Trees, forests, and forestry

[Ahmed]

If it is possible to plant after the resumption of general sap, it is precisely that the plants have been artificially kept dormant, which shows the plasticity of the plants and the possibility of "manipulating" them (to a certain extent) a once we understand the mechanisms involved. hutch indicates that the resumption of rooting does not only establish itself just before spring.

I doubt that many people think that the roots grow for some periods of dormancy of the aerial part (and that is completely indifferent to me), but you are free to check it by following the protocol that I indicated previously: maintenance of dormancy at the top, caloric stimulation of growth down...
There is all the same a biological logic behind all this, because it would be difficult to imagine a resumption of a plant if everything starts at the same time, given the situation of imbalance of the plant; we cannot therefore start on this hypothesis; just saying...

[Moindreffor]

Moindreffor, I am, with a few nuances, agree with your first and second paragraph.
On the first, it is necessary to relate the useful time to the periods when the soil is sufficiently warm to allow the functioning of the roots and not an "abstract" weather. , but overall your reasoning is good. I think we win in planting before Ste Catherine decides ...
On the second, it is not in bad taste that scientists are looking into the question, but I am no longer aware of current research.

The argument of Sicetaitsimple concerning the uprooting does not hold, because the plants are precisely uprooted early in the fall and stored in humidified refrigerators where they wait for the barge.

As for the practitioners cited, their approach is more commercial than technical. Note, however, the last sentence of the nurseries hutch:

...but more difficult the dry springs if they are planted late.

indeed it's like everything, the leek is a bit like the trees, it continues to grow in winter, it is not dazzling but it grows, and for that beyond the simple calendar which counts the days, it is necessary to count the useful days, those when the temperature is high enough for it to grow, which you get around by placing your layers in a warm layer

for the interest of scientists, I think that funding implies research choices and therefore why go and spend funds to prove what you observe so easily with your warm diapers, would by protocolizing this, we would improve the practice? ? Knowing exactly what is happening to the nearest degree is that really useful, since outdoors you will never adjust the thermostat.

[Moindreffor]

As for the practitioners cited, their approach is more commercial than technical. Note, however, the last sentence of the nurseries hutch:

...but more difficult the dry springs if they are planted late.

The preceding sentence says: "they must be established before the resumption of vegetation (end of March) so that their root system has time to settle "; This means that, if they are planted before the resumption of vegetation, the root system has time to settle (it settles when the vegetation resumes).

Again, you (like many people) believe that the roots grow during the dormant period, but you are unable to provide proof. If you provide any evidence, I am prepared to take it into account; but otherwise, I stop there.

The argument of Sicetaitsimple concerning the uprooting does not hold, because the plants are precisely uprooted early in the fall and stored in humidified refrigerators where they wait for the barge.

In practice, they are often gauge outside in sand.
For the rest, companies make a planning of planting over the whole winter, and if, at some point, they cannot plant (because it is freezing, or because it rains too much), they postpone or postpone . So, very often, they make their last plantings in April, when the vegetation is starting to resume. It's sub-optimal, but if the terrain is wet enough (including in summer), it's fine. In waterlogged areas, this is even the only solution, because in the middle of winter, they are impassable.

Ahmed told you that by placing his layers in hot layers he observed a root development, for me this observation is sufficient

to field observations you oppose commercial and business management arguments, it is obvious that professionals will extend their planting ranges as much as possible, it is personnel management, and in garden centers, we push the plug even further by selling potted trees that you can buy and replant in any season, you can buy an apple tree with apples on it and you will just be told to remember to water it well ...

it's like seed packets, we give sowing dates but are they the same dates whether you live in the South or in the North? you will sow beans in March-April in the South and you will wait until the end of May at the beginning of June in the North, and there is no need for scientific studies ... so why blame for the rooting of the trees?

[Ahmed]

Below, a photo taken today (Dec. 3) of a birch tree: on the left side, note the lighting angle of the lamppost and the influence that the artificial lengthening of the day has on the only lit part. Although the tree is obviously a well-individualized organism, there is no centralization of "decisions" and each part sees the biological mechanism reacting to the trigger criteria, here the length of the day, which has resulted in the major part. of the branches a total defoliating *. We can clearly see that the longer-lit part retains its leaves, without even yellowing. Only a slightly marked frost will cause leaves to fall to the ground still green, since the minimum lighting duration required to start the process will never be reached.

This is why it is not surprising that the above-ground and underground parts, subjected to environmental constraints, react differently, thus adapting best to each situation, as do similar bodies, such as branches.

* By means of an auxin, called absissic, which causes necrosis of the base of the petiole of each leaf. Note that this tree does not represent a special case and that this observation that you can all make applies to all deciduous trees and shrubs.

IMG0088B (2) .jpg (298.96 KiB) Viewed 2311 times

[Ahmed]

Initially, I wanted to take a photo of a willow, which is the cause of the blunder in the comment of the previous post: the willow keeps its green leaves, while the birch sees the process of leaf necrosis stop a little later , when the leaf begins to depigment. Basically, this obviously does not change the phenomenon, which varies a little depending on the species.

