[joyb]

I would think that their high polarity would make the oxygen atom very susceptible to hydrolysis. Why are they so unreactive? Steric hindrance?

[Babcock_Hall]

Draw out the mechanism and ask yourself what the leaving group would be.

[joyb]

So is it just that the leaving group would have to be an alkyl group?

[Altered State]

So is it just that the leaving group would have to be an alkyl group?

Isn't it good enough reason?

[Babcock_Hall]

So is it just that the leaving group would have to be an alkyl group?

I pictured diethyl ether in my mind, and I may be thinking of a different chemical process than you are.  If solvent attacked the carbon atom of the -CH₂- group, then ethoxide would be the leaving group.  This would not be a fast process.

[camptzak]

What pH (acid or base) do ethers hydrolyze at? I found a paper that might contain the answer but I do not have access!
http://pubs.acs.org/doi/abs/10.1021/ie0702882

[Altered State]

What pH (acid or base) do ethers hydrolyze at? I found a paper that might contain the answer but I do not have access!
http://pubs.acs.org/doi/abs/10.1021/ie0702882

Always Acid Media to break an ether C-O Bond, and it's always broken the less substituted Carbon bond.
What pH? It depends on the ether.
For example, dibuthyl ether would be way easier to hydrolyze than diphenylether (which one is extremelly difficult).

You also have to consider the exception of epoxides, that can be easily opened both in basic media (less substituted C) and acid media (most substituted).

[Babcock_Hall]

At room temperature, the reaction is specific-acid catalyzed, according to the paper.