Flower Phenology Through April

May 5, 2010 at 3:45 am (botany, ecology, Uncategorized)
Tags: Anemone quinquefolia, Malus floribunda, Malus prunifolia, Mayslake, phenology, plum-leaved crab, Viola pubescens, wood anemone, yellow violet

by Carl Strang

Last year I started a study of flower phenology at Mayslake Forest Preserve. I recorded the date on which I saw the first open flowers of each species. This year I have been doing the same, and am in a position to compare the years. For instance, yellow violets first bloomed on May 4 in 2009, April 19 this year, 15 days earlier.

Wood anemones flowered 19 days earlier.

I still had not sorted out the woody members of the rose family last year, so I could not record a difference for some of the non-native species. These include plum-leaved crab, which first opened flowers on April 19.

There are also a few brilliantly colored crabs which may be Malus floribunda.

Altogether, I have first flower dates for 28 species at Mayslake to compare between years. In only one case did a plant bloom later (by only one day) in 2010. The difference in dates was in double digits for all but 5 plants. The median difference was 13 days earlier in 2010. Though months are somewhat artificial, they do provide convenient blocks through which to follow phenology differences through the seasons.