How are pine trees pollinated
How Do Pine Trees Reproduce? – The Tree Care Guide
Your pine tree’s annual reproductive cycle can indicate its good health, or that you need to take action. Knowing how your pine tree reproduces can help you better care for it and give you valuable insight into its strong or declining health.
thetreecareguide.com gathered information on what pine trees do to reproduce and the startling information this process reveals.
All forms of life share the drive to survive and reproduce. Trees are not exempt from this and have developed two main strategies to accomplish their reproduction:
Angiosperms – These are trees that produce flowers and rely heavily on pollinating insects and wildlife to carry their genetic material from one tree to another.
Gymnosperms – These are non-flowering trees or conifers (including pine trees). These trees produce pollen as well but have different means of achieving their reproductive goal. (These trees date back to prehistoric times)
Both types of trees reproduce through seeds but have very different strategies for how that seed is produced.
Pine Tree Reproduction
For a pine tree to successfully reproduce, 3 distinct steps must take place:
Step 1 – The first step in pine tree reproduction is pollination. For pollination to happen successfully, pollen must be transferred from male cones to female cones.
While pine trees grow both male and female cones, the intention is not to self pollinate. Female cones are produced high up in the crown of the pine tree, while male cones (catkins) are produced on the branches below.
Male pine cones do not look like the pine cones many are used to seeing but are long, thin, and soft structures located in clusters on the lower branches. Male cones are only present in the spring when producing pollen.
Pollen is carried from the male cones of one tree to the female cones of another by wind currents. Thus, completing the first step of reproduction.
Read more about tree pollen at thetreecareguide.com/tree-pollen-allergy-season/
Step 2 – Once the female cones have been pollinated, they will produce fertile seeds within the closed cone. It takes about two years for this step to complete itself. As the cone becomes brown, it develops scales, opens up, and resembles the familiar pine cones we all know.
At the base of each scale on a female pine cone, a seed lies waiting to be carried off by the wind or wildlife. Thus, completing the second step of the tree’s reproduction.
Step 3 – Seed dispersal is the final step in a pine tree’s reproductive cycle, and even this step displays how brilliant nature is. As the female cones open up, several species of birds and squirrels come along to feed on the seeds, potentially dispersing them miles away from the parent tree.
Sometimes, the pine cones are knocked off or fall off the tree. The shape and flexibility of cones allow them to bounce and roll away from its origin while dispersing its seeds.
Then there are those cones that remain closed until exposed to extremely high temperatures, like those temperatures produced in a forest fire. These cones only release seeds under such conditions, likely corresponding to the death of the parent tree in a fire.
Tip: When planting a pine tree on your property, it is smart to plant more than one. By doing this, you can all but guarantee the successful annual pollination of your trees and dispersal of viable seeds.
Pine Tree Health
The healthier you maintain your pine trees, the better they will be at reproducing annually. Likewise, when a pine tree is under stress from drought, has suffered a successful insect infestation, or has been infected by a disease, it may do something peculiar.
When your pine tree is stressed, damaged, or dying, it may produce a stress crop. A stress crop would look like an explosion of pine cones maturing in the upper branches and falling from the tree.
Producing a stress crop is one of the measures pine trees utilize to guarantee the continuation of their species. It also serves as an alarm bell for humans to take a closer look at the tree. Some infestations and diseases can be treated, while others may require the removal of the tree to protect other trees on or near your property.
If your pine tree is producing a stress crop or has developed signs of disease, call a professional tree service to inspect it and offer a course of action to either restore its health or remove it.
Read about how you can save a dying evergreen at thetreecareguide.com/how-to-save-dying-evergreen/
How A Pine Tree Reproduces
In this article, you discovered how pine trees reproduce and how that reproduction may indicate trouble for your tree.
By caring for your pine trees and knowing how they reproduce, you can detect signals that tell you when the tree is stressed, and when to call for help.
Ignoring your pine tree through its reproductive cycle may lead to its decline in health and eventual death.
Tags:Caring For TreesDying TreeFemale Pine ConesHow Do Trees ReproduceMale Pine ConesPine ConesPine TreesPollenStress CropThe Tree Care Guidetreetree careTree DiseaseTree HealthTree Illness
How Do Pine Trees Reproduce? (Full Reproduction Cycle)
Unlike deciduous trees, coniferous trees like pine trees (Pinus spp.) reproduce using their cones. The process is complicated, so if you’ve ever wondered just how do pine trees reproduce, read on!
