Larch Larix spp

The water-extractable arabinogalactans are most abundant in the larches (Larix spp.). The most extensively studied has been that of the heartwood of the western larch Larix occidentalis). The source, production, properties, and potential uses of this polysaccharide are reviewed in Chap. 10.2.2. 

McAfee, B.J., E.E. White, L.E. Pelcher and M.S. Lapp. 1993. Root induction in pine (Pinus) and larch (Larix) spp. using Agrobacterium rhizogenes. Plant Cell, Tissue Organ Cult. 34 53-62. 

C12H22O11 342.299 Structural unit in the glucomannans of plant hemicelluloses. Isol. from the partial acid hydrolysates of the glucomannans from Amorphophallus spp., white spruce (Pinus glauca), western hemlock (Tsuga heterophylla), red maple (Acer rubrum), eastern white pine (Pinus strobus), larch (Larix decidua), jack pine (Pinus bank-siana) and from Narcissus tazetta from hemicelluloses of lobolly pine (Pinus taeda) and in trace amounts from the acetolysates of the a-celluloses from white birch (Betula papyrifera) and slash pine... 

D-Galactose has been found in Siberian larch Larix sibirica) wood (28), the spring sap of birches Betula spp.) (103, 149), the xylem of Scots pine Pinus sylvestris) (27), and red beech Fagus sylvatica) sap (150). D-Mannose has been found in saps (149, 150). Both may be more widespread than indicated. 

Arabinogalactan occurs in high concentration (5% to 35%, dry weight basis) in the heartwood of many species of Larix, a deciduous conifer native to the temperate and subarctic zones of the Northern Hemisphere in fact, the presence of this water-soluble, easily extractable polysaccharide is characteristic of Larix spp. Larch arabinogalactan will accumulate in masses under the bark as a result of injuries however, this supply is limited and its collection is difficult. 

---