Rauhs Model

Rauh’s model represents the Cupressaceae family (cypress, juniper & redwood), some Araucariaceae, the Pinaceae family including most Pinus species, the Podocarpaceae family as well as angiosperms such as oak, maple and ash. It is a very common model for trees we encounter in bonsai.

The architecture according to Rauh’s model includes a monopodial trunk (one which continues to extend, and does not terminate) which grows rhythmically (on a seasonal cycle) and so develops tiers of branches, the branches themselves morphogenetically identical with the trunk (ie. they develop in the same way). Because the branches are identical, the trunk can be less dominant in this form and another stem can take over if the trunk is removed or damaged. Flowers and reproductive organs are always lateral and without effect on the growth of the shoot system.ref Often these are on short shoots.


An essential feature of Rauh’s model is that branches develop mainly by ‘prolepsis’, from dormant lateral buds close to the resting terminal bud.ref Prolepsis in this context means ‘the discontinuous development of a lateral from a terminal meristem to establish a branch, with some intervening period of rest of the lateral meristem’. So basically there is a gap or period of dormancy before the bud extends to form a branch. Whilst this might seem obvious to European readers, actually this mode of development is not what happens in other parts of the world, particularly the tropics, where continuous growth occurs, and this difference creates differences in the tree architectures visible in those different places.

It was noted in one study that Apple trees follow Rauh’s model during their juvenile phase but a different one during their reproductive phase (ie. their flowers terminate shoots and affect the branching after this point).ref