As a general rule, most trees – pine trees included – reproduce sexually. This means that both male and female parts of the pine tree are required for fertilization and for a seed to develop.
How Does Pine Tree Pollination Work?
A pine tree is a gymnosperm. Literally meaning “naked seeds”, gymnosperm plants have seeds that are not encased within an ovary. Often, these seeds are formed into cone shapes like in the case of the pine and other conifers.
The vast majority of pine trees are monoecious, so they have both male and female flowers on the same tree. There are, according to the American Conifer Society, some species that are sub-dioecious, but not a great number. These species are predominately single-sex, but not entirely so.
The reproduction cycle of a pine tree is a part of its overall life cycle. In the spring, the male flowers or cones — because they are pine cones too, just not what we normally think of when we think of pine cones — produce one of the pine tree’s two types of spores: microspores.Photo by Buddha Dog on Flickr
Whereas a pine tree’s female flowers mature into the brown, scaly, cones we recognize, its male flowers are much smaller, softer cones. Often composed of pale yellow anthers, they grow at the tip of branches and are only present for a few weeks each spring.
These male microspores produce the pollen grains, scientifically known as gametophytes, that are carried by the wind to the newly budding female flowers with their megaspores. Usually, as mentioned above, these are also present on the same tree, but that doesn’t mean that pine trees are only fertilized by their own flowers; it just means that they can be.
Pine trees reproduce far more successfully when there are many of them together in the same area.
Male cones generally grow on the lower branches of pine trees, and female cones usually grow on the upper branches of pine trees. Pine pollen from the male flowers is picked up by the wind and carried far and wide.
If you’ve ever lived in a pine forest in the spring, you’ll know what I mean, and your windows will too when they’re covered in yellow-green pollen.
Once the male gametophytes reach the female flowers, at this stage just tiny, dark, often reddish-brown or purple cone buds at the tips of new pine shoots, they enter the flowers through their soft scales, which are still slightly separated at this stage.Photo by Puusterke on Wikimedia
The gametophyte pollen drifts down through the female flowers to the egg cells, borne in female gametophytes. Then, after a delay of up to two years in some cases, fertilization occurs. During that delay, a pollen tube develops, and the pollen grains undergo changes that develop them into sperm cells capable of fertilizing the eggs.
Once fertilization occurs and the pollen begins to change, the female flowers turn green, close, and develop into what you might recognize as a young pinecone. Over the next year or so, these cones mature.
Pine trees usually have cones of different ages and levels of maturity present at the same time due to the amount of time it takes for each to develop fully.Photo by cogdogblog at Flickr
The pine cones themselves, when mature, contain the seeds of the next generation. These seeds are held on each fertile scale of the cone, but not all scales are fertile: those at the base and tip are infertile. Seed dispersion normally happens via the wind, as most seeds are winged enough for wind-dispersion to occur.
Other seeds, however, are dispersed by birds as they have only a vestigial wing, i.e., a wing that is small and not able to function fully.
How Can You Tell if a Pine Tree is Male or Female?
The vast majority of pine trees are monoecious — both male and female. For the rare few that aren’t, check for cones. If you see only or almost only yellow, soft, flower-like cones for a few weeks in spring and never any mature pine cones or only very few, then the tree is most likely a sub-dioecious male.
Likewise, if you never or rarely see male cones and see only or mostly brown, hard, mature female cones, the tree is most likely a sub-dioecious female. This though, as far as I can ascertain, is very unusual.
Can You Grow a Pine Tree from a Pine Cone?
You can grow lots of pine trees from a pine cone! As each scale contains two seeds, and each pine cone is made of many scales, a great number of new pine trees could grow from each opened cone.
But opened is the key word. Until its seeds are ready to grow into new trees, a pine cone keeps its scales tightly closed. Some species of pine have cones that open without help when the seeds are mature, but others require specific conditions to prompt their scales to open.Photo by S. Rae on Flickr
Often, the specific conditions required amount to extreme heat, as in the case of a forest fire. Certain pine species have evolved and adapted to fire such that their seeds are only available after fire.
