| Observations have been made at Pleasant
Valley Conservancy of the growth, flowering, and seed set for many
plant species. The table below gives the averages for 126 species
for the years 2002 through 2005. Included in this table are prairie,
savanna, and woodland species. Weeds and nonnative species are not
included.
The plants are arranged in this table by the time of first flowering,
since this is the time when each species is most readily visible.
The species listed are only those that are present at Pleasant Valley
Conservancy, but include most of the common prairie, savanna, and
woodland species to be found at other locations in southern Wisconsin.
Phenology of the vegetative state Although the
species are arranged by time of first flowering, data are also given
on the times when the plants were first observed in the vegetative
state. The column "1st leaves" gives dates when the first
recognizable leaves have been seen. These dates are very useful
because they give early seasonal clues to the success of restoration
work. However, not all species are easily recognized in the vegetative
state. The leaves of some species are not very distinctive, so that
a positive identification is not possible. To recognize a plant
in the vegetative state, it helps a lot to know where it is likely
to grow, and when. The leaves of some plants (prairie dock and compass
plant) are so characteristic that a positive identification is easy.
For others, considerable field experience is necessary. When in
doubt, mark the plant and return when it is in flower.
Phenology of flower bud formation Although the
species are arranged by time of first flowering, many species can
be recognized much earlier because of their distinctive flower buds.
The column giving these dates may thus be helpful.
Phenology of flowering Flowering times vary from
year to year, and also from site to site. Thus, the times in this
table are only approximate. Some species flower over only a very
short duration, whereas others flower over a much longer period
of the growing season. No single specimen of a species will flower
for a long time, but different specimens, either in the same location
or at different locations, may flower early while others flower
late. Examples of species that flower over a long period of time
are black-eyed susan and ox-eye sunflower.
Phenology of seed set Some species set ripe seed
soon after they are finished flowering, whereas seeds of others
take much longer to ripen. Some species hold their seeds for long
periods of time, so that seed collecting is easy, whereas other
species drop their seeds soon after they are ripe. The data in the
table give a rough approximation of the phenology of seed set. Also
given are approximate dates when ripe seed can be collected. Follow
this link for more extensive data on seed collecting dates.
Those species whose seeds are held in pods are
listed in the Comments column. Since the seeds are ripening inside
pods, it is difficult to determine when they are ready to collect.
The collecting dates given in the table are only approximate but
may be helpful. Also given are the last dates at which seeds can
be collected. Again, these dates are only approximate. |
