Why do leaves change color during this time of year?
915298
The leaves don't exactly "change color."\nThe yellow, red, and brown pigments are there all year long, but are masked by chlorophyll the while the leaves are “alive.” Chlorophyll, made up of tiny green sacks called chloroplasts, is the green photosynthetic chemical most associated with photosynthesis, the process by which plants turn sunlight in to energy.\nStarting in spring Chlorophyll is produced, used, and replaced inside the leaf, keeping it lush and green. In the fall, when nights get longer and days get colder, trees start packing up shop for the winter by shutting down chlorophyll production and closing off the leaves from the flow of sap.\nLeft trapped inside the leaves are other photosynthetic chemicals know as Carotenoids (yellow, orange, and brown) and  Anthocyanins (reds, purples, royal blue). Just like with paints, varying how much of what pigment is in each leaf varies what colors will be produced. How much of what pigmented chemical is left behind depends on a whole host of environmental and biological factors including how much sugar is trapped in the leaf, the ph of the sap, temperature, length of days, intensity of sunlight, etc.
921099
It is fall, any leaves should have fall off by now anyways. Do not worry about it until spring, on the upside, if you have a decent tree, you will always have flowers to give to your mom!
134329
Leaves look green because they reflect green light. So at this, and nearby, wavelengths very little light energy is used to synthesise sugars (& starch).\nThe most effective wavelengths are therefore at the 'red end' of the spectrum or the 'blue end'. As it happens it is light at the 'red end' that is most important.\n\nThis info. would make a nice line graph - you could look up either absorption spectrum or action spectrum to get a precise answer for your question.
16591
During winter, there is not enough light or water for photosynthesis. The trees will rest, and live off the food they stored during the summer. They begin to shut down their food-making factories. The green chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange colors. Small amounts of these colors have been in the leaves all along. We just can't see them in the summer, because they are covered up by the green chlorophyll. \n\nThe bright reds and purples we see in leaves are made mostly in the fall. In some trees, like maples, glucose is trapped in the leaves after photosynthesis stops. Sunlight and the cool nights of autumn cause the leaves turn this glucose into a red color. The brown color of trees like oaks is made from wastes left in the leaves. \n\nIt is the combination of all these things that make the beautiful colors we enjoy in the fall. \n\n\n\n\nhttp://www.sciencemadesimple.com/leaves.html\n\nGOOD LUCK\n\nParadiso
209024
yes. It is due to the number of hours of daylight or darkness. During spring, plants flower because there is so many hours of daylight
218041
It is quite true that soil temperatures where the living parts of the plants are during winter are not as cold as the surface temperature. That is the first fact. The second thing that comes into play is that plants produce chemicals that depress the freezing point of water and prevent ice crystals from forming and rupturing cell walls. The next factor is that many plants forms seeds or spores that are biologically inactive when conditions are not suitable for growth. This is sort of a suspended animation. It is also important to recall that plants even as large as trees have only a very small proportion of actual "living material." In a tree in winter, the cambium and rootas are "alive" The cambium goes inactive and reactivates when spring comes and the roots remain fairly dormant through winter until warming weather stimulates the cambium back to life and the roots then beginning sending sap up the tree. The question is complex as plants vary from one celled organisms to trees.
1058175
Flowers which change color often do so based upon the acid or base content of the soil.\n\nThis might be the situation in your case.
798758
Seasons reasons \nUnless you live near the Earth's equator, you have no doubt noticed that the weather changes during the year: it is hotter during the Summer, colder in Winter, and somewhere in between during Spring and Fall. These are the seasons, a regular change in temperature, that repeat themselves every year, more or less regularly. \n\nWhat causes these changes? The Sun is our main source of heat, and since these changes are the same every year, it surely has something to do with the movement of the Earth around the Sun. If we get closer to a fire, we get hotter. Could it be then that the Earth gets closer to the Sun during Summer, and farther during Winter?  This idea seems at first to have some merit, until we remember that the seasons get reversed when we cross the equator: when it is Summer in the northern hemisphere, it is Winter in the southern one, and vice versa. And surely Argentina is at the same distance from the Sun as the USA! \n\nBesides, that the Earth's orbit is an ellipse, not a circle, so that at some times the Earth is closer to the Sun than at others; but this ellipse is very nearly a circle, and the relatively small differences in distance to the Sun cannot account for the changes in temperature. And to make things worse, the Earth is closer to the Sun during the northern hemisphere Winter! \n\nWhat, then, is, the cause of the seasons? \n\n\n\nIn the above animation, you can see the Earth during one full year (the animation then starts over again), as you would if you looked straight at it from the Sun. As you can see, the part of the Earth that is directly facing the sun changes with the time of the year. It is the northern half for a while, then moves south of the equator, only to move back to the north again. \n\nWhat causes this? The Earth rotates around an imaginary line passing through the poles, called the axis. This line forms an angle (called the tilt) of 23.4° with the perpendicular to the orbit of the Earth around the Sun. \n\n\n\n\nAs the Earth moves around the Sun, this axis stays always pointing in the same direction. This means that, during part of the year, the northern part of the Earth will lean more directly against the sun, and during other parts the southern part will. \n\n What has this to do with temperature? Well, when the northern hemisphere is leaning away from the sun, the rays coming from it hit this part of the Earth at a smaller angle than on other parts of the world. This means that the same amount of light is distributed over a larger surface, and therefore these places receive less heat than the others. The southern hemisphere is experiencing Summer, the northern hemisphere Winter. In half a year, the situation reverses, and it is now Winter in the southern hemisphere since that part of the earth is now leaning away from the sun. \n\nThe seasons are then the result of this tilt of the Earth's axis. If the tilt of the Earth's axis was 0° there would be no difference in how the rays from the sun hit its different regions, and there would be no seasons. \n\nNot all planets have the same kind of tilt as the Earth has: Uranus, for example, has a tilt of almost 98°. Its axis, then, lies almost on the plane of its orbit, and a day there lasts about as much as one year on Uranus: about 84 Earth-years.