In landscapes prone to regular fires, as some are, this makes sense. It ensures that there will be a new generation of trees after current standing trees have been damaged or destroyed by fire, and it also protects seedlings and saplings from damage themselves as they tend only to sprout after fires, when all of the dead, dry, kindling material in the forest has been burned away and another fire is unlikely for some time.
However, this doesn’t mean that forests can regenerate easily or quickly after wildfires, and it certainly doesn’t mean that they can always recover after the scale of fires that have been seen recently. Pine trees and other species adapted to fire have evolved slowly, over millennia, and are accustomed to the natural rhythms of small-scale fires in particular landscapes.
They’re not, however, able to cope with large-scale, persistent fires motivated by climate change or human carelessness. What’s more, not all trees have adapted to fire, and even for those that have, the growth process from seed to mature tree is not a quick one.
But Don’t Plant a Pine Cone
If you want to grow and pine tree from seed, first find an open pine cone on the ground in a local forest; autumn is usually your best time of year. And try to make sure that any tree you grow or plant is native to your area. DO NOT, under any circumstances, ever, EVER light a fire in a woodland.
If you find an open cone, don’t plant the whole thing. It may not have any seeds left in it, or it may have many: just like you don’t want no trees, you also don’t want 40 trees all trying to grow in the same place!
If you can see any small, winged seeds present on the scales, tap the pinecone or give it a little shake to see if the seeds fall out on their own. If they don’t, remove them very, very carefully, and remember that they’re delicate.Photo by Kira Nash at kiakari
The exact germination process will vary depending on the species of pine in question, so as always, I recommend that you do some thorough research to learn exactly how best to handle your particular seeds.
Pine seeds often require stratification, which is a simulation of the natural changes in temperature, chilling and warming, that a seed would experience “in the wild”. As many seeds remain dormant until they’ve experienced certain conditions in a certain order, stratification can be essential.
Stratification can usually be achieved at home, but as there’s a lot of variation in what seeds need, it’s always wise to know what you’re doing before you start. Some plants’ seeds require cold temperatures, other seeds need to be warm. Some even need to be warm, then cold. Some seeds like to be cool and moist, others warm and moist!
As Always, Learn
If you’re interested in the growth or reproductive cycles of pine tree or of any plants, do your research. Find credible, academic sources (even reference books, which do still exist), and work to understand the biology and botany.
If you just want to grow a pine tree, find a species that is suited (ideally native) to your local area and specific location, learn all about it, and get planting. I wrote an article on where pine trees grow that would be worth reading if you do want to grow a pine tree.
Featured Image by FlackJacket2010 at Flickr
Kira Nash lives with her family in the sunny French countryside amidst bees and swallows. A writer, editor, and artist by trade, she also teaches creative meditation. She’s passionate about nature and ecology and tries to live as green a life as possible. In her spare time, she surfs, reads, and plays with her cats, although not usually all at once. She loves tea a little too much.
Pollination and fertilization | it's... What is pollination and fertilization?
Coniferous - wind-pollinated plants. This means that the pollen is transferred to the ovules by air movement. At first glance, it may seem that everything is very simple and monotonous here, but, as shown by a number of special studies summarized in 1945 by the Irish botanist J. Doyle, conifers have several significantly different types of pollination.
The best known type of pollination is that of the pine. During late spring or early summer, the seed scales in the pine cone move apart somewhat and its inverted ovules are ready to receive pollen. An abundant amount of pollen delivered by the wind falls into the gaps between the seed scales and is retained by what are called stigma extensions of the edge of the micropyle (pollen entrance). In pine these extensions are relatively thin, but in spruce they are usually wider and more succulent. By this time (and sometimes even earlier), the micropyle begins to secrete the so-called “pollination fluid”, which appears on its top in the form of a drop (“pollination drop”). The release of pollinating fluid is typical not only for most conifers (except for Araucaria), but also for cycads, ginkgoes and gnetaceae. It was also characteristic of seed ferns and cordaites. Pollen grains are easily wetted by the pollinating liquid and are quickly immersed in it. Rapid reabsorption of fluid occurs shortly after such immersion, ending in 10 minutes or even sooner. As a result, pollen grains seem to be sucked inward and reach the top of the megasporangium (nucellus), where they germinate.
