Phenology data is extremely useful as it links plant and animal behaviors to seasonal climate and weather patterns. Climate scientists are using Thoreau's detailed notes on plant phenology in studies of changes in climate in the last 150 years.

As a more mundane use of phenology data, how one plant species responds to weather patterns is likely to tell you something about another plant species in the same general area. If you are doing plant surveys for one species that requires flower or fruit characteristics for positive ID, and it's in an out-of-the way location, knowing that another species with similar phenology has not bloomed yet, or is past bloom, can help you avoid going out of your way to look for a plant only to find that it hasn't bloomed yet or you are too late. It can also help compensate for year-to-year differences in weather patterns: if it's been a cooler spring, then plants may bloom later.

If you have internet access, consider using Twitter to exchange phenology information. Twitter is a free online service for exchanging very short messages (140 characters or less) known as "tweets" -- okay, so the hi-tech world is a little bit weird when it comes to giving things names. You can access Twitter from the World Wide Web or from cell phones with text messaging. Here's an example from the NHbotany twitter page I maintain:

NHbotany #phenology Corylus cornuta 4/18/2009 Goffstown NH http://tinyurl.com/cvwd8d

I've included a few things here:

• #phenology -- the "#" symbol is a Twitter convention for a topic.
• Corylus cornuta -- the botanical name for beaked hazelnut (in my back yard)
• 4/18/2009 -- the date of the observation (in case you see something and don't post on Twitter until a few days later)
• Goffstown NH -- the town and state (please don't be more specific than that!)
• http://tinyurl.com/cvwd8d -- in this case I wanted to include a link to a photograph I took. I posted my photograph on my Flickr account, and added the link to my "tweet". Twitter automatically converted it to a tinyurl link but you can do that yourself on http://tinyurl.com/ which is a website that creates short "permalinks" to websites with a longer URL. You can also post photographs on http://twitpic.com/ which some people on Twitter use. I'm probably not going to post photographs in all cases but it seemed appropriate for the first one, especially in that early stage of spring where we're all getting cabin fever. If I didn't post a photograph, I would mention something short like "flowering" or "fruiting" or something.

Twitter also has a search page. I can search for #phenology by going to http://search.twitter.com/ and typing it in, or I can just bookmark the page http://search.twitter.com/search?q=%23phenology if I want a quick shortcut. (The %23 stands for the # sign) There are a few other people in various parts of the country, so searching for #phenology NH (http://search.twitter.com/search?q=%23phenology+NH) brings up only the "tweets" that have #phenology and NH in them.
Here's hoping this is a useful tool for plant hunters!