Good news about oak wilt in Oak Parke!  Yes, we have it; the good news is that it is contained, although we will need to be vigilant.  Here is useful information given to us by the city arborist, Chris Stolen, who came today to meet with several neighbors on Malone Drive.

The two dead trees on Brodie near Slaughter had oak wilt; it is on city property.   Mr. Stollen reports that live oaks with oak wilt need to be left standing as long as some life is in them, rather than being taken out.  That is because the way oak wilt is spread.  Live oaks have massive root systems that often can spread 50-100 feet or more, and they are connected to the native oaks around them. The oak wilt is composed of fungal spores that clog the water conduits in trees; this is what causes the “wilt.”  (Fungicide is what keeps the conduits open, and that is why it serves as inoculation for healthy trees against oak wilt).  If you dig up a dead live oak while there is still some moisture in the tree, the fungal spores that are not going up into the standing tree now are left to spread through the extensive root system into connected trees.  Therefore the tree must be completely dead before being removed.   With live oaks, the roots are connected to trees within 100-150 feet.  If your trees are further than that from a sick live oak, you probably don’t have to worry about injecting your trees.  If your trees are within that 100-150 feet radius, it’s a good idea to inject your trees as recommended.

This is not the case, however, for red oaks with oak wilt.  Red oaks with oak wilt have a fungal mat under the bark (you cannot usually see this without peeling off the bark).  What you will see is very quick death of the leaves, over as little as a two week period.  Because there is a developing fungal mat under the bark, this is where bugs come in.   If a bug is in the fungal mat of a sick red oak and smells fresh wood (from pruning without sealing) a block away, it will carry the disease quickly to another red oak.  Thus, red oaks must be removed immediately, although only by certified arborists who know how to contain the disease.   Because of the necessity of rapid removal to prevent further infection, homeowners are reimbursed by the state 40% of the cost of tree removal to encourage rapid removal.   You can get information about this through the web site, www.texasoakwilt.org.

OAK PARKE NEIGHBORS THAT ARE IMMEDIATELY IN DANGER:
Oak wilt was confirmed at 3512 Malone Drive.  The arborist recommends that the neighbors on either side of this home with oak trees within 100-150 feet, inoculate their live oaks now.  Of particular danger are those residing at 3505, 3517 and 3521 Malone Drive.   The neighbors who live in the small semi-circular section bounded by Steamboat, Malone and Sawmill will probably not have a problem for these reasons:

1. there are very few live oaks in this section
2. the live oaks that are there are further than 150 feet away from the sick tree
3. there is the street (Malone/Sawmill connection) between the sick tree and other trees that are some distance away.  That means that a trench was dug in the ground prior to laying the street down that probably severed some of the root system that might have carried the disease to neighboring trees. 

WHAT YOU CAN DO FOR PREVENTION:

Chris told us that many trees in this terrible heat are not suffering from oak wilt.  Rather, they are suffering from bacteria leaf scorch, stress from drought, or from squirrels.  Squirrels eat away the bark, trying to get water.  So don’t panic if you see tree stress.  Here’s what you can do:

1. Water your trees more often.  Those of us with sprinkler systems fool ourselves  into thinking we are watering often enough.  All of us need to take hoses and water trees by hand to help them out.
2. Educate yourself about what oak wilt looks like.  Go to the web site, www.texasoakwilt.org and look at the photos.  Live oak wilt has characteristic red veins. 
3. Oaks should not be pruned from February through June.  Regardless of season, all pruning cuts or other wounds should be immediately treated with wound or latex paint to prevent disease and insect damage.  The web site has a list of certified arborists who are qualified to prune and seal trees.  Beware of tree companies who offer to prune your trees at a very discounted price, and/or do not have a certified arborist on staff.
4. Plant trees resistant or immune to oak wilt and that are adapted to central Texas.  A comprehensive list of these trees are on the web site  Oaks that are recommended include Bur, Chinquapin and Lacey oaks.

Here’s to many more years of enjoying our beautiful oak trees! 

Warmly,

Pam Monday