Thanks to the air sacs, which play the role of a kind of swimming devices, a kind of floats, pollen grains, as they move up the micropylar canal of the reversed pine ovule, always remain oriented with the distal pole down, i.e. towards the nucellus. Due to this, the distal side of the pollen grain comes into direct contact with the surface of the nucellus (the tip of which in pine is somewhat depressed and forms something like a very weak pollen chamber). In this position, the pollen grain easily germinates and forms a pollen tube. After pollination, the seed scales approach each other and remain tightly pressed against each other until the seeds ripen.
A fundamentally similar type of pollination apparently already existed in primitive Paleozoic conifers. In contrast to pine, pollen grains were surrounded by one continuous air sac, which was interrupted only at the distal pole, where there was a shallow furrow. In all likelihood, this air sac played the role of a “float” in them and contributed to the fact that in the pollinating liquid the pollen grain was always oriented with the distal pole down. In the Late Permian genus Ulmania, already mentioned earlier, the pollen grains were equipped with two air sacs, as in modern pine, and the ovules were inverted, which also resembles pine. Thus, already in the Late Permian, lebachia-type air sacs gave way to more specialized air sacs, which occurred as a result of suppression of the proximal part of the primitive vesiculate sac. Of course, intermediate types must have existed between these two types, and, as J. Doyle points out, modern species have such forms. As one such example, he cited pollen grains large-leaved podocarp (Podocarpus macrophyllus), which have a single pouch that completely surrounds the distal part. Podocarp species sometimes have three air sacs, a trait shared with Microstrobos and Microcachrys.
Thus, already in the Late Permian there were conifers with reversed (inverted) ovules and pollen grains with two air sacs. Similar mechanisms of pollination of pine and podocarps originated from them.
In the pine family, the spruce-type pollination mechanism is also characteristic of spruce, except for Oriental spruce (Picea orientalis). This latter differs from pines and most species of spruce in that its young cones are not erect, but hang down. Therefore, the ovules of the Eastern spruce, although reversed in the same way as in all pines, are directed upwards with their micronile. This explains that the stigma function of the micropilar part is expressed in it to a very strong degree, and outgrowths of the edge of the micropyle form two thick succulent wings. Between the wings there is only a narrow passage from which the pollinating fluid protrudes. Due to the fact that the micropyle of the ovule is directed upwards, the size of the air sacs of pollen grains is greatly reduced, which allows them to quickly pass through a narrow passage down to the nucellus. Thus, in Eastern spruce we observe a change in the position of the young cone and the associated enhancement of the stigma function and the reduction of air sacs.
The type of pollination characteristic of Oriental spruce in a more specialized form is observed in two closely related genera - larch and pseudo-hemlock, belonging to the same pine family. In them, the stigma function of the micropylar region becomes of paramount importance, and one of the two lips (lobes) of the micropyle grows and covers the micropylar canal. In contrast to pine and spruce, pseudo-hemlock does not release pollinating fluid and large pollen grains, which are completely devoid of air sacs in both genera, are caught by sticky hairs covering a large stigma lip. The disappearance of air sacs in larch and pseudosugi is explained by the absence of a pollinating liquid, in which they only serve to swim. On the upper side of the large stigma lip, a depression begins to form, into which some of the pollen grains fall. As a result of the subsequent elongation and convergence of both lips, the pollen grains are enclosed in the upper end of the micropylar canal. In larch, pollen grains pass from the micropylar canal to the nucellus, where they germinate. However, it is not entirely clear how this happens, since during pollination the cones retain their upright position and, therefore, pollen grains must rise up the micronile canal to reach the nucellus. It is assumed that in larch there is a delayed release of pollinating fluid inside the already closed ovule, which, after reabsorption, draws pollen grains inside. Pseudo-hemlock, whose young cones do not show geotropic movements and can be in any position, has a slightly more advanced form of pollination. In contrast to larch, pollen grains remain attached to the inner, invaginated surface of the “stigma” and germinate there, releasing a long pollen tube that reaches the nucellus. Thus, in pseudo-hemlock, all the main features associated with the upright position of young cones were lost, namely: the release of pollinating fluid, lateral air sacs of pollen grains, and germination on the nucellus.
