i really appreciate you taking the time to look into this for me! Thank you so much for that, and for all your solid advice and reassuranceI read the Montreal 2012 water analysis
I don't know, but i buy it from vineland nursery, who specializes in japanese maples (400+ cultivars) and have been doing great for 30+ years with this soil. I only use it for my potter maples, and out of 20 or so potted landscape maples only 1 is affected, a tango kaku. and out of many many maples in the aforementioned bonsai mix, only 4 are affect (3 now, one seems to have fully recovered)How is the pine mulch composted? Has it been pH adjusted? Did it have FeSo4 added to it? Did it have copper added to it?
I appreciate all the detail, but for landscape and for bonsai, i use a very standard and very commonly used substrates - i'n not one to star making my own mixes