Translation:There is a spruce and six squirrels over here.
Okay, I’ve surveyed a section of my UK and Commonwealth ‘compatriots’ (13 of them: 10 Brits, 1 Australian, 1 Canadian and 1 New Zealander), asking them which of the following they would NATURALLY say:
a) "There is a spruce and six squirrels over here"
b) "There are a spruce and six squirrels over here"
Only 2 picked B without any advisories; both Brits. 11 plumped for A, but 3 of these said while they acknowledged B was “technically correct” in grammar terms, they would always say A as B sounded awkward. One of these 3 who hedged their bets commented that the A form with “There’s” rather than “There is” was probably the most natural-sounding option of all (I concur).
I've noticed that in the US they're quite 'strict' with collective nouns always being followed by a singular verb, so an American would usually say:
"The class is studying hard."
while a Brit can merrily pick from both the singular and plural forms as they see fit, as in:
"The class is studying hard." OR "The class are studying hard." (I'd pretty much always pick the latter).
But I'd not (knowingly) come across splitting the singular and plural like this before when two things are involved. I know it's logically counterintuitive to say "is" when more than one thing is being discussed, but Brits - and their Commonwealth buddies - seem to naturally prioritise the first thing mentioned before the "and"; treating them separately.
Hey - we invented (okay, mainly assimilated!) the language, so I suppose we can do what we like! :)
In answer to your query if the sentence had been reversed, then, yes, the plural would certainly have been used, so it seems the order is key:
"There are six squirrels and a spruce over here."
Actually, for the record, Americans are just as likely to use the singular verb in this case. It's called "attraction." I hear this sort of inconsistency all the time. My point is only that to write the sentence correctly you would follow the rule and use a plural verb regardless of word order. Would you write in a report, "In the car there was a man. a woman, and two children" or "Here in the forest is an oak tree and several maples"?
On the other hand, when the conjunction is "or," the verb agrees with the nearest noun: "As long as you or I am here, we can proceed."
As for collective nouns like parliament and class, it is true that Americans are more likely to use a singular verb, but either works, depending partly on context and partly on stylistic preference: "The committee is meeting at this moment," vs. perhaps, "The committee are far from unanimous on this issue."