Product: Birch leaves minced - Bulk
Characteristic
Look and color: Green
Flavor: Bitter herbal
Nutrition 100 g: kJ 66 / Kcal 16,
total fat 0,2 g of which saturated fat 0 g,
Carbohydrate 3 g, of which sugar 1,8 g,
protein 7 g
0.2*9 + 7*4 + 3*4 = 41.8kcal
Not going to make you fat but not too shabby either, especially the protein content. Seems you run into protein toxicity issues pretty fast around 1000kcal, but if you enter ketosis it might be a good way to protein so your muscles don't waste.
However. This book from 1963 seems familiar "Guerilla Warfare, conditions and outlines". Maybe there is some cooking recipes, too: https://www.doria.fi/bitstream/handle/10024/130579/Sotataido...
Puolustusvoimat, Luonnonmuonaohje (LUMO) 1985
https://puolustusvoimat.fi/documents/1948673/2258487/PEVIEST...
Tuon mukaan koivunlehtiä pitää syödä 1.1 kiloa elinvoimat ylläpitävan (5 MJ) energian saamiseksi, eli olisi hieman parempi kuin pettu. Ei hullumpi (108 kcal/100g) Noin suurta määrää ei suositella.