I have 14 years of professional photographic experience, but all of it Black & White and using an electron microscope! If they were black&white and you threw me in a darkroom with the negatives, I would get em looking brilliant for you

A lot of what I learned is not particularly useful for digital photography in colour, but some of it actually does translate.
With zoom, you have to think about what you need from your final picture. If you are doing them for normal website use, you don't need trillions of pixels worth of detail, sometimes I find I get better focus and results when I stand back further, then crop the picture rather than trying to use the camera zoom. Of course, having a tripod would cut out movement problems, but I have small children to raise who need the money more than the camera shop, sigh, one day.
One final trick which has worked for me both with electron microscopy and with normal photography. Take loads of photos, try a lot of slightly different approaches, and learn to be a really good critic. You wil end up discarding lots, but you are far more likely to get some that really work out right. Fortunately it costs nothing to discard digital photos

Gorgeous trees by the way!