Looks like bay laurel (Laurus nobilis). At first, I thought it was an olive.

I second Laurus nobilis, but I have a question -- is it hardy in Washington D.C.? -- I thought it was hardy only to Zone 8, and D.C. appears be be right on the border of 6b and 7a.

Do they take the plant in for the winter, cover it, is it a particularly hardy specimen with provenance from the extreme of its range, is it the "urban heat island effect" or is it just luck? Anyone know?

if they take that monster in.. i would like to see the conservatory they put it in.. lol ..

i was going to guess laurel ... but it was such a wild guess i felt ashamed ...

so is this the one i cook soup with ????

or the one i use to make my Olympic wreathes with ...

or both ...

ken

Laurus nobilis is what the sign said. When I got back home I found several leaves in my pocket (but how did they get there? :)
I understand that victorious athletes in ancient Greece wore a wreath of this plant and the tradition was started.
D.C. got zapped hard during Snowmegeddon and this plant came through unphased.
It is easily 20' tall and well-established. It also benefits from the "heat island effect".

another pop quiz from you ... lol ..

being from MD.. perhaps you dont know.. but snow is irrelevant to temp.. our worst storms come between 30 and 35 degrees ...

zone is more about min winter temps.. but snow has nothing to do with it directly ...

i surmise you know that.. but in case the lurkers need to know ... zone is mostly min winter temp .. not snow.. nor the ability to snow ..

is this the stuff in the fish flavoring stuff.. old bay???

ken

Here is a link that might be useful: so many bay questions.. so little time ... any why is laurel called bay ... one name not good enough????

Hardiness of Laurus nobilis increases with age - young plants are much more vulnerable to winter cold than are older, established ones. Should be hardy to at least 15F, possibly colder (local ones survived our single digit November freeze a couple of years ago).

In case you've never seen the flowers of Laurus nobilis here they are, pic taken today. Note how closely they are tucked into the axil.
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Besides the lowest temperature for hardiness, how long the cold temperatures last should be considered. By the way there is a Quercus Virginiana in Wash. DC, it is several decades old and doing fine. I believe it is near one of the Museums.

Sad to report that the noble Bay Laurel in the Nat'l Herb Garden fell victim to the record cold winter. I saw the tree today and it is dead as a door nail.
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Persea borbonia our native Red Bay is pictured here coming out of dormancy. It survived the winter like a champ. The ill fated Bay Laurel is in the background.
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Are you certain it's dead as a doornail?

I have a hedge of 20 15' tall Japanese privets, 14 of which have lost between 50% and 95% of their leaves (and most of those much closer to 95%). Our winter low was -2*. But they're sprouting new growth from the leafless branches.

And I have a couple of 5-year-old Mission figs (or Mission hybrids) which look pretty dead, but the folks on the Fig forum say in all likelihood they will come back from the roots ... though no fruit this year.

So the DC laurel's dead leaves might not be Nature's final verdict. (Of course the National Herb Garden may or may not go along with Nature's final verdict.)

I'm also hopeful that this tree is not necessarily completely dead. It may well sprout from the base. I've seen many a completely brown Bay revive. I hope the gardeners there give it a chance to recover before they condemn it.

Hope springs eternal in the human breast
As we can see, the tree has been cut and removed. The good news is that sprouts are coming back from the roots.
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Yes, Bay Laurel has the ability to resprout from the roots even if the entire top dies back. After the last Winter, one of mine made it; another never recuperated. But in a normal Zone 7 Winter, they do not defoliate.

Such a shame that that huge laurel tree died back. Oh well, hopefully the sprouts will harden by the winter.

The Red Bay in my yard took it hard. It defoliated and lost several branches. I got my Red Bay from seed from the one in the Herb Garden.

Has probably frozen off and come back multiple times. As for it being "large", "a monster", "noble" or "huge" one in Sacramento was 62 ft. tall in 1989. With the top end being considered the 70 ft. seen in Italy and Spain before 1995, various examples measured in Seattle during 2005 ranging up to 45 ft.