THE AKALA BERRY OF HAWAII 



Asa Gray's Rubus Macraei, an Endemic Hawaiian Raspberry 



J. F. Rock 



Agricultural Explorer, Office of Foreign Seed and Plant Introduction 

 Bureau of Plant Industry, U. S. Department of Agriculture 



THE native Akala of Hawaii (Rubus 

 Macraei, Gray) was first discov- 

 ered by the U. S. Exploring Ex- 

 pedition on the slopes of Mauna Kea, 

 the highest mountain of the Pacific, at 

 an elevation of 6,000 feet. The species 

 was described by Asa Gray in the 

 Botany of that Expedition and was 

 figured in plate 57 accompanying the 

 atlas. 



No mention is made regarding its 

 horticultural possibilities until the time 

 of Hillebrand, who in his Flora of 

 Hawaii on page 116 says, in a footnote: 

 "The species can be recommended for 

 cultivation." It may be stated at the 

 outset that Rubus Macraei is a most 

 variable species and after a close 

 examination of herbarium material and 

 field work it will have to be divided 

 into several varieties if not actual 

 species. 



The Akala berry occurs on several 

 islands of the group, as for example 

 Kauai, Molokai, Maui and Hawaii. 

 On Kauai it is an upright spineless 

 shrub only a few feet in height, with 

 rather small, dry berries. This type 

 was placed by Hillebrand under Rubus 

 Hawaiiensis , with which it has little re- 

 lationship, being of an entirely different 

 habit. It seems that Hillebrand con- 

 fused both species considerably; and 

 the Hawaiian species of Rubus repre- 

 sent another case of confusion such as 

 has been found to exist in the species of 

 Pritchardia, a genus of palms. On 

 Maui the plants resemble, somewhat, 

 the typical species from Hawaii, the 

 type locality, but the plants are 

 exceedingly spiny and the fruits not 

 half the size of those found on Hawaii. 

 It is from the Maui species, especially 

 those coming from the much frequented 

 slopes of Haleakala, that seeds were 

 usually collected and sent to experi- 



menters. Rubus Macraei finds its 

 best development on the slopes of the 

 high mountains of Hawaii proper — on 

 Hualalai, Mauna Loa and Mauna Kea. 

 The largest fruited specimens ever dis- 

 covered by me were in a little oasis, a 

 small volcanic cone of greater age than 

 the country surrounding it. This cone, 

 known as Hinakapanula, is located at 

 6,000 feet elevation in an absolute 

 desert lava field resembling very much 

 the famous "sand see" of Mr. Brown's 

 Java. There was no vegetation to be 

 found in this cinder plain, but the cone 

 was one mass of jungle — it having 

 escaped the destructive lava flows. 

 The plants were mainly Acacia koa 

 hatvaiiansis , Coprosma pubens, Styphe- 

 lia tameiameiae and Rubus macraei. 

 Here Rubus macraei was not an upright 

 shrub or bush but in reality a huge 

 liana some 20 feet in length with a^ 

 woody stem two inches in diameter. 

 The berries were of a dark rich purple 

 and at least two inches in diameter. A 

 remarkable feature of the plants was 

 the total absence of spines. 



In the fern forests near the volcano 

 of Kilauea there occurs another form 

 of Rubus macraei which is also spineless, 

 at least in older plants. This region 

 has been given over to cattle grazing 

 and consequently Rubus macraei has 

 disappeared as a terrestrial plant and 

 has only escaped total destruction there 

 by becoming epiphytic. All the plants 

 found there grow in the forks of moss- 

 covered trees, or fallen monarchs of 

 Acacia koa hawaiiensis. This would 

 indicate that if it does require an acid 

 soil it is at least not averse to such 

 conditions. To be sure the berries are 

 not as large as those found on Hualalai 

 or Mauna Kea Islands, but still are 

 over an inch and a half in diameter, and 



147 