816928
Autumn is a second spring when every leaf is a flower. \n\nFiery colors have begun their yearly conquest of the hills.\n\nOne kind word can warm three winter months. \n\nNo shade, no shine, no butterflies, no bees,\nNo fruits, no flowers, no leaves, no birds—November\n\nBare November\n\nThirty days hath September, April, June and November
887479
since plants are mainly composed of chlorophyll and chlorophyll is green then the plants tend to be green. but they also have other colors such as red or yellow. thats why when trees shed their leaves in the fall what they are really doing is killing off the chlorophyll allowing the other colors to come out and be noticed.
838815
its fall time all leaves are falling off. if ur tree doesnt re-sprout leaves in spring that could be a problem. use fertilizers and place it in a place where its not very cold.
864820
Depends on the plant species.  Some trees shed their leaves in fall and don't grow them back until the next spring.  Anyway you're thinking wayyyyyyyyy too much about plants at a lunar base.  Anything brought there would most likely be stuck under some kind lamp to simulate light conditions on the earth, so your problem is moot.
53581
Autumn, because of the richness of the colors. I love the oranges, reds, yellows, and browns of the leaves turning...the crunch of leaves on the grass...preparing for the holidays...the cooler weather. I'm a "cold weather lover", for sure. The autumn air is fresher, the skies are bluer, and it has good memories for me.
867650
The fall colors are the "natural" color of the leaves.  The same leaves look green during the spring and summer, because they are filled with chlorophyll, which is itself green.  When the tree stops growing in the cooler months, it stops producing chorophyll, which dies off, leaving the reds, oranges and yellows that we see.\n\nHope this helps.  Good luck!!
731024
This is due to the way we perceive objects.  When you look at something and see a color, you are merely seeing color being reflected back at you.  In theory, the sun (or lights in our houses) produce white light which consists of every color.  When white light hits an object, some of it reflects and some of it is absorbed.  In black objects, no light reflects and all of it is absorbed.  In white objects, all the light reflects and none is absorbed.  Similarly, the same is true about colored objects.  In red things, red light reflects and everything else is absorbed.  In blue objects, blue light reflects and everything else is absorbed.  Similarly with plants, the green leaves reflect green light and all the rest of white light (red, blue, orange, purple, etc) is absorbed and used as energy.  Specifically, it is the properties of chlorophyll A and chlorophyll B that cause this green reflection.  Oddly enough, in most plants there is some Betacarotine as well that reflects orange light.  There is just so much more chlorophyll that all we see is green.  However, in the fall when leaves start to die, the chlorophyll goes first and the betacarotine sticks around, causing the leaves to turn orange!\n\nHope this helps!
1085073
As summer ends and autumn comes, the days get shorter and shorter. This is how the trees "know" to begin getting ready for winter.\n\nDuring winter, there is not enough light or water for photosynthesis. The trees will rest, and live off the food they stored during the summer. They begin to shut down their food-making factories. The green chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange colors. Small amounts of these colors have been in the leaves all along. We just can't see them in the summer, because they are covered up by the green chlorophyll.\n\nThe bright reds and purples we see in leaves are made mostly in the fall. In some trees, like maples, glucose is trapped in the leaves after photosynthesis stops. Sunlight and the cool nights of autumn cause the leaves turn this glucose into a red color. The brown color of trees like oaks is made from wastes left in the leaves.\n\nIt is the combination of all these things that make the beautiful colors we enjoy in the fall.
105603
WHY IS THE SUNSET RED?\nAs the sun begins to set, the light must travel farther through the atmosphere before it gets to you. More of the light is reflected and scattered. As less reaches you directly, the sun appears less bright. The color of the sun itself appears to change, first to orange and then to red. This is because even more of the short wavelength blues and greens are now scattered. Only the longer wavelengths are left in the direct beam that reaches your eyes.