Flowering Phenology Season Summary

by Carl Strang

We are experiencing the final gaudy show of asters and goldenrods, but this year’s flowering season is coming to an end. Occasionally I find a new plant to add to the Mayslake Forest Preserve species list, the most recent being velvetleaf.

However, the time has come for the final tally comparing first flowering dates of species that I observed in both 2009 and 2010. If I limit the data to the 78 species for which I have reasonably firm first flowering dates this year, the median is 12 days earlier than 2009. If I include all 174 species, throwing in those whose flowering was well underway when I noted them this year, the median is 7 days earlier. Ranges for firm-date species were 38 days earlier to 21 days later than in 2009. Overall ranges were 38 days earlier to 43 days later. This result supports the impression that 2009 was an unusually cool year, with all the cascading ecological effects on plants, insects and other species. Future years’ data will add more context, and will allow me to look for patterns shown by individual species at Mayslake.



  1. nellie said,

    October 8, 2010 at 9:18 pm

    So very interesting and it is good to have hard data to back up so many people’s anecdotal conclusions.

  2. Sally said,

    January 21, 2011 at 1:24 pm

    Just discovered your site, Carl– great stuff here. I took the liberty of sending the “Vines” post to the host of this month’s upcoming Berry-Go-Round plant carnival. This post, with its phenological data, would be great too.

    Your insect posts are fascinating, but I’ll be hoping for more of these great plant posts. (I even like the template…) Will be back for more visits.

    • natureinquiries said,

      January 24, 2011 at 7:13 am

      Thanks, Sally,
      The template is not my design; I chose it from those available through the WordPress host.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: