[pbs] Scadoxus multiflorus seed
John Grimshaw
j.grimshaw at virgin.net
Thu Sep 7 03:20:05 EDT 2006
Jim McKenney wrote:
The bright orange fruits are ornamental;
> has anyone ever seen a plant of any of the Scadoxus species where most of
> the flowers have set fruit? That must be a spectacular sight!
I have and they are.
What is puzzling to me is the question of seed dispersal in amaryllids with
a fleshy berry and rather soft-skinned seed. Scadoxus, Haemanthus, Clivia
have such fruits, turning from green to red when ripe, a characteristic of
bird-dispersed fruits. The berries are also within the gape size of most of
the 'usual suspects' of fruit-eating birds in Africa. But can the seeds
withstand the action of the crop before either regurgitation or defecation?
The distribution of Scadoxus multiflorus and S. puniceus over huge tracts of
Africa demonstrate that dispersal is effective and potentially
long-distance. The range of Clivia is probably restrained by the
availability of suitable habitat. Does anyone know if there are studies on
dispersal in wild Clivia?
Even more intriguing is the case of certain Crinum, especially the East
African plains species C. kirkii, which develops a large red capsule
containing the usual lumpy, greenish seeds. When ripe this object is very
conspicuous and would be expected to be an attractant to dispersers. But a
soft crinum seed would not last long in the gizzard of an ostrich or ground
hornbill, which are obvious potential candidates. Perhaps the red coloration
is unimportant in this case and the seeds just roll away in the usual Crinum
way as the capsule opens. I do not know how big Crinum seeds in dry places
move more than a few feet from their parent, but can conceive that a rodent
or primate might pick them up and carry them a short way (those in damp
habitats, including coastlines, obviously have flotation options).
John Grimshaw
Dr John M. Grimshaw
Garden Manager, Colesbourne Gardens
Sycamore Cottage
Colesbourne
Nr Cheltenham
Gloucestershire GL53 9NP
Website: www.colesbournegardens.org.uk
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