Kretzschmaria...death sentence...?


New Member
Hi Arbor folks,
I am caring for several large European Beech trees. One is a fernleaf variety and the other is a cultivar of F. sylvatica 'Purple Rivers'. Both trees have a DBH of over 6 ft and heights over 100 ft. At the base of one of these enormous trees kretzschmaria deusta has been detected and verified via pathology lab. I have been researching treatments to slow the progression of this decay fungus and would love some input if you have experience dealing with a similar situation.

Treatment Strategy 1
Using trichoderma spp. for biological treatment of k. deutsa (and other pathogenic fungi). As i understand it the trichoderma acts as a mycoparasite and also posesses antibiotic properties which (in a nutshell) stops the pathogens progress. After this initial benefit the trichoderma then out-competes the pathogen eventually overtaking its niche and inoculating surrounding soil to perpetuate this relationship. A product I am considering is RootShield® Plus – WP which contains Trichoderma harzianum Rifai strain T-22 & Trichoderma virens G-41. Is this treatment is worth trying or does someone have any other recommendations?

Treatment Strategy 2
Apply broad spectrum fgungicide
Agri-Fos (a Mono – and di- potassium salts of phosphorous acid based fungicide) can be effective when mixed with a bark penetrant such as Pentra-Bark®. Again, any expertise you folks could share on the subject would be greatly appreciated.

Thank you!
byacke aka Happy Valley Lorax


Well-Known Member
Perhaps start with the phosphite and then follow up with the trichoderma later? Worth a shot?

Just found a 6' sycamore with the same problem too.


Well-Known Member
I would also want to see the infection sites to see if any cultural or mechanical practices may help in those areas.
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Well-Known Member
Heres a 6-7' sycamore with probable Kretzschmaria. Note the rotting stump of a hackberry that I just cut a good sized sprout out of. Looks like a well-meaning person cut the original tree out and hit the sycamore which provided an entry point for decay.

Going to clean up this area and hit with a phosphite. What the Hell, right?