Deadly... or not?

Ann Parker here, kicking off my shoes for a TGIF post. I've run into a bit of a sticky wicket this week in trying to negotiate the past from a present frame of reference. (I love the term "sticky wicket," btw. Comes from cricket, first used in 1882, so I can't use it in my fiction, more's the pity.)

This week, I've been obsessing over certain kinds of plants (i.e., poisonous), their effects on people and livestock, and their names, both common and scientific. I've been running into sticky wickets and time-travel whiplash, left and right.

What to do if an "old" reference says a plant is highly poisonous, and recent sources say it's not?

What to do if the common names of the plant changed over time, but I'm not sure when/where a certain name came into existence?

For instance, if a character from 1880 is talking about this plant:

 

 Would they call it:

• Golden Smoke?
• Scrambled Eggs?

And if it flourishes in a particular area NOW, was it there THEN?

So far, I've been going to Google Books, putting the plant name in the search engine, limiting the search to items before 1880, and seeing what pops up.

A long process, and I'm still thrashing about.

And I don't even want to go into the thicket of scientific names, that seem to morph over time.

So, it's back to thickets and wickets until next week. Same time, same channel.