from March to July. The fungal spore-carrying beetle, which is attracted to fresh tree wounds, is active during this time of year. If a right-of-way must be cleared in your area, insist that oak trees wounded during this process be painted with a wound dressing.

When using live oaks in a landscape, be sure to start with container- grown plants. Plants grown from seed in sterile soil and planted separately will take many years to root graft.

For more information on the disease, contact the Oak Wilt Suppression Program at 476-6485.

Katy McKinney is a research botanist with the National Wildflower Research Center.
 

Copyright © 1989, The Austin American-Statesman

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