Arbortech Austin Tree Service      (512) 940-0705 Austin Certified Arborists (TX-0189) since 1988 providing quality tree care in Austin. Austin Oak Wilt Oak wilt is a fungus that grows within the trees vascular system of certain types of oak trees.  Once inside the tree, the fungus moves through the interconnecting root system and infects the tree beside it.  Its growth clogs the system and kills the tree.  This illustration show the leaf symptoms (fish-bone pattern) of oak wilt in Live Oaks.  By injecting a pathogen specific fungicide into the tree, this intra-vascular bloom can be controlled.   Phytophthora This fungus is found in all our soils.  When the soil remains too wet for too long (usually from an over-watering sprinkler system) the organism can move into the trees vascular system and kill the tree very quickly.  This illustration shows bleeding cankers on the trees trunk, which are a telltale sign that the trees system has been invaded.  Other symptoms include browning leaves.  Phytophthora can be controlled by applying fungicides to the soil, and by a micro-injection of a pathogen specific fungicide into the trees vascular tissue.  Keeping soil moisture down is essential. We now have a new defense against this agressive disease. As of March 2005, the newly developed chemical, ArborFos, became available. This disease is spreading rapidly west of Loop 360. If you see these symptoms call us immediately. Bacterial Leaf Scorch Bacterial scorch affects Sycamore, Spanish Oak, American Elm, Mulberry, and some fruit trees.  Symptoms appear in mid-summer as yellowing and then browning of the edge of all the leaves on one branch in the upper canopy.  Symptoms are intensified by drought.  If left untreated, loss in vigor, decline, and eventual death will ensue. Control of insect vectors (insecticide spraying) slows disease spread.  Annual micro-injections of bactericides will suppress this disease.  Ash Yellows Ash yellows is a recently discovered disease that causes slow growth and decline in Ash trees.  It is caused by microbes called mycoplasmalike organisms (MLOs) which invade the trees vascular system.  They are transmitted by leafhoppers and other sucking insects.  This disease has been difficult to control.  A micro-injection of Oxytetracyclene and insect control are our only defense.