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Branch with roots growing from section that was under gravel. © Eugene Brennan
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Plants
reproduce using multiple different methods. You probably know about
seeds, but other ways they can reproduce naturally include sending out
rhizomes (horizontal underground roots that send shoots to the surface)
and above or below ground stems called stolons (AKA runners in the case
of strawberries). Plants can be reproduced artificially by taking leaf
or stem cuttings, by division (splitting a plant down the middle into
two or more pieces using a spade or knife), budding (used for
propagating roses) and grafting (used for fruit trees and other plants
that don't readily grow from stem cuttings). Another method that occurs
naturally and can be done manually by gardeners is layering. This
involves laying a stem on the ground and covering it with soil or in the
case of aerial branches, surrounding the branch with some compost and
covering with a plastic bag or film. In both cases, roots eventually
grow from the branch at the point where it makes contact with the moist
soil or compost. Then the branch or stem can be cut off and planted and
will grow independently of its parent (although technically only seeds
have parents. Plants reproduced by other methods are clones ). The
photos below show layering that occurred naturally on a sycamore tree
down my garden. Whenever I'm doing construction I have to get rid of all
the soil. I've probably disposed of tens of tonnes of stuff over the
years, building up the ground or tipping it into the hedges. I had piled
up some clay around the sycamore tree and inadvertently buried one of
the still attached branches that was close to the ground. I had to cut
the branch to get a wheelbarrow under the tree this morning and when I
pulled the submerged section out of the soil, I discovered roots had
sprung from the side of it. I've also seen this happening around the
trunks of trees, when gravel was piled up against them.
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Roots growing from end of branch. © Eugene Brennan
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