Bulletin - United States National Museum - Smithsonian Institution

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FLORA OF WASHINGTON AND VICINITY, 27
spring. There are a few plants which may sometimes be found in flower
here in January, such as Siellaria media, Taraxaciim Dens-leonis, or Acer
dasycarpum (collected January 17, 1876, in the city), in favored places;
but these will bloom at any time when a few days of mild weather with
sunshine can come to revive them. There are, however, several strictly
vernal species, which bloom quite regularly in the latter part of Feb-
ruary, such as Symplocarpus fcetidus, Chrysosplenium Americanum, and
often Anemojie Hepatica. The number regularly found in flower in March
is quite large, and in special years very large. It was, of course, im-
possible to make observations every day of any year, but taking a num-
ber of years, my observations cover nearly every day of the spring
season. As showing the number of these early vernal species, and also
how widely the seasons may differ, the following facts are presented
In the year 1878, 17 species had actually been seen in flower and noted
up to March 24. I did not go out again that year until April 7, when I
enumerated 46 additional species, making 63 in all up to that date. This
was an exceptionally early season. The next spring—that of 1879—was
a backward one, as is shown by the fact that, while I had visited the
same localities and taken notes with equal care, only 33 species had
been seen in flower up to Ai)ril 13. Twenty-nine species which had been
seen in flower on April 7, 1878, were not yet in flower in the same locali-
ties on April 13, 1879. There appeared to be about three weeks' differ-
ence in these two seasons. The last season—1880—was again an early
one, though less so than 1878. It was, however, near enough to the
average to render the facts observed of great value. The following are
a few of them
On February 29, seven species were seen in flower in the Eock Creek
Region. On Aj^ril 4, thirty were enumerated on the Virginia side of the
Potomac, above the Aqueduct Bridge. On April 11, eleven were seen in
addition to those previously enumerated in the Eastern Branch region;
and on the 18th of April, High Island was visited and twenty-nine added
to all previously recorded, three of which were then in fruit. The total
to this date was, therefore, seventy species. This season I concluded was
a week or ten days later than that of 1878, and as much earlier than
that of 1879.*
We may now inquire what some of these early plants are.
* Since the above was written, the present season (1881) has passed its vernal period.
It has proved still more backward than 1879 and the latest spring thus far observed.
On April 3 I made my first excursion and visited the Virginia side of the Potomac
above Rosslyn. Only 7 species were seen in flower, including Alnus serrulata, which
doubtless can be obtained much earlier in ordinary years, but has been overlooked.
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