<what is yarok> Rashi on Hullin 47b (colors of the lung) ‘green but not like grass, …..rather like kashos (hops?)… carcom (saffron or turmeric), like egg…(from pale yellow to blue)
The conclusion of the gemara there is that yarok for lung is k’karti. If this is the leek, leek leaves are dark blue-green at the top. This is relevant the the requirement of misheyakir- between techels and karti a close match.
As for the matching of the vegetative matter of the Mishna to that of today, if you don’t hold by Dr. Felix, there is the Chazon Ish in the Igros that states that the kezayit and barley weight shiurim were given as plant products that would be everywhere in every time, regardless of the changes of size due to passage of time change of place or climate