🌰You know and I know that there are two sorts of chestnuts in these islands. Horse chestnuts = conkers Aesculus hippocastanum vs sweet chestnuts Castanea sativa. Don't be eating horse chestnut: it is loaded with aesculin a coumarin related toxin, not to mention getting all frothed up inside by the soapy saponins which are also present at high titre. They are both called chestnuts because a) nuts b) 'similar' palmate multilobed leaves. But the two species are about as far as they could be phylogenetically. A horse chestnut freshly blurfed from its shell is a gorgeous thing.
🌰I've always been disappointed by fresh-fallen sweet chestnuts, though. The covering is much more offensively spiny - you have to be a bit previous in your attack to get ahead of squirrels - and the insides are, for me, always wizened husks or too small to bother with. Which is a bummer because I love marrons glacés or chestnuts roasting on an open fire or in any other form.
🌰In 2007 we planted a few hundred 10 y.o. oak and other trees courtesy of our pal Rene. In among that micro-forest were about a dozen Castanea sativa. Some of which were thinned by Sean the Forester in 2022. In Sept 2025, I was stravaiging through our wood when I found a tuthree sweet chestnuts on the ground. Inside was the usual disappointment. A month later under a different tree the leave litter was dense with fallen chestnuts in various states of undress. I shucked a bunch right there and then went back for a bucket to do my shucking in the warm and dry [R with old boot for scale]. I went back a couple of times and stopped when I had ~10lb = 4.5kg. Leaving some for wild loafers. I was amazed and delirah, especially after I cut a couple of small ones in half and chugged down the contents.🌰According the Dau.II & the Internets, chestnuts will keep for a year if frozen or a month in the fridge. But this is not great advice. Chestnuts sweat through their shells and a bagful gets soggy in the fridge. And turn quickly furry if left out of the fridge. I triaged my horde and put 2x 500g of the biggest shiniest nuts in the freezer against Christmas stuffing. I also passed a 1° quality bag to La Torbellina my cookie neighbour. She scored the shells with a cross and boiled them with aniseed and lemon in the eSpanish way. Scoring and roasting is only sensible to process small amounts (for immediate consumption) because as the nuts cool, the inner membrane re-glues itself to the nut.
🌰The last two bags, of 2° grade and smaller nuts, having lurked in the fridge for a week, were triaged, cut in half and boiled for 5 minutes. Six nuts had decided to make an attempt at sprouting-for-posterity, so I potted them out in sieved compost [before boiling!]. About 10% of the remainder were squidgy or discoloured within. Compost! Processing the hot nuts gives you the same sort of wet burns as Seville oranges when making marmalade. I found that the best shucking tool was two opposing thumbs: in ideal cases that popped the half nut out of shell and membrane. In other cases it was more of a struggle. I hope my thumb nails don't get infected from compacted matter; they were quite sore when I'd finished. The work-to-reward ratio is not as positive as for marmalade, but 8oz = 225g has been frozen against Christmas [see L], as well as the larger unshucked qnty already there.🌰The smaller chestnuts looked suspiciously like filberts / hazel Corylus avellana, but these two species are in different families (as below). Castanea is sibling to beech Fagus sylvatica and oak Quercus robur in Family Fagaceae although their fruit look quite different. Which is a lesson in taxonomy: don't over-emphasize Obvs features, like palmate leaves, to determine evolutionary relationships.
| English | Genus | Family |
| Alder | Alnus | Betulaceae |
| Birch | Betula | Betulaceae |
| Hornbeam | Carpinus | Betulaceae |
| Hazel | Corylus | Betulaceae |
| Chestnut | Castanea | Fagaceae |
| Beech | Fagus | Fagaceae |
| Oak | Quercus | Fagaceae |
| Hickory | Carya | Juglandaceae |
| Pecan | Carya | Juglandaceae |
| Walnut | Juglans | Juglandaceae |










