| 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 a four-year
period. 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 this list includes 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. |