The answer, I think, is that it was intended to fertilize an eating apple tree that used to be on the plot.
I've been in two minds whether to keep it or not. It's an attractive little tree and the local wildlife enjoy it, but I can't eat the fruit.
Before I condemned the tree I decided to have a go at making apple jelly. Lots of cooks think it's best made with crabs and they do contain lots of natural pectin, the stuff that makes jelly or jam set.
It's then put in a large pan (I did it in two batches) with 300ml (1 pint) of water for each 450g (1lb) of fruit and brought to a gentle simmer. The fruit needs to cook for 20-30 minutes and is squashed with a wooden spoon or potato masher to release the juice.
The pulp is then put into a jelly bag strainer and left to drip for several hours (I left mine overnight).
Apples can have a second cooking to release more juice, adding half as much water 150ml (1/2 pint) per 450g (1lb). The pulp is strained again and the juice added to the first batch. I got about 3 l (5 pints) of juice.
To make the jelly you need 450g (1lb) of sugar for every 300ml (1 pint) of juice. First put the juice in a pan (not more than half full) over a gentle heat. When the juice is quite hot add the sugar and stir until it's all dissolved. Then turn up the heat and boil rapidly (called a rolling boil).
The hot jelly is then poured into sterilized jars and topped with wax paper discs and lids.
I ended up with 10 jars of beautiful pink jelly, and it tastes delicious. I like it spread on toast and have also used some in a sauce for pork chops.