They are not signs of maturation. They are tiny necrotic patches that can be caused by any number of plant pathogens. They are quite common, and not worrisome.
Bob
Bob
Tobaccofieldsforever 2021 Grow Log
- Thread starter Tobaccofieldsforever
- Start date
- Status
Oldfella
Well-Known Member
Just a point of interest. When I magnified the picture I noticed a lot of black buggy looking spots on the stems, any idea what they are?
Not bugs I hope
Oldfella
Not bugs I hope
Oldfella
Tobaccofieldsforever
Well-Known Member
Just dirt, insect poop, etc... A lot of it was covered with corn tassles too. It had not yet been cleaned at all when picture was taken.Just a point of interest. When I magnified the picture I noticed a lot of black buggy looking spots on the stems, any idea what they are?
Not bugs I hope
Oldfella
Tobaccofieldsforever
Well-Known Member
After leaves are harvested and before they are cured how do people clean them? I have read about dipping them in soapy water and rinsing them, using a dry, clean paint brush and just brushing sediment off the lamina, etc... I read @deluxestogie recommend to someone to avoid harvesting wet leaf (let the dew evaporate), why is this? Also on a nearly entirely unrelated topic, what are some cons of letting leaf become "over ripe" before priming? To me, it seems like if the color curing process is going to involve letting the leaf yellow in ambient environmental conditions can't it just yellow on the plant where it will for sure be provided with what it needs to not dry out during that process or is there something happening on a chemical level when the leaf is removed from the stalk? I know this is kind of the idea behind stalk harvesting but I guess my question is why not just leave the plant where it is growing while the leaves yellow more?
If you carry wet leaf into a curing shed, the humidity will skyrocket, and increase the risk of mold and barn rot.
When I prime leaf, I make sure it is dry enough for any dirt to be easily brushed off with my fingertips. Then I flick away any seeds, clippings, dead gnats and other kibbles and bits, prior to stringing. Even dried bird shit just gets brushed away with my fingers. For stalk-cut plants, my cleaning is not as thorough. But regardless, I never carry wet leaf into the shed.
As leaf yellows and progresses toward brown, the leaf becomes stiffer and more brittle. That means that it is more subject to damage from weather, if left out in the field. Also, once leaf is brown, it's quality is compromised by being exposed to rain.
If there is something so awful, so truly icky, so disgustingly foul on some nice leaf, then I may gently hose it in the field (still attached to the standing stalk), and wait for it to thoroughly dry, prior to priming or stalk cutting. My most common debris is grass clippings (my fault), dried mud (on the lower leaves), insect egg clusters, dead gnats (their fault), corn anthers, pine seeds, milkweed silks, dried tree leaves, occasional feather bits.
There are no rules. I simply try to weigh the risks of my choices. Dirty leaf can be cleaned after kilning. Some members successfully rinse their primed leaf without an issue. I don't recall anyone using soapy water on primed leaf.
Bob
When I prime leaf, I make sure it is dry enough for any dirt to be easily brushed off with my fingertips. Then I flick away any seeds, clippings, dead gnats and other kibbles and bits, prior to stringing. Even dried bird shit just gets brushed away with my fingers. For stalk-cut plants, my cleaning is not as thorough. But regardless, I never carry wet leaf into the shed.
As leaf yellows and progresses toward brown, the leaf becomes stiffer and more brittle. That means that it is more subject to damage from weather, if left out in the field. Also, once leaf is brown, it's quality is compromised by being exposed to rain.
If there is something so awful, so truly icky, so disgustingly foul on some nice leaf, then I may gently hose it in the field (still attached to the standing stalk), and wait for it to thoroughly dry, prior to priming or stalk cutting. My most common debris is grass clippings (my fault), dried mud (on the lower leaves), insect egg clusters, dead gnats (their fault), corn anthers, pine seeds, milkweed silks, dried tree leaves, occasional feather bits.
There are no rules. I simply try to weigh the risks of my choices. Dirty leaf can be cleaned after kilning. Some members successfully rinse their primed leaf without an issue. I don't recall anyone using soapy water on primed leaf.
Bob
Tobaccofieldsforever
Well-Known Member
The soapy water suggestion is from good ol Jim Johnson. He suggests bringing a bucket of soapy water and a bucket of clean water to rinse with and dipping primed leaf in them (speaking of strange advice from the other post). I was actually asking about that because of bird shit and something else that is probably bird shit too that I haven't identified yet. Thank you for the advice!
The trichomes on the upper surface of tobacco leaf secrete alkaloids. (That's what kills those wayward gnats.) It is water soluble, and rinses away every time it rains. But with leaf that is still alive and attached to a living plant that is still attached to its roots (the plant's nicotine factory), the leaf's trichomes promptly replenish their anti-herbivore coating of alkaloids.
If you rinse primed leaf, or even leaf on a stalk-cut plant, there is no longer a source for nicotine replenishment. How much of an impact does that make on the quality of the cured leaf? Probably not a lot, but definitely not zero impact.
Bob
If you rinse primed leaf, or even leaf on a stalk-cut plant, there is no longer a source for nicotine replenishment. How much of an impact does that make on the quality of the cured leaf? Probably not a lot, but definitely not zero impact.