[Ahmed]

A video by the botanist Francis Hallé, interesting in quite a few respects, even if his insistence on talking about humans as if they were a homogeneous whole is very questionable (we will say that it is a shortcut!):

[VetusLignum]

I doubt that many people think that the roots grow for some periods of dormancy of the aerial part (and that is completely indifferent to me), but you are free to check it by following the protocol that I indicated previously: maintenance of dormancy at the top, caloric stimulation of growth down... :

Once again, it is in the natural environment in which the plants have evolved that we want to observe things.
You can create various artificial conditions, or have fun planting our temperate climate trees in tropical conditions, you will certainly observe a number of surprising things, but that is not what interests us.

indeed it's like everything, the leek is a bit like the trees, it continues to grow in winter, it is not dazzling but it grows, and for that beyond the simple calendar which counts the days, it is necessary to count the useful days, those when the temperature is high enough for it to grow, which you get around by placing your layers in a warm layer

But anyway, a leek is not like a tree: the leek has green leaves, it photosynthesizes, so it grows.
Note, however, that so far we have only talked about deciduous trees, which lose their leaves in autumn, and are dormant during winter.
Evergreen trees don't really go dormant, and could indeed be compared to leeks.

Note also that only dormant trees are sold bare roots, the others are sold in pots.

Why don't you sell bare rooted evergreens?
Not all trees are available bare rooted, as some don't enjoy being transplanted this way. Evergreens are almost never available bare rooted as they don't go into full dormancy, so most of our bare root stock are deciduous trees (ones that lose their leaves).

Why can't I buy a bare root tree in summer?
A bare root tree is dug up from the ground while it's dormant (after it loses its leaves and before they come back in the spring). At this time, it can be transplanted without the soil its roots were growing in. You can't remove the soil from the roots in the growing months, as the roots would dry out quickly and the tree could die. Even in winter, you should plant a bare root tree as soon as possible after receipt.
https://www.chewvalleytrees.co.uk/guide ... -container

For deciduous trees, growth restarts in early spring, when the trees sense a number of factors in the environment:

When the tree detects lengthening daylight hours and a pattern of rising temperatures, it knows it's ready to leave dormancy and burst those overwintered leaves from their buds. How exactly it works out that spring has come, scientists are still trying to work out. What this means for tree planters, however, is that it's no longer safe to plant bare root trees and hedging, as the plants are in active growth again and so exposed roots run the risk of the plant drying out. Container-grown is the way to go, from about mid-March.
https://www.chewvalleytrees.co.uk/blog/ ... -in-winter

We can also see that these plants are very adapted to the environment in which they have evolved, and that, on the one hand, observing them in an artificial environment does not make sense; and on the other hand, climate change can strongly disrupt them (for example, we can see some cherry trees bud in January if the weather is very mild)
https://esajournals.onlinelibrary.wiley ... /ecs2.2542

to field observations you oppose commercial and business management arguments, it is obvious that professionals will extend their planting ranges as much as possible, it is personnel management, and in garden centers, we push the plug even further by selling potted trees that you can buy and replant in any season, you can buy an apple tree with apples on it and you will just be told to remember to water it well ...

I brought practitioner observations because Ahmed didn't want to make a scientific argument.
Then, in a market, supply and demand adjust to each other; it's like in a concert, if some places sell for more than others, it is not only because of the greed of the organizers, it is also because some customers are ready to pay more to benefit of various advantages.

[VetusLignum]

It seems to me that we do not always have a good understanding of deciduous perennial plants.
We tend to believe that it is the roots that make the plant live, when in reality, it is much more complex: the roots certainly provide water and essential minerals, but the energy that makes the plant grow. plant comes from photosynthesis, and therefore from the leaves. Thus, the growth of plants is nourished by photosynthesis, bud break in spring is done by means of the energy put in reserve the previous year, and therefore, in winter, the plant saves its reserves in order to succeed in its budding when the spring is coming.


Marceau Bourdarias explains it well in these videos:

[izentrop]

the roots certainly provide water and essential minerals, but the energy that makes the plant grow comes from photosynthesis, and therefore from the leaves. Thus, the growth of plants is nourished by photosynthesis, bud break in spring is done by means of the energy put in reserve the previous year, and therefore, in winter, the plant saves its reserves in order to succeed in its budding when the spring is coming.

This does not prevent the roots from continuing to grow as long as the temperature of the soil is not too low (dixit Ahmed et al).
It is also logical by the fact that the sap descended in the fall contains all the necessary nutrients. At the trunk and bark level, starch is stored and turns into sugar which serves as an antifreeze

Evergreen trees don't really go dormant, and could indeed be compared to leeks.

In winter, trees, whether deciduous (those that lose their leaves) or evergreen, cease all growth activity ...

As soon as the temperature drops below 5 ° C, the tree synthesizes enzymes which will degrade the starch produced by photosynthesis and stored in the summer months in the bark and wood. As soon as the temperature rises above 5 ° C, even in winter, the starch is reconstituted because the antifreeze proteins fuse together to reform it.
Then, when the temperature drops again in the evening, it is hydrolyzed again, and so on.
If the walnut can withstand a maximum of -20 ° C, the needles of the Pinus sylvestris pine can still survive in -80 ° C! ...
https://www.onf.fr/onf/+/925::quelle-es ... #4004257_3

[VetusLignum]

This does not prevent the roots from continuing to grow as long as the temperature of the soil is not too low (dixit Ahmed et al).

This idea is indeed very widespread, it is found repeated by many sources, I also believed in it until recently.
But since I questioned it and researched it, I don't believe it anymore; and so far, I have not been presented with any scientific reference to make me believe it again.