Queen Elizabeth was captured giving a rare quip while filming The Queen’s Green Planet, a documentary airing on ITV in the U.K. on April 16.
The documentary highlights an ambitious environmental project, The Queen’s Canopy, to safeguard forests around the world via the 53 countries of the Commonwealth.
At the center of the film is a charming conversation with fellow 91-year-old Sir David Attenborough about the Queen’s love of trees and her hope for the future.
At one point, the Queen and Attenborough were interrupted by the whirring of helicopters above, which led the Queen to make a joke about what the sound reminded her of.
“Sounds like President Trump,” she deadpanned. “Or President Obama.”
She also talked about planting trees in her back garden for each of her four children — Charles, Anne, Andrew and Edward — and reveals there are 1,400 trees in the palace grounds.
When they spot a bent sapling, Attenborough says they’ll ignore it as it “doesn’t seem to be doing very well.”
The Queen quips, “Are you sure that’s meant to be like that? Somebody sat on it I think at a garden party.”
The conversation with Attenborough, who made his name touring the globe making groundbreaking programs about the natural world and the threats to it, meanders from bees to roses and the noise of helicopters overhead in busy London. (Is that President Trump or President Obama? the Queen ponders.)
As they discuss horse chestnut trees during their stroll, the Queen remarks at how restrictions have prevented children from playing a favorite game, conkers. “Wasn’t it recently that somebody tried to stop children playing conkers?”
When Attenborough suggests this is because of “health and safety,” she agrees and laughs, adding, “Well, it seems to me quite harmless sort of battle thing, isn’t it?”
The Queen also talked about her family’s Christmas tree traditions, particularly when it comes to ornaments.
“This is always the problem . . . The children love knocking those off,” she said. “Well, my great-grandchildren do. And the great thing is to make them decorate it . . . And they’re a bit more careful.”
This article originally appeared on PEOPLE