Cabbie Blog has a nice piece about war work involving the use of conkers (horse chestnuts) to create ammunition during the First World War.

Conkers is a game played by two, each with a conker threaded onto a piece of string knotted below it. You take turns striking each other’s conker until one of them breaks. The break may come when you receive a hit or when you strike your opponent’s. Disaster may result from tangled strings. Most frustrating. Various techniques of hardening your conkers were attempted: the only one I remember trying is baking them in the oven, which never seemed to do any good. But do not allow yourselves to be beguiled into the image of wartime conker battles.

Since 1889 the British Army had been using cordite to replace gunpowder in the manufacture of bullets and shells. An essential ingredient of cordite is acetone which was in short supply. In 1916 Chaim Weizmann, then a lecturer in chemistry at Manchester University, developed a method using bacteria to ferment starch, a process which yields a mixture of 3 parts acetone, 6 parts butanol and 1 part ethanol. After the War the largest plant in the world, in Peoria IL, would use molasses as raw material, but in the early years of the War, wood was the raw material you turned to for Professor Weizmann’s bug, Colostridium acetobutylicum, to chew on, other starches no doubt being needed for food! Unfortunately it was soon recognized that there were not enough trees in the whole of Great Britain to yield sufficient acetone to make enough bullets to win the war, and alternatives were sought.

Cabbie Blog tells us that school children were paid to gather conkers — something we’d all do anyway for free — though we would of course keep them for conker fights. I do recall as a schoolchild being paid to collect rosehips as part of the WWII effort to keep the population healthy, and we were given a day’s holiday every year to harvest potatoes. I suppose I would have sold conkers had there been a market, certainly my backup supply. Harvesting conkers involves the use of a big stick which you hurl up into the tree, knocking the ripe chestnuts down. You then rush to grub in the grass to get as many of them as you can grab, chucking the green shells away. It does however seem hard to imagine that there could ever have been enough chestnuts to make a difference to the war effort.

We had a great chestnut tree in our garden, and I’d try to restrict access to it as well as I could. Today I overlook a big chestnut tree in the next-door apartment complex, but for the last few years it has been showing signs of distress. The leaves have been turning brown far too early; they started browning in late July this year and the nuts are not developing remaining wizened little black balls. In the Spring we had a good show of blossoms, but most have not developed into fruit. 2017 was a problem year for this tree too, though it did better in 2018 and 2019. Is heat the problem? We seem to be evolving into a sub-tropical climate here in Manhattan. I don’t think the tree can be 100 years old yet: o tree thou art sick. Maybe the invisible worm has got it.