Common Application- Favorite Activity (I participated in Green Team)

Please elaborate on one of your activites (extracurricular, personal activities, or work experience) (150 words or fewer)
A few years ago I believed I was environmentally conscious. I kept my showers under fifteen minutes to conserve water. I recycled milk cartons if I saw the recycle sign printed on the side of the container on the way to the trash. Last summer I participated in Green Team and I realized my prior efforts to help fell short. During the program I cleared brush-covered trails and dug out invasive bittersweet plants. Also, I had the opportunity to listen to speakers lecture about heating using wood chips and the environmental benefits of eating organically. Working with plants on a daily basis and interacting with individuals dedicated to making the planet healthier, I changed my habits. I take shorter showers, recycle used leaves of paper and I am eager to join an organization that performs services to benefit the plant.

and I realized my prior efforts to help fell short
This kind of makes it seem like the efforts were worthless, even though they did help a little. Maybe replace "fell short" with "relatively small" or something like that.

Also, I had the opportunity to listen to speakers lecture about heating
"Speakers lecture" is redundant; the reader knows that there must be a speaker in order for there to be a lecture! Replace with just "lectures"

I take shorter showers, recycle used leaves of paper
Kind of repeating what you started off with; you should just use this once. Maybe think of other habits?
Please read my essay!

A few years ago I believed I was environmentally conscious.
The use of past tense has shown that it happened in the past. If time is not an important part of the activity, keep it as short as possible

I recycled kept milk cartons if until I saw the recycle sign printed on the side of the container recycling bin on the way to the trash.

Keep your sentence short so that you could elaborate on more important thing.

which essay alphacat?

This is the correct verb form to use:
Last summer I participated in Green Team and I realized my prior efforts to help had fallen short.

Last summer you realized that your efforts had been...

This conclusion sentence is not very strong:
I take shorter showers, recycle used leaves of paper and I am eager to join an organization that performs services to benefit the plant.---- it is not strong, because it repeats that "taking short showers" idea from before, as if nothing changed. You can probably come up with a better sentence to express what changed for you.

For you, I recommend reading books by James Lovelock.

You were taking shorter than 15 mins showers - I'm not sure you want to give the impression that even shorter showers constitutes a significant contribution.

A more meaningful concluding sentence (than joining an organization) would help...

This is another version I did. I'm not sure if it's better

I stride down the muddy decline with a shovel slung over my shoulder. The seven members of Green Team follow me carrying pruners and clippers. As I cross the wooden bridge adjacent to the worksite, a tangle of orange vines and a snarl of branches greet me. Eliminating this labyrinth of invasive plants is my task. I am overwhelmed by the myriad of tendrils before me. However, I start rhythmically snipping the intertwined strands and digging them from the moist soil. The more roots I sever and excavate, the more focused I become. I feel as if my efforts will save this forest from the untamed bittersweet plant. When I step away from the project I scan the area that has consumed me for the past hour. The effects of my labor have revealed a small clearing amidst the gigantic mess. I smile to myself and return to the challenge.

This sounds like a poetic way to refer to your environmental protection efforts, too!

This whole thing is great.