Walking through our botanical garden, you may notice that some plants disperse their seeds far beyond their immediate habitat. So, the black elderberry (Sambucus nigra L.) is found almost throughout the garden, although it was originally planted in the Europe, Crimea and the Caucasus section. The paper mulberry (Broussonetia papyrifera (L.) Vent.) has also spread outside the East Asia section. Look, you can see them growing to the left of the path leading to the centre of the garden. That is, unless the botanical garden staff responsible for monitoring such "unauthorized settlement" have already removed them. There are dozens of examples of this. How does it happen?
The first reason is self-seeding, when plant seeds spread naturally across an area. The wind carries flying fruits, and the seeds germinate in new places. Self-seeding is also called anemochory from the Greek words meaning "wind" and "spreading".
The second way of the seed dispersal is with the help of birds. The specialist term for this is ornithochory from the Greek words meaning "bird" and "spreading". Birds love the ripe fruits of black elderberry and paper mulberry. Passing through the digestive tract, the seeds do not lose their ability to germinate, which they do after birds defecate. Ornithochory also includes dissemination via seeds sticking to birds' paws, feathers, and beak.