It is impossible not to say a few words about the mechanism of pollination of two closely related genera - fir and cedar, which are among the best known conifers. In both of these genera, the excretion of the pollinating fluid is absent, but the pollen grains are still supplied with air sacs, although in Siberian stone pine there is a tendency to reduce them. The micropylar area of the fir, although still fairly symmetrical, becomes an oblique stigma funnel that traps pollen. But pollen grains do not reach the nucellus and do not send a pollen tube to it. Instead, the micropyle itself curves over the nucellus, and the nucellus grows upward, thereby achieving contact with nearby pollen grains. Unlike fir, the geotropic sensitivity of young cones has disappeared in cedar and they are located at right angles to the branch on which they sit, regardless of the location of the branch itself. The micropilar area is very asymmetrical and expanded in the form of a unilateral stigma. The process of pollination itself takes place like that of a fir, i.e., the stigma protrusion bends over the nucellus, and the nucellus pushes up. Thus, as in fir, as a result of coordinated changes in the micropyle and nucellus, pollen grains end up on the pucellus, where they germinate.
Without dwelling on the modifications of the pollination mechanism in other pine genera, let us say a few words about the pollination of some other conifers. Unfortunately, their pollination has been studied even less than that of pines, and our information is therefore very scarce. Relatively well studied pollination in Araucariaceae, which is of exceptionally great biological interest. In both genera of Araucariaceae - Agatis and Araucaria - pollen grains devoid of air sacs germinate, as it is not unexpected, not on the ovule, but on the seed scale or in its sinus. The pollen tube branches, and some of its branches grow into the tissue of the seed scale; some of the branches of the pollen tube even penetrate the conductive tissue (phloem and xylem) of the cone axis. The pollen tube grows towards the reversed ovule, reaches the top of the nucellus and penetrates into it. So, despite the fact that the Araucariaceae family has retained many archaic features, the pollination mechanism is characterized by high specialization in it and strongly deviates from the original forms of pollination in conifers.
In all other coniferous families, the excretion of a pollinating drop is retained, but pollen grains have retained their air sacs only in the Podocarp family (with the exception of the Saxegothea genus). There is great diversity in the pollination details of different families and even genera of conifers, which opens up an interesting field for further research.
After a certain time after pollination, the fertilization process begins, which usually takes place during the same season. A very special picture is observed in pine species, where 12 to 14 months pass between pollination and fertilization.
Fertilization begins with the formation and growth of a pollen tube that actively works its way through the tissues of the megasnorapgium (nucellus) towards the archegonium. Approximately a week before the act of fertilization, the nucleus of the spermatogenic cell divides, forming two identical or unequal in size (in araucaria and pine) male gametes. The tip of the pollen tube makes its way between the cervical cells of the archegonium and reaches the egg. Here it ruptures, releasing male gametes into the cytoplasm of the egg. Following this, one of the two male gametes enters the egg. The fusion of the two nuclei is very slow, but eventually they fuse to form the first diploid sporophyte nucleus.
Plant life: in 6 volumes. — M.: Enlightenment. Under the editorship of A. L. Takhtadzhyan, editor-in-chief corr. USSR Academy of Sciences, prof. A.A. Fedorov. 1974.
Scotch pine | Company LESSHOP
Scotch pine is considered a fairly common tree species, however, it does not grow everywhere. In particular, pine cannot be found in the upper part of the forest belt of the mountains of the Baikal Range, the Eastern Sayan, Khamar-Daban, the North Baikal and Patom Highlands. This is due to the fact that Scots pine, although it is considered a fast-growing tree species, is not able to grow in areas with a cold, harsh climate, in areas where dark coniferous trees are more common.
Pine is not particularly demanding on the composition and moisture of soils, like other conifers, and can grow on a wide variety of soils. Pine as a tree species is divided into a large number of species and types. In particular, on the soils of the Siberian region, Siberian pine is most common, which differs from other types of pine in a special shape of cones.
Pine is considered a fairly large tree species. Its height can reach 55 meters, and the diameter of the trunk is about one and a half meters. A tree lives on average about 500 years. Of course. This is possible only if the conditions in which the tree grows are favorable. Pine is a monoecious tree, with a predominance of flowers of the same sex. Thus, one tree contains predominantly female flowers located at the ends of the shoots and having the shape of small cones, the other tree, in turn, has male inflorescences, which are located closer to the base of the shoots. The predominance of inflorescences of one sex or another is considered a hereditary factor, however, depending on the growing conditions of the tree, or in the presence of any economic influences, the "sex" of the tree may change. The flowering period of pine falls at the end of May - beginning of June, when the air temperature is already quite high. Pollination occurs through the wind. At the same time, fertilization of seeds can be expected only next year.
