Cork bark Pinus thunbergii

Potawatomi13

Imperial Masterpiece
Messages
6,173
Reaction score
4,404
Location
Eugene, OR
USDA Zone
8
Picked up two more pines. Same age as the other. From the late Dave Dewire.

One has fewer roots than the other two and no visible micorrizhae.
Great looking but for reverse taper at base🤨.
 

clem

Chumono
Messages
780
Reaction score
1,876
Location
Normandy, France
Great looking but for reverse taper at base🤨.
it is very often seen on corticosa, even on Kokufu level trees...
pin thunberg fils ecorce2 taikanten2018.jpg

Look at this video (centenary corticosa JBP in a japanese nursery) ->

On Bonsai Focus 120, there is an article (from Kinbon magasine) about corticosa JBP, and here is a pic of the classification ->
corticosa.JPG
 

Brian Van Fleet

Pretty Fly for a Bonsai Guy
Messages
13,996
Reaction score
46,166
Location
B’ham, AL
USDA Zone
8A
Mancozeb arrived today.
The recommended dilution is 2-5 tsp/gallon of water.
I’m leaning towards 2 tsp/gallon since the pines are not growing vigorously and one has a root system that is lacking. Does this dilution seem appropriate for my situation?

A plastic sheet will be laid on soil surfaces to prevent dripping into roots. Proper PPE will be worn.

I am also wondering if it is worthwhile to spray mancozeb on vigorous pines with only minor amounts of needlecast?
Just follow the instructions, middle of the road, and yes, hit anything with needle cast.
 

Bonsai Nut

Nuttier than your average Nut
Messages
12,477
Reaction score
28,122
Location
Charlotte area, North Carolina
USDA Zone
8a
A plastic sheet will be laid on soil surfaces to prevent dripping into roots. Proper PPE will be worn.
It actually won't harm the roots, however you need to protect the soil, because Mancozeb does not distinguish between harmful fungi and beneficial fungi. It will have a huge negative impact on your soil biology if it drips into the soil.

https://www.beyondpesticides.org/as...al_fungi_in_ecotoxicological_studies_Soil.pdf
 

Cruiser

Chumono
Messages
664
Reaction score
1,443
Location
Western Washington
USDA Zone
8a
Thanks for the comments, everyone.

The plan is to spray the trees asap with a dilution of 3tsp mancozeb/gallon water.

Interesting info, Clem. Two of the trees look similar to the corticosa at their bases. On the other hand, after reading some of Van Fleets articles I’m wondering if I could have a Taihei. There is a reddish hue developing in some of the fissures.
The bark on all three looks very similar. Ridges appear to be thickening more quickly in certain areas giving it a winged appearance.
One noticeable variance is that the reverse taper tree has darker and longer needles.

I suspect it will become easier to identify the varieties as the trees grow and vigor returns..
 

Cruiser

Chumono
Messages
664
Reaction score
1,443
Location
Western Washington
USDA Zone
8a
6/7:
Sprayed corkers with mancozeb. Gave the needles a thorough shower on the top and undersides. Probably 3 or 4 passes of spray for each needle cluster.

An absorbent sheet was laid on the ground to work on. Mask, gloves, nomex long sleeve shirt, and glasses were worn.

A 1 gallon pump sprayer was used.
I ended up cutting paper plates and putting them on top of the containers to catch excess drips. They worked well but a couple of drops may have made it into the soil.
 

Attachments

  • 99654D32-4C1A-4E28-BD91-AC355F642DC3.jpeg
    99654D32-4C1A-4E28-BD91-AC355F642DC3.jpeg
    333.2 KB · Views: 47
  • 3F8795E8-8777-4EA5-816F-E863302A5040.jpeg
    3F8795E8-8777-4EA5-816F-E863302A5040.jpeg
    371 KB · Views: 45

Cruiser

Chumono
Messages
664
Reaction score
1,443
Location
Western Washington
USDA Zone
8a
6/10: Lots of rain. More is forecast for the coming days. Trees placed in shop to prevent overwatering. (They are still in poorly draining nursery soil).

A fan on low setting is gently circulating air around the needles to dry them a bit and provide good circulation.
 

