Hi Jenny. i really like the composition of this one, but the sky at the top is completely blown out, as are the tops of the cactus. The focus could be just a tad sharper. If you are using an autofocus try setting your focus with the camera pointed at the sky - this will properly expose the sky and eliminate the blown out look. Take several pictures of the same composition with various exposure settings to see which provides the best overall look.
A+ for effort, again, the composition is very nice and a great concept, just a few technical things that could be a bit cleaner.
"'Life is not a journey to the grave with the
intention of arriving safely in a pretty
and well preserved body,
but rather to skid in broadside,
thoroughly used up,
totally worn out,
and loudly proclaiming,
"WOW! What a ride!"'
It's a great picture, I love how you captured the sun in the spines of the cacti. The second hill in the distance seems a bit excessive to me, but I like simpler images that have more meaning in the small things :).