SSION
aluate the recove
ry and
t the Eniwetok Pr
ovin
fifteen months aft
er
vere made in 1949
by
LPH. They repo
rted
ities in ten Specie
s of
i where atomic de
tonaand where radiat
ion
higher than those
on
Nectar survey. Th
ese
lattening, shorteni
ng
‘sion of stems,
severe
nd stems, chloro
sis,
umpling and twis
ting
‘ms, proliferation an
d
aces, abnormal pr
o-
Table 1. The regrowth ofScaevola sp. (Plant No. 1319) at Belle Island, Entwetok Atoll,from May 22, 1954 to March 15,
1955 following the detonation of May 14, 195+ at a site two and one-half miles away
Date
4/15/54
Healthy; green flowers and
fruits present
5/22
Plant badly damaged,
stems naked and broken;
some burned and green
leaves persist at terminals
6/19
8/12
ng and splitting of
9/14
Imson Aitsu (Oli
ve)
etween two of th
e
he plants closest
to
lere radiation lev
els
verely affected. In
Is were lower, th
e
habitats” was re-
in excluding plants
liation effects fr
om
Y Many of the
" growth after the
9cCurred in jm
inmic nutrients an
d
ons are known to
ch can sometimes
€ of the plant, In
tas been remove
d
the surface layer
g in the curling,
€ shallow-rooted
‘ervations it may
€ abnormalities
ased by factors
€, It would be
the causes of
vhere radiation
ast. In areas of
F this damage
|
Appearance
11/2
11/30
3/15/55
New leaves on stems;
branchesstill scrawnylooking
Most leaves green and
healthy; plant not as bushy
as in April
| Length of |
Over-all ©
larger
|
|
Height
|
(cm)
diameter
75
90
|
erility of plants. St.
mutant of Guetta
rdg
t did not describe
It.
187
R. F. PALUMBO
OLL
(cm)
,
leaves
(cm)
16
A few plants observed
|
|
|
with persistent floral
45
+0
|
|
75
65
No flowers observed on
on this plant
15
|
79
75
Plant as healthy and bushy
as in April
75
90
Growth normal in every.
respect; small flowers
present
75
90
~=—20
Plants healthy, larger than
in April, many Howers
78
95
20
Yellowing of oldest leaves
only; plant healthy, no
flowers or fruits
parts
75
|
|
:
Remarks
|;
16
|
|
|
20
'
‘
Flowers
present
on
Seaevola Plant No. 1209,
Area C
Flowers present
on
Scaevola Plants No. 1209
and No. 1213, Area A,
and others
Some Scaevola plants 2
100
could be attributed to the radiation, becauseit
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
can cause plant abnormalities of various
kinds,@®) similar to those found at the Eniwetok
1
125
20
metres in height
Observations made in February 1956 in the
Marshall Islands by FosBerc®!% 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,
dose
Suriana maritima and others) at Gegen Island,
conifers Sparrow? observed that doses as low
dose to infinity’? was reported to be 3,360 r.
Whioere the levels of radiation were 10-100 times
Proving Ground.
The
total
gamma
delivered in these experiments ranged from
780 r to 5,550 r. In more recent studies with
as 3 r 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.
Rongelap Atoll, where the “‘total radiation
lower, little or no damage was observed. How-
ever, some species (Guettarda, Lepturus repens, and
Fleurya ruderalis) appeared to be normal at
Kabelle Island where the radiation level was
high (total dose 1,824 r). Other species (Surzana,
Cordia
subcordata,
Cocos
nucifera
and
Pisonia