SEED PLANTS OF UPPER LITTORAL BELT 19 
just mentioned, e. g., on the Spit from 480 to 590 west. Of course, the distribu- 
tion of an annual species like this may differ somewhat from year to year, but 
not very widely, since seedlings each year can find suitable space only in the 
areas occupied in the preceding year by their parents or by their, likewise 
annual, competitor, Salicornia europea. The only chance Sueda has of invading 
the more considerable area occupied by its perennial competitors, Spartina 
patens, Distichlis, and Salicornia ambigua, is when these are smothered out by 
flood-trash, or uprooted by fishermen digging on the beach. Such free soil is 
usually promptly appropriated by either Sueda or the annual species of Sal- 
cornia. In those areas on the Spit where Sueda is the dominant species (e. g., 
780 to 820 east, 20 east to 380 west and 480 to 590 west), the band of this plant 
may be from 8 to 12 feet wide. In these stretches the Sueda may be 2 or 3 dm. 
high and stand as thickly as 100 to 200 plants per square meter. In such areas 
there may be only 2 or 3 plants per meter of Atriplex arenaria or Limonium, 
or 5 to 10 plants of Saltcorna europea, to dispute its dominance. From 20 
east to 200 east at 6.5 to 7 feet it nearly equals in quantity the barely dominant 
Salicornia europea, while between 7 and 8 feet it becomes much sparser than 
the latter (plates x111 and xiv). In other areas, e. g., from 20 to 270 east, we 
find a dozen or two plants of Sueda per square meter, scattered through the 
dominant Salicornia europea or S. ambigua. Even in this strip there are short 
stretches where the Sueda is entirely crowded out by these competitors, except 
at the very upper and lower edges of the upper littoral belt. ‘Toward the west 
end of the Spit (800 to 1,000 west), Sueda, often to the number of 8 or 10 
plants per square meter, is scattered, along with occasional plants of Salicorma 
europea, LIimonium, and Atriplex patula, through the dominant Spartina 
Patens. 
Sueda on the Marsh: On the Marsh south of the harbor Sueda is found most 
abundantly on the better-drained parts, such as the edges of ditches or along the 
tide-streams (e. g., 20 north to 30 south by 950 east and 100 south by 1,090 
east). Nowhere on the Marsh, however, does Sueda attain the maximum size 
or density of stand found on the Spit. 
~ On the west shore Sueda has not been seen at all, and on the east side it has 
been found only on the stone pier at 950 north, where it is usually scarce. 
From the examples cited above, which illustrate the more typical areas that 
have been occupied by Sueda during the time our work has been in progress, it 
will be seen that it may grow under the following conditions: It is found on well- 
drained, peaty soil (e. g., on the Marsh), or on relatively thin layers of fine- 
grained mud overlying sand or gravel (e. g., at the upper edge of the Spartina 
glabra on the Spit). Its densest stands, however, are found on the higher levels 
of the upper littoral beach, where the soil is a pretty clear sand or fine gravel. 
Those parts of this beach on the Spit where Sueda occurs over its whole width 
have a sandy or gravelly soil down to the very edge of the Spartina glabra. 
Sueda always grows in well-lighted areas, with no more shade than that fur- 
nished by the small, scattered plants of the Spartina glabra at the upper edge 
of its belt. 
Sueda is not found at any station about the harbor where fresh water is 
present in the soil, or covers the soil, or surrounds the shoot of the plant at any 
stage of the tide. There is no experimental evidence to show what amount 
of exposure to salt water and to air Sueda will endure. The fact that it occurs 
6 
