The Council in Cambridge made a new cycle path that runs for miles around and into Cambridge, and they lined the path with saplings.
In parts, the saplings are planted three or four deep and close to one another. What you can see are the plastic sleeves that allow the saplings to grow without being browsed by Muntjac deer – which are the most likely browsers to eat them.
But why are the young trees planted so close to one another? It occurred to me that maybe the Council will thin them out when they have seen which do best and which can be sacrificed, but equally all the saplings could suffer from being planted so close in the first place.
If the intention is to thin them out, then what happens when the ‘duds’ are removed? Is that not going to disturb the root system of those being left?
This is what I wondered, and I asked for answers on Metafilter. If you haven’t seen. heard, or used the site, let me recommend it to you. I asked the question today about why these trees are planted so close to one another? Here are two of the replies I received.
This is how they do buffer restoration and protection plantings near streams, etc. where I live as well. Where we are they expect about a third of the plants will be lost in one way or another. If they expect that sort of loss where that planting is then maybe that’s appropriate spacing to start and the plants will sort of thin themselves. Also are they all tree saplings? That may be appropriate spacing for shrubs or smaller plants after the “self thinning.”
If plants die or don’t grow in the first year or two they may not actually remove the plants if they aren’t diseased. Presumably they’ll remove the sleeves.
Close planting is to encourage vertical growth as everyone struggles for the light. That means straighter trunks with fewer kinky side-branches. Also, as alluded above, because nobody knows at the beginning which whips will survive.
As for damage to the root-system of neighbours when the trees are thinned / die: the thinned saplings are cut close to the ground rather than uprooted, so the ground is undisturbed . . . and the vital underworld fungal network just diverts itself.