Something you can easily find in the middle of the city. Chestnut on the left, oak on the right. The chestnut is the variety with yellowish-green blossoms. Perhaps the one with white or pink (haven’t seen the pink ones here) would give a different shade? The oak is a young tree, also just bloomed recently (if those are considered blooms), according to my dad the variety is the Northern red oak (Quercus rubra or Quercus borealis). The lighter shade is after less than an hour in a dye, the darker one – overnight. No issue with chestnut whatsoever, the darker shade of oak was powdery and was coming off, but it’s possible that would be rectified with repeated dyeing rather that the whole night straight, or also overdyeing with another dye for final color.
The recipe is very simple, took a bunch of young green leaves (use as many as possible, a good bunch), soaked in water overnight, cooked for about 20 min., when cool strained the leaves, added alum and started using. Didn’t prep the eggs in any way at all, didn’t even wipe them with vinegar as I sometimes do. Excellent results, highly recommended.
I also tried a maple with reddish brown leaves, and it did give green but very uneven, it might take some more playing with.