56 A number of unsuccessful introductions were attempted by the colonists during the 1930's (Rodman, 1935; Colonists' Daily Log, 1936). These are listed as follows: Calocasia esculenta, Brassica oleracea, Brassica rapa, Beta vulgaris, Solanum tuberosum, Ipomoea batatas, Daucus carota, Allium sp., Citrus sp., and Sida sp. (probably cordifolia). Vegetation History Early accounts give meager information concerning the natural vegetation of Baker Island prior to the guano mining activities which according to Hutchinson (1950) removed between 250,000 and 300,000 tons of surface materials. The earliest account (Hague, 1862) describes the marginal sandy ridge as "partially covered with a rank growth of long, coarse grass (Lepturus), portulaca (Portulaca lutea), mesembryanthemum (Sesuvium) and a few other species of plants." The same author noted that "none of the grass that grows abundantly on the margin is found on the guano, but there are one or two species of portulaca occurring in certain parts, (particularly where the guano is shallowest and driest)..." This account clearly designates two plant associations. The first refers to a Lepturus association confined to the sandy margins of the island, and the second to a Portulaca association found on guano soils in the interior. Sesuvium is recorded from the marginal sand ridge. Although this species appears more common and vigorous on the lagoon margins over hardpans this author has found it in sand on both Enderbury and Birnie Islands. The plants observed by Hague may represent remnant populations of a former lagoon mat. Another early history (Emerson, 1869) offers a record of other native species. Emerson states that the island "...has enough soil to support a stunted vegetation. This consists of a coarse grass, used for thatching tuts (Lepturus or possibly the introduced Digitaria); a hardy species of parsley (Apium petroselinum); a woody bush with pretty yellow flowers called by the Hawaiian's I-li-ma (Sida fallax); a plant which has a tuberous root, resembling a four o'clock (possibly Boerhavia)...and a vine bearing fragrant yellow flowers and troublesome thorns that are shaped like caltrops (Tribulus)." Surveys of Baker Island were reported on by Christophersen (1927) and Bryan (1942). The latter author mentions sixteen species of plants observing that Lepturus is found in approximately the same area as that mentioned by Hague. Bryan also observed that Digitaria was found on the inner flat from which the guano had been removed. This is approximately equivalent to the distribution of the heaviest stands of these two grass species in 1964. During the 1930's a number of species were cultivated by the colonists but most were lost to rats and crabs (Rodman, 1935; Colonists' Daily Log, 1936). This account points up the possibly important role of hermit crabs as regards the success of seeding plants which germinate after the infrequent rains. During World War II Baker Island was used as a staging point for the invasion of the Gilbert Islands (Anon., 1943). Grading and laying of an airstrip was completed in September 1943. The displacement of the surface soil layers of Baker Island has taken place from the nineteenth century guano mining operations through the Second World War runway and building construction (in excess of 2000 men were housed on the island).