Why is the grass green?

Why is the grass green?

[Randy Souza]

You can't delete a question that you asked once it's been answered.

[Daniel Shub]

Wow, I didn't know that. That is a huge improvement.

Answer 1

[Matt J]

Chlorophyll.

This question was really meant as a test. I was planning to delete it.

[Matt J]

Strange. I didn't think it would be possible to Accept ones own answers. Seems like an easy way to cheat and rack up reputation points.

Also strange that you can't delete your own question...

[Daniel Shub]

Low rep users do not get rep for accepting their own answers. I am not sure if when a 500+ rep user accepts an answer one of their own answers for someone else, if they get rep. Further the system might get confused and give them rep if they accept their own answer.

[Matt J]

Hmmm. It's just that on my profile, I'm seeing 4 points for every accepted answer including my own acceptance. A coincidence I guess...

[Daniel Shub]

But you got upvotes (+2 rep) for this and this.

[Matt J]

Interesting that you were able to trace that. My profile shows 0 upvotes for all my Answers.

[Daniel Shub]

It doesn't. The profile view is a little odd and weak. It actually shows that there are 0 up votes on all the questions that you have provided an answer for. The only way to find out what answers you have gotten upvotes for is to look at the answers. Since you only have "only" given 23 answers, I just clicked through them and looked.

[Walter Roberson]

The Recent Activity view lists upvotes, if you have the patience to go through it.

[Walter Roberson]

Saying that grass is green because of chlorophyll has even less explanatory power than saying that Kermit is green because of Miss Piggy.

[Matt J]

"Saying that grass is green because of chlorophyll has even less explanatory power than saying that Kermit is green because of Miss Piggy."

I wouldn't say "less". Unlike Miss Piggy, the green color of grass does originate in chlorophyll. You can obviously go deeper into why chlorophyll is green, I suppose.

[Star Strider]

Chlorophyll Spectrophotometry (Wikipedia)

[Walter Roberson]

https://www.reddit.com/r/askscience/comments/32acyi/why_is_chlorophyll_green_isnt_there_a_more/

"Chlorophyll being green mean is absorbs in the red area of the spectrum. Isn't this low energy light? Wouldn't plants get more energy if they absorbed light in the violet area of the spectrum?"

[Star Strider]

There is more power in the lower frequency region of the spectrum, according to the Wikipedia article on the Spectral composition of sunlight at Earth's surface (link).

[Walter Roberson]

That chart shows increasing power from violet to blue. At close to the upper frequency of blue, it shows a cross-over: up to that point cloud cover does not have much effect, but on higher wavelengths (that is, more towards red) the power increases in direct sunlight and decreases as cloud gets heavier. The hypothesis of blocking excess energy would then suggest that leaves should be red-er to block the higher wavelength energy peaks while being absorbing mid wavelengths that are somewhat constant -- wavelengths in the green range.

The question I quoted as introducing the article was flawed in that it supposed that green means absorbing only in the red and not in the blue or violet, when really it is that green is rejected but red and blue are both absorbed.

An interesting question would be whether the color of plants tends to be different in areas that receive intense sunlight, where it may be more necessary to reject the high power red-er wavelengths that are not blocked by clouds in those areas. I see some hints that in deserts that plants tend to be less intensely green and more blue-gray or yellow -- though that could have to do with pore sizes, perhaps.

Answer 2

[Andreas Goser]

>> why
The green creator wants it so

[Andreas Goser]

Nice. Didn't think of people voting for it :-)

Answer 3

[James Tursa]

Green is waste light. Grass eats the red light and poops the green light.

[Walter Roberson]

Oddly true!

[DGM]

Auugh! I got grass poop in my eyes!