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1900
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Days after i4 May (954
Fic. 3. Gammadoserates at three feet at Belle Island, Eniwetok Atoll, May 15, 1954 to
March 21, 1955, compared with the decay of fission products from the slow neutron
fission of U2352),
16
looking. A photograph of the general area taken
at this time (Fig. 4a) shows the healthy appearance of the vegetation. In some plants there was
yellowing of the leaves and necrosis, especially
in Scaevola and Guettarda, and some reddening
of the tops of the grass, Lepturus repens. The latter
symptom is typical of some species of plants
growing in phosphorus-deficientsoil, a condition
often found on coralatolls and in areas where the
top soil has been disturbed or blown away. The
Mike detonation of 1952 had removed most of
the plants and top soil from Belle Island, result-
ing in the depletion of some of the elements
essential for plant growth. In spite of these
deficiencies regrowth of the plants at Belle
Island was rapid. In April 1954 some of the
Scaevola and Messerschmidia ‘trees’? were up to
plant
1955,
five feet in height, with a spread of ten feet, and
bore many flowers and fruits. Plants of the other
species also were well established.
A photographofBelle Island taken eight days
following the Nectar detonation (Fig. 4b) shows
the extent of the damagesustained bythe plants.
From the air the island looked brown and
desolate. On closer inspection it was found that
most of the plants had been scorched by the
heat wave and many of them had been blown
over or broken by the shock blast. Two of the
previously tagged plants (Cocos and Portulaca)
had disappeared or had been dislodged from
their original positions; other plants of these
species were staked and labelled for study. On
the tall shrubs, such as Scaevola, Messerschmidia
and Guettarda, the leaves were usually gone or
scorched, and the scorched branches and a few
persistent leaves were all that remained of the
plants. Flowers and fruits were found on some
plants, especially in the prostrate plants such as
Portulaca, which was located behind a large
fallen coconut trunk. Close-ups of examples of
damaged plants eight days post Nectar are
shown in the foreground of Figures 4b and 5a.
Recovery of the plants was rapid. Heavy
rains occurred on the third day. On the eighth
day green buds, 1-3 mm in length, were observed on the stems of Scaevola and .VMesser-