Leo in N E Illinois

The Professor
Messages
11,341
Reaction score
23,292
Location
on the IL-WI border, a mile from ''da Lake''
USDA Zone
5b
Narrow base on cork bark pines is due to them being the result of grafting. This is NORMAL, the common situation. There are a very small number of cultivars that can be air layered, it is a slow process, usually taking 2 years to get a seedling size tree going. The air layer is always done on new, 2 or 3 year old branches, not on wood old enough to have begun developing corky bark.

@Brian Van Fleet and @Adair M have given you the best advice out there on corkers. I have tried raising cork bark JBP myself off and on since 1980, and I can tell you, they die a lot. They are not as vigorous as JBP. JBP are marginal in my zone 5 climate, and cork bark JBP must be treated as "tender subtropicals" in my zone 5b climate. Over the decades I have had at least 10 or more, usually one or two at a time. And if the cool "Lake Effect" spring I have doesn't get them the needle cast will. Corkers need warmth, over 80 F days to "wake up" in spring, and they need a 150 day or longer growing season to be happy. The need a mild winter, they will not tolerate temperatures significantly below freezing. (here my winters will get to -10 F or -23 C). A little frost is okay but deep freeze is not good. Best to plan a cool but frost free winter location.

Even when I winter them in a frost free environment, they do not push candles for me until July due to my cool weather in spring. This slow growth means no decandling as a foliage management technique. No decandling ever in cool climates. Maybe "sometimes" in a hotter, longer season climate. Note: Remember with normal JBP decandling is done about 100 days before average first frost for your growing season. A corker often will not have strong enough candles by that date even if you are growing in Georgia or California, but mark your calendar, and evaluate. For the corkers, give them a little extra time, IF you going to decandle, make the decision perhaps 120 days before average first frost.

Point is, they are a weaker type of tree, I currently have none alive, and no longer delude myself that I can grow them with any success. Absolutely keep diligent about needle cast, there is a very high probability that this will be the cause of death of your corker.
 

Cruiser

Chumono
Messages
664
Reaction score
1,443
Location
Western Washington
USDA Zone
8a
Narrow base on cork bark pines is due to them being the result of grafting. This is NORMAL, the common situation. There are a very small number of cultivars that can be air layered, it is a slow process, usually taking 2 years to get a seedling size tree going. The air layer is always done on new, 2 or 3 year old branches, not on wood old enough to have begun developing corky bark.

@Brian Van Fleet and @Adair M have given you the best advice out there on corkers. I have tried raising cork bark JBP myself off and on since 1980, and I can tell you, they die a lot. They are not as vigorous as JBP. JBP are marginal in my zone 5 climate, and cork bark JBP must be treated as "tender subtropicals" in my zone 5b climate. Over the decades I have had at least 10 or more, usually one or two at a time. And if the cool "Lake Effect" spring I have doesn't get them the needle cast will. Corkers need warmth, over 80 F days to "wake up" in spring, and they need a 150 day or longer growing season to be happy. The need a mild winter, they will not tolerate temperatures significantly below freezing. (here my winters will get to -10 F or -23 C). A little frost is okay but deep freeze is not good. Best to plan a cool but frost free winter location.

Even when I winter them in a frost free environment, they do not push candles for me until July due to my cool weather in spring. This slow growth means no decandling as a foliage management technique. No decandling ever in cool climates. Maybe "sometimes" in a hotter, longer season climate. Note: Remember with normal JBP decandling is done about 100 days before average first frost for your growing season. A corker often will not have strong enough candles by that date even if you are growing in Georgia or California, but mark your calendar, and evaluate. For the corkers, give them a little extra time, IF you going to decandle, make the decision perhaps 120 days before average first frost.

Point is, they are a weaker type of tree, I currently have none alive, and no longer delude myself that I can grow them with any success. Absolutely keep diligent about needle cast, there is a very high probability that this will be the cause of death of your corker.
Thanks Leo for the detailed post. More knowledge in the bank.

My plan for these pines is purely to promote vigor and make them happy. No messing around. I’m playing favorites.


The candles have started pushing and some needles have emerged. Though numerous, most of the candles are tiny. It appears that small buds further back on the branches have become more active in the last week.

Another application of mancozeb will get applied 6/17 (10 days after first application).
 

junmilo

Shohin
Messages
465
Reaction score
363
Location
Ontario, Canada
USDA Zone
5
Nice, any idea what variety?
Given your location, when do the candles typically push and how long do they get?
Here are some pics of the candles and size..