In pine forests, during the period of pine pollination, one can notice the appearance of a yellow coating on the soil surface. It's pine pollen. In general, pine is characterized by fairly good pollination. What became possible due to the fact that tree pollen has air sacs, and therefore can be easily carried by the wind over fairly long distances. The timing of pollination depends on weather conditions, in particular, on clear sunny days, pollen scatters within 3-4 days, in rainy weather this process takes a little longer.
Pine seeds ripen by September of the following year after pollination. At the same time, the seeds remain inside the cones all winter, starting to spread only in April, when the air temperature reaches +10 degrees. It should be noted that for the opening of cones, not so much the temperature of the surrounding air as its humidity is important. Therefore, in some regions, seeds begin to spread somewhat earlier.
Pine seed ripening occurs at different ages, depending on the conditions in which the tree grows. So, free-standing trees can bring seeds already at the age of 10-15 years, and trees growing in plantations where dense crown density is observed - a little later, at 25-30 years. The number of cones and their location depend on the "sex" of the tree. For example, male cones are arranged separately from each other, while female cones tend to form clusters with up to 15 cones.
Scotch pine is considered a light-loving tree species. At the same time, the need for pine in sunlight changes with age. So, in the first years of life, the pine is the most shade-tolerant. In addition, the photophile is influenced, in addition to the age of the tree, by a number of other factors. In particular, this is the degree of moisture in the soil on which the tree grows. Conditions in regions with sufficiently moist soil are considered more favorable for pine, and trees that grow on dry and nutrient-poor soil look more oppressed.
Pine has a fairly plastic root system, which allows it to grow on almost any soil cover. It is important to remember that the growth of the root system of a tree begins at a temperature of +3 degrees, while for other conifers this figure is somewhat lower. So, the spruce root system begins its growth at a temperature of 0 degrees, and the Gmelin larch - at -0.3 degrees.
In the regions of the Krasnoyarsk Territory and the Irkutsk Region, Scots pine is unevenly distributed. It depends on the quality of the soil, as well as on the degree of its freezing. So, in the southwestern and western parts of the region, where the soil does not freeze through. Pine creates a deep and strong root system, which makes the tree resistant to winds. In the region of the Middle Angara region with its clayey and frozen soils, the pine has a shallow root system, such a tree is considered windfall. In the area of the Lena River, the pine root system quickly grows in sandy soil, so the pine is stable here.
The conditions in which pine grows are greatly influenced by the state of soil water. The fact is that the pine root system is very sensitive to this factor, and a significant decrease or increase in the level of soil water can lead to the drying out of pine forests. This sensitivity develops with age. Thus, trees over 100 years old are considered more sensitive to groundwater levels than younger pines.
Pine wood is considered quite dense, sound, with a high content of wood resin. In young trees, the wood is straight-layered, turning into a cross-layered with age. The density of wood and its mechanical properties, which are paid attention in construction, are influenced by a number of factors, in particular, the moisture content of the soils on which the tree grew. So, pine, growing on dry, poorly moist soils, has a denser and more resistant to damage wood. Conversely, a tree growing in moist soil has a less dense wood with poorer mechanical performance.
Where is pine used?
Pine wood contains much more resin than other conifers. That is why pine is widely used to obtain resins by tapping. At the same time, resin is obtained not only from living trees, but also from pine stumps (rosin, extraction turpentine).
Pine wood is widely used in the construction, furniture industry, for the production of containers, in the paper and pulp industry, and in many other industries. That is why pine is so valued today.
Pine needles are rich in various kinds of vitamins, which is why products based on it are widely used as vitamin supplements for farm animals. Pine needles are also used to create special therapeutic and vitamin pastes used for medical purposes. The equipment intended for the production of these products was invented several decades ago by domestic inventors, however, for a number of reasons, these installations have not received much distribution in our country.
It is noticed that most of the sanatoriums are located in pine forests. And this is no accident. The fact is that pine releases into the air a large amount of phytoncides, substances that destroy harmful bacteria and viruses, which makes it healing.
Pine planting is also used for other purposes. For example, a kind of two-tiered pine root system allows you to save the sands of nearby soils from dispersal, ensure optimal soil moisture, and save ravines and cliffs from sprinkling.