To Control Oak Wilt Disease

To understand why and when injection works, you need to understand how the Oak wilt fungus gets into and kills oaks. The fungus infects the vascular tissue, causing the vessels in the active, outer rings of xylem to become clogged (as likened to cloistral in humans). The fungus gets into an uninfected oak in one of two ways: either through roots grafted to a diseased tree, or by the bark beetles feeding in the branches or upper crown of the tree. When an oak becomes infected through root grafts, the fungus can spread very rapidly and extensively throughout the tree’s vascular transport system. Injection of currently available fungicides is not effective in protecting trees from root graft infection, or in therapeutically treating trees that have become infected through root grafts. Injection can be effective in preventing or treating infection caused by bark beetle inoculation.

When a beetle that is contaminated with oak wilt fungus spores feeds on a healthy oaks, several factors determine whether the tree will become infected by the fungus, or if infected, or die. These factors include the inoculum load and point of introduction, the aggressiveness of the pathogen, the physiology of the tree, the suitability of the environment for fungal growth (temperature, humidity, soil moisture, chemistry, time of year, etc.), and the ability of the tree to compartmentalize the infection, and the general health of the tree. Injection of fungicide into trees can be effective by either making the infection court unsuitable, or by stopping fungal growth within the tree. The former is the basis of preventive fungicide injection; the latter is the basis of therapeutic injection.

To be effective in preventing infection, a fungicide must inhibit or kill the fungus, and it must be present in adequate concentration at all potential points of infection. Even when injected at fairly high dosages, the quantity of chemical present at the points of potential introduction of the fungus is quite low. The chemical, dosage and means of application are critical to success.

The wood tissue in the trunk-flare of this transitional area seemed functionally different from stem tissue, and drill wounds in stem area closed more rapidly with less wet wood or pathogenic infections problems than wounds lower on the trunk root flare.

CHEMJET® - Oak Wilt Injection:   http://www.oakwilt.com/oakwilt_chemjet_app.html