They start pushing around end of April...its strange that this year almost all had male pollens on..

20220611_172638.jpg
20220611_172645.jpg
20220611_172652.jpg
20220611_172659.jpg
20220611_172705.jpg
 

Cruiser

Chumono
Messages
664
Reaction score
1,443
Location
Western Washington
USDA Zone
8a
Here are some pics of the candles and size..

They start pushing around end of April...its strange that this year almost all had male pollens on..

View attachment 441580
View attachment 441581
View attachment 441582
View attachment 441583
View attachment 441585
Good pics, thanks. Those candle lengths are about where mine are at except for the tall boy in pic 3.
Most of those needles look healthy. Do you spray to prevent needlecast?
 

LunaticTree

Yamadori
Messages
81
Reaction score
65
Location
Austria
USDA Zone
6
This is such a pretty Tree oh my.... I cant wait when you style it! It will be looking so awesome!
 

junmilo

Shohin
Messages
465
Reaction score
363
Location
Ontario, Canada
USDA Zone
5
Good pics, thanks. Those candle lengths are about where mine are at except for the tall boy in pic 3.
Most of those needles look healthy. Do you spray to prevent needlecast?
We are restricted to little or nothing up here in the north. I spray copper fungicide early in the spring..
 

Cruiser

Chumono
Messages
664
Reaction score
1,443
Location
Western Washington
USDA Zone
8a
Second application of mancozeb.

I tried using plastic wrap this time to keep it out of the soil. It was hard to get a tight seal and the fungicide sort of pooled on the plastic, but I think it did the job.

It’s raining. Spraying was done under a shelter to prevent the mancozeb from rinsing off too quickly.
 

DeadwoodOriginal

Seedling
Messages
12
Reaction score
4
Location
Northwes Illinois
USDA Zone
5a
Narrow base on cork bark pines is due to them being the result of grafting. This is NORMAL, the common situation. There are a very small number of cultivars that can be air layered, it is a slow process, usually taking 2 years to get a seedling size tree going. The air layer is always done on new, 2 or 3 year old branches, not on wood old enough to have begun developing corky bark.

@Brian Van Fleet and @Adair M have given you the best advice out there on corkers. I have tried raising cork bark JBP myself off and on since 1980, and I can tell you, they die a lot. They are not as vigorous as JBP. JBP are marginal in my zone 5 climate, and cork bark JBP must be treated as "tender subtropicals" in my zone 5b climate. Over the decades I have had at least 10 or more, usually one or two at a time. And if the cool "Lake Effect" spring I have doesn't get them the needle cast will. Corkers need warmth, over 80 F days to "wake up" in spring, and they need a 150 day or longer growing season to be happy. The need a mild winter, they will not tolerate temperatures significantly below freezing. (here my winters will get to -10 F or -23 C). A little frost is okay but deep freeze is not good. Best to plan a cool but frost free winter location.

Even when I winter them in a frost free environment, they do not push candles for me until July due to my cool weather in spring. This slow growth means no decandling as a foliage management technique. No decandling ever in cool climates. Maybe "sometimes" in a hotter, longer season climate. Note: Remember with normal JBP decandling is done about 100 days before average first frost for your growing season. A corker often will not have strong enough candles by that date even if you are growing in Georgia or California, but mark your calendar, and evaluate. For the corkers, give them a little extra time, IF you going to decandle, make the decision perhaps 120 days before average first frost.

Point is, they are a weaker type of tree, I currently have none alive, and no longer delude myself that I can grow them with any success. Absolutely keep diligent about needle cast, there is a very high probability that this will be the cause of death of your corker.
Do you suppose a greenhouse might help extend their season enough to keep them healthy? Or, is it maybe a matter of daylight? I ask because im about 3.5 hours west of the city, and have been considering picking a few up, but have concerns about getting them to thrive. I have a couple 600 watt HPS lights that could help suppliment a few extra months. I dunno, just something ive been thinking about. You seem like you know what your talking about with trees in zone 5, so i would certainly defer to your judgement
 

Leo in N E Illinois

The Professor
Messages
11,341
Reaction score
23,292
Location
on the IL-WI border, a mile from ''da Lake''
USDA Zone
5b
I "dunno". I have tried for years to keep corkers going in the northern suburbs of Chicago. It can be done, Chicago Botanic Garden has a couple examples they keep going year after year. I tried to winter mine in a well house, or under lights. Over time (say a 10 year period) my failure rate was 100%. The Chicago Botanic Garden winters their cork bark JBP in cool, slightly above freezing GREENHOUSE. If you don't have a cool greenhouse, I would be dubious of your long term success. I did successfully winter them a few years, but eventually, over a 5 or so year period they eventually failed.

