need help - maple chlorotic leaves, epsom salt concentration?

[Deleted member 21616]

I read the Montreal 2012 water analysis

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 reassurance

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 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)

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

 

[LanceMac10]

sango I've had for 6-8 years or something. I'm going to reply soon, doing laundry!!!

 

[LanceMac10]

Ha....my advice might not be as solid as folks you listed me with, but I do have a lot of JM's....

I wouldn't worry too much, I don't tend to worry about ph and chem stuff. Messing around with a bunch of stuff can lead to confused results....you know, "what actually did what, 'cuz I did everything"!


Looks like a real "sticky" mix. Doesn't seem like you'll have good oxygen transfer relative to how much water the mix holds and how much you actually add during each watering.


pine bark seeds...

 

[Deleted member 21616]

@LanceMac10 thank you!

Looks like a real "sticky" mix

can i ask what you have your potted maples in? I don't have the experience or knowledge to doubt what vineland uses quite successfully, but I would gladly improve upon it or test a few maples in other mixes! we bonsai people tend to understand the water : oxygen thing a little more, or at least pay more attention to it, than a lot of landscape people -- and there's "always room for improvement" but also "don't fix what isn't broken" LOLOL

 

[LanceMac10]

I'm moving back to turface, gravel, bark and some peat fines, I think. Pre-packaged Bonsai West mix. I've talked to some people that have used it and didn't like it. Said stayed too wet. I find it works pretty good for JM's and Hornbeams as well. I pretty much have most stuff in full sun, so the added bit of moisture retention has served me well. Or at least ok. High summer hands out a beating!!

orange dream....

 

[Deleted member 21616]

High summer hands out a beating!!

this must be why are all your trees are wet with tears in the photos?

LOL jokes aside, thanks for the info Lance

 

[LanceMac10]

sweat, most likely, they know what's coming!!

I've used lava,aka and pumice, and probably continue that with stuff in smaller containers. Mix needs LOTS of watering if you have lots of foliage/gets warm...

Mix on your coral bark just needs less watering from you. Nursery ain't looking to spend a bundle watering trees every day.....that's a lot of money. So you shouldn't water too much and site it right out in the sun!

 

[Deleted member 21616]

@0soyoung @Bonsai Nut @River's Edge @LanceMac10 @Leo in N E Illinois @AlainK

guys i ran a test with a few cultivars. For each cultivar, I used 2 'test trees', and had many control subjects from the same parent trees, of the same size, age, substrate, sun exposure, wind, etc. All trees started out healthy and free of any symptoms.

As discussed above, my issue was exclusive to kashima, kiyo hime, and (very slightly) sango kaku. I tested these 3 cultivars, as well as deshojo, katsura, hogyoku, and yves' select

--the test trees were 'over-watered'
--the control group received my usual watering

--within one week, the over-watered specimens of all 7 cultivars developed the issue we had been discussing here (see some photos taken this weekend - my phone was full but i'll take pics of the other test trees tonight). new leaves emerged very 'cholorotic', and mature leaves developed some 'chlorosis'.
--the control group remained symptom-free

the conclusion is that over over-watering was the cause, but it isn't so straightforward because only the kashima and kiyo hime (the dwarves) were really affected. the affected specimens were in the same pot size and substrate, and exposed to the same conditions (light, wind, water, etc.) as many other trees. Therefore, it possible that I was 'over watering' all of my trees and that all cultivars were more immune to the abuse than kashima and kiyo hime, OR it is possible--and I think this is more likely given the success of my other trees--that kashima and kiyo hime must simply prefer less moisture in their substrate... @River's Edge I think you pretty much nailed the dwarf-specific troubles in post #4 above, which took 2 months for me to figure out on my own Thank you!

My lack of experience is on full display here!

I just wanted to thank everyone for sharing advice, experience, and knowledge with me, which offered as much--and much needed--psychological support as help with the trees! Thank you!

 

[0soyoung]

Good job.
And an enlightening conclusion that this apparently happens because the roots are not getting enough oxygen (root anoxia).

But, I am very unclear about your 'over watering' was. It is possibly an important detail for anyone to reproduce your results (aka see for themselves).

 

[Deleted member 21616]

@0soyoung thank you and good point! here are some details:

I normally water all my trees by hand around 6am before heading to work. I normally only water one time per day (on the hottest days of the year, I leave work early and lightly re-water around 1-2pm).

I live 9 minutes from work, so for a week i went home to give a full re-watering to these 14 trees at 11am, around 1-2pm, and again around 5-6pm. At sundown, i lightly re-watered one more time.

I basically made sure these 14 test-trees were always 'just watered' and stayed dripping wet during the night, as opposed to the control group which was watered once and allowed to dry out during the day, afternoon, and night like usual

not quite scientific, but i'm happy that i solved this beyond doubt - what a relief!!! The trouble with keeping only 1 species of bonsai is that if something hits one of them there is an immediate worry that it could hit them all i have to say i'm REALLY happy that it's not my water quality! I don't know what I would have done!

 

[0soyoung]

not quite scientific, but i'm happy that i solved this

Paired comparisons are scientific tests. You had an hypothesis. You executed a test of that hypothesis. You've described your material, your methods, and your results in sufficient detail that anyone can attempt to reproduce your results. The result is not one particular/peculiar instance. IMHO, that is the gist of the scientific method.

 

[Bonsai Nut]

Do you know your water pH?

 

[Deleted member 21616]

Do you know your water pH?

nope! well, i trust the data that @Cosmos posted above, although i don’t understand water chemistry or how it affect plants in any significant detail

i was doubtful that it could be the water though, because only 2 maple trees out of many were affected, and i know many ppl who use the same water as i do

the fact that only kashima and kiyo hime are affected doesn’t appear to be a PH related issue either, because the symptoms went away for my control kashimas and kiyo himes that were appropriately watered (less than i had been watering in the past)