SSION
aluate the Tecovery an
d
t the Eniwetok Prov
ing
fifteen months aft
er
vere made in 1949
by
LPH,(®) They rep
orted
ites in ten specie
s of
‘ where atomic deto
naand where radiat
ion
higher than those on
Nectar survey. Th
ese
lattening, shortenin
g,
‘sion of stems,
severe
nd Stems, chlorosis
,
umpling and twisti
ng
“ms, proliferation
and
nees, abnormal pro
erility of plants.
St.
mutant of Guettarda
t did not describe
it.
ng and splitting of
mson Aitsy (Olive
)
xetween two of the
he plants closest to
dere radiation levels
-verely affected.
In
ls were lower,
the
habitats” was re-~
in excluding plants
liation effects from
'y many of the
° growth after the
occurred in im-
anic nutrients an
d
‘ons are known
to
ich can sometimes
ce of the plant. In
has been removed
the surface layer
1g In the curling,
he shallow-rooted
s€rvations it may
he abnormalities
used by factors
re, it would be
f the causes of
where radiation
“xist. In areas of
of this damage
187
R. F. PALUMBO
ILL
Table 1. The regrowth ofScaevola sp. (Plant No. 1319) at Belle Island, Eniwetok Atoll,from May 22, 1954 to March 15,
1955 following the detonation of May 14, 1954 at a site two and one-half miles away
|
}\
Date
|
Appearance
'
|
4/15/54
|
|
5/22
Healthy; green flowers and
fruits present
|
Plant badly damaged,
stems naked and broken;
some burned and green
|
New leaves on stems;
branches still scrawny-
looking
8/12
9/14
11/2
11/30
3/15/55
Most leaves green and
healthy; plant not as bushy
as in April
Plant as healthy and bushy
as in April
Height
75
90
A few plants observed
with
45
40
:
65
|S
75
75
;
1
16
75
90
«=|
20
78
95
100
of various
kinds,“similar to those found at the Eniwetok
total
|
|
gamma dose
delivered in these experiments ranged from
780 r to 5,550 r. In more recent studies with
conifers Sparrow) observed that doses as low
as 3x and 4 r/day caused death of Pinus rigida
after six years of exposure (total cumulative
dose, about 8,000r). Many plants, however,
were dead or dying at doses much below this
cumulated dose, and some visible damage was
observed at doses below 3 r/day.
1
"
125
Flowers present
on
Scaevola Plant No. 1209,
Area C
Flowers
present
on
Scaevola Plants No. 1209
and No. 1213, Area A,
and others
20
20
|
could be attributed to the radiation, because it
has been shown in controlled field experiments,
with several plants, that chronic doses of gamma
radiation of 13-37 r/day for two to five months
The
!
floral
on this plant
|
Yellowing of oldest leaves
Proving Ground.
|
persistent
No flowers observed on
|
7
Plants healthy, larger than
in April, many flowers
abnormalities
parts
75
|
90
plant
Remarks
16
|
75
only; plant healthy, no
]
i
leaves
(cm)
|!
Growth normal in every
respect; small flowers
present
flowers or fruits
can cause
diameter
(cm)
|
(em)
|
leaves persist at terminals
6/19
. Length of
Over-all
larger
|
|
|
Some Scaevola plants 2
20
metres in height
Observations made in February 1956 in the
Marshall Islands by Fosperc®?” also suggest
possible radiation damage to plants twentythree months after an incidence of high-level
radioactive fallout. He found severe damage in
the land plants (Guettarda speciosa, Cocos nuctfera,
Suriana maritima and others) at Gegen Island,
Rongelap Atoll, where the ‘total radiation
dose to infinity” was reported to be 3,360 r.
Wherethelevels of radiation were 10-100 times
lower, little or no damage was observed. How-
ever, some species (Guettarda, Lepturus repens, and
Fleurya ruderatis) appeared to be normal at
Kabelle Island where the radiation level was
high (total dose 1,824 r). Other species (Suriana,
Cordia subcordata, Cocos nucifera and Pisonia