As others have said, they are winter hardy thru maybe zone 7b, possibly 7a, but it is difficult to predict the night before just how cold the low will be and the duration of the cold will be and how it will effect the tree in the pot on your bench. So in the Chicago region or west of the city in Illinois, it is best to protect from cold below say +27 F, or somewhere around there. The move the tree to a cool greenhouse.

I found under 400 watt HPS, I had trouble adjusting to their new watering regime. I had them situated with my orchids. They needed water more often than the "every 5 day" orchids, and less water than the "want daily water" orchids. I never got the water frequency right. Dead trees by the end of the winter. Damned if you do, damned if you don't.

The no light, cool well house, temps 35 to 40 F, worked better. I successfully wintered there for a fair number of years. But the issue of accidentally getting the trees into the well house too late in the season, exposing them to excess cold. Or issues getting them out too early in spring, requiring the "in and out" dance in spring to avoid cold frosty nights in spring, always eventually resulted in an eventual screw up.

Bringing trees out of the well house, (or an equivalent like a deep cold frame) is always tricky. Late freezes are an issue.

End result, is I have no cork barked pines left. Its not that one can not do them in zone 5. The issues is that over time, there are many things that can go wrong. If you are diligent, careful, you can avoid early autumn hard freezes, and avoid late spring freezes. But eventually, you make a mistake. Or at least I did.

But heck. You should try. Especially if you can eventually set up a cool greenhouse for wintering the cork bark JBP in zone 5.
 

DeadwoodOriginal

Seedling
Messages
12
Reaction score
4
Location
Northwes Illinois
USDA Zone
5a
I "dunno". I have tried for years to keep corkers going in the northern suburbs of Chicago. It can be done, Chicago Botanic Garden has a couple examples they keep going year after year. I tried to winter mine in a well house, or under lights. Over time (say a 10 year period) my failure rate was 100%. The Chicago Botanic Garden winters their cork bark JBP in cool, slightly above freezing GREENHOUSE. If you don't have a cool greenhouse, I would be dubious of your long term success. I did successfully winter them a few years, but eventually, over a 5 or so year period they eventually failed.

As others have said, they are winter hardy thru maybe zone 7b, possibly 7a, but it is difficult to predict the night before just how cold the low will be and the duration of the cold will be and how it will effect the tree in the pot on your bench. So in the Chicago region or west of the city in Illinois, it is best to protect from cold below say +27 F, or somewhere around there. The move the tree to a cool greenhouse.

I found under 400 watt HPS, I had trouble adjusting to their new watering regime. I had them situated with my orchids. They needed water more often than the "every 5 day" orchids, and less water than the "want daily water" orchids. I never got the water frequency right. Dead trees by the end of the winter. Damned if you do, damned if you don't.

The no light, cool well house, temps 35 to 40 F, worked better. I successfully wintered there for a fair number of years. But the issue of accidentally getting the trees into the well house too late in the season, exposing them to excess cold. Or issues getting them out too early in spring, requiring the "in and out" dance in spring to avoid cold frosty nights in spring, always eventually resulted in an eventual screw up.

Bringing trees out of the well house, (or an equivalent like a deep cold frame) is always tricky. Late freezes are an issue.

End result, is I have no cork barked pines left. Its not that one can not do them in zone 5. The issues is that over time, there are many things that can go wrong. If you are diligent, careful, you can avoid early autumn hard freezes, and avoid late spring freezes. But eventually, you make a mistake. Or at least I did.

But heck. You should try. Especially if you can eventually set up a cool greenhouse for wintering the cork bark JBP in zone 5.
thanks, i appreciate the feedback. I think I will hold off for a bit. Perhaps when I retire I would have the time to really baby a few special cultivars. Corkbarks are one of my bucket list trees, and i would really want one to thrive and not simply make it through a few seasons. Im sure i will have plenty of other questions for you in the months ahead..thanks again.
 
Top Bottom