Bob
Tobaccofieldsforever
Well-Known Member
Good to know! Thank you! And now for something completely different: My burley is making me feel like I don't have a clue what I'm doing. Whether that is true or not is maybe beside the point. It seems to be maturing rapidly before it has flowered. At first I thought maybe it needed water as it has been very hot (90 degree days and no rain for a while now) so I watered it but it does look more like leaf maturation. I remember reading that burley yellows before other varieties. I don't know what variety it is. It was sold to me as "burley" seedlings from a local farm market. It seems to be a good ways off from flowering and my other two varieteies already have flowers that are dying. Any suggestions?
Photos would help.
Have you seen BigBonners burley topping video? It was made during a dry year and could help you gauge yours.
Tobaccofieldsforever
Well-Known Member
These arent very large but they both survived flooding (I didn't think either of them would) and are growing at angles from being blown over multiple times (resetting didn't take). Below is my other burley plant that didn't get quite as abused by the weather and also doesn't seem to be yellowing quite as much. But in the beginning, before all the weather happened, this plant was small and behind:
I would not be concerned about them. The nearly-drowned ones look great, and you could prime the bottom leaf, or wait for the tops to fully mature, then stalk-cut. (You could probably stalk-cut today, and have them stalk-cure well.) Their near-death experience kind of resets the plants' priorities.
Bob
Bob
Oldfella
Well-Known Member
Phew! I'm pleased that's all it is. That means most of it will fall off as you handle them.
Oldfella
Tobaccofieldsforever
Well-Known Member
Some of my leaves that I am air curing/ yellowing in the shade are turning a blackish color. The leaf isnt dry yet so it isn't flash drying. Here's a picture of a brightleaf leaf.
You're air-curing them on the grass?
Bob
Bob
Tobaccofieldsforever
Well-Known Member
no, I put them there for the picture. The lighting was better there. I will admit I have thought about that though because I read on this site that someone cured their leaves by laying them in the lawn and it worked well. Is the black/dark green a bad sign?
Needed context: what variety, at what stage was it primed, what stalk level, how was is being air-cured (conditions), for how long has it been air curing?
My immediate thought is that it looks like blue mold.
Bob
Tobaccofieldsforever
Well-Known Member
yikes. This picture is upper/midstalk bright leaf. It appeared ripe when primed, the plant was topped at least two weeks ago (I can't remember exactly when...oops). I am yellowing/wilting it in the shade with the intention of sun curing it. It is hanging from a tree branch by wire I ran through the stem. It is in all day shade. Hot, dry days (upper 80's, lower mid 90's) unseasonably cold nights (upper 50's lower 60's). It is usually soaked with dew in the morning but has only been "curing" for a few days now. I have seen this kind of blackening before on greenish leaf put in the sun. These are kind of experimental leaves I primed to try and figure out how things would cure in this weather. (I may have a picture of them right after priming)
Tobaccofieldsforever
Well-Known Member
@deluxestogie it's almost as if they are skipping the yellowing stage and going straight to browning and that is the resultant color while still wet/alive (maybe wishful thinking). Is this something that can happen?
My experience with sun-curing is to hang the leaf in the sun, with the purpose being to yellow the leaf as rapidly as possible, then sun-dry it that way. I have not attempted to sun-cure flue-cure varieties.
Blue mold of tobacco is a specific pathogen (Peronospora tabacina). There are all sorts of bacteria and fungi that can cause darkening and necrosis of the lamina. Does the photo show necrosis? I can't tell. But time will tell. Could be just some hinky coloring, or could be rotting from some other bug.
Assuming your general approach (yellow in the shade, then sun-cure, which a number of forum members accomplish successfully), I would be inclined to select shade that is less likely to accumulate dew each morning--say, in a shed. Or do the yellowing in a box.
Maybe our other members can provide more useful advice about this.
AND...you have to post some time sequence photos of what happens to that specific leaf over the next week or so. Please.
Bob
Blue mold of tobacco is a specific pathogen (Peronospora tabacina). There are all sorts of bacteria and fungi that can cause darkening and necrosis of the lamina. Does the photo show necrosis? I can't tell. But time will tell. Could be just some hinky coloring, or could be rotting from some other bug.
Assuming your general approach (yellow in the shade, then sun-cure, which a number of forum members accomplish successfully), I would be inclined to select shade that is less likely to accumulate dew each morning--say, in a shed. Or do the yellowing in a box.
Maybe our other members can provide more useful advice about this.
AND...you have to post some time sequence photos of what happens to that specific leaf over the next week or so. Please.
Bob
Some articles regarding Blue Mold. One of the diagnostic approaches is a cut in the stalk and look for brownish streaks. There are photos in there of the brownish streaks.
In this article, you will need to select different headers to view all the information, An Intro, Main Symptoms, Protection Methods, Biology and Entymology.
ephytia.inra.fr
burleytobaccoextension.ca.uky.edu
In this article, you will need to select different headers to view all the information, An Intro, Main Symptoms, Protection Methods, Biology and Entymology.
Tobacco - Blue mould, Downy mildew (Peronospora hyoscyami f.sp. tabacina)
Tobacco - Blue mould, Downy mildew (Peronospora hyoscyami f.sp. tabacina)
Blue Mold | Burley Tobacco Extension
Systemic blue mold can be severely damaging to plants after an outbreak shortly after transplanting. Infected plants may not show symptoms of systemic blue mold until later as plants attempt to grow. Plants will appear stunted and will yellow. These plants will not be productive. A cut through...
burleytobaccoextension.ca.uky.edu
Last edited:
- Status
