This week, Apple announced the impending release of the iPad 2. If this device sells anything like the first one, hundreds of thousands of iPads could be in peoples' hands by this time next month. And not long after that, thousands of first-generation iPads could be on their way to new owners.

 
There are a number of eco-friendly apps available for the iPad that can help reduce your impact on the planet — or at least make you appreciate nature more than you already do.
 
Here are five green apps worth checking out:
 
1. Audubon's Mobile Guides: These apps offer digital versions of Audubon's famous field guilds for birds, mammals, wildflowers, butterflies and a whole lot more. There are six apps for North American species, plus two more that roll several of the smaller apps into one big app. ($4.99 to $29.99)
 
2. iGrowIt: The iGrowIt app will not only explain which vegetables will grow best in your area, but what time of the year to plant them and the best ways to help them thrive. (Oh, and it includes healthy recipes, too.) The Sunday Times recently called this one of the best 500 apps in the world, but recent user reviews warn that it may crash on the iPad, so be aware of that possible bug. ($0.99)
 
3. Netflix: The movies-by-mail company is changing again, delivering movies online with no physical disks going back and forth by mail. That saves time and greenhouse gases, which are emitted during all that shipping to and fro. This app lets you search the complete Netflix database for films to watch instantly, although you can no longer add physical disks to your mail queue through the app. (Free, plus Netflix subscription fees)
 
4. EcoDice: This is a light but fun app that lets you spin a special set of dice on your iPad, then gives you an eco-friendly task to do that day. Options include walk or take a bicycle to work for the day, unplug a device that's on standby power, or share your shower with a friend. The same company also has similar dice apps for kindness and wellness. ($0.99)
 
5. Green Planet 4 Kids. Here's a fun one for the whole family. Based on the Web site of the same name, Green Planet 4 Kids is a book-like app that features a dinosaur family learning how to make green choices about water, electricity, transportation and heating, among other options. (Free)
 
What are your favorite green iPad apps? Let us know in the comments section below.