The Queen and the Prince of Wales have joined schoolchildren as they mark the start of the official planting session for The Queen's Green Canopy (QGC) at the Balmoral estate.
The monarch, 95, and her heir apparent, 72, took part in an outdoor forest school session with pupils and staff from Crathie Primary School at Balmoral's historic cricket pavilion.
During the mother-son outing, the Queen and Charles will "Plant a Tree for the Jubilee" to support the initiative, which will create a lasting legacy in tribute to Her Majesty's 70 years of service to the nation, through a network of trees planted in her name.
The monarch has been residing at her Scottish estate for her traditional summer break and the engagement marked the start of a busy autumn schedule for the Queen.
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WATCH: The Queen receives sweet card from schoolchildren in Balmoral
The planting of the copper beech tree coincided with schools, community groups, families and individuals starting their own tree planting projects across the country.
The QGC encourages tree planting to take place during October to March, to optimise the chance of trees surviving and flourishing.
As the Queen and Charles poured soil around the copper beech sapling, the Prince quipped: "Let's hope it will survive."
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Next year, the Queen will become the first British monarch to celebrate a Platinum Jubilee, having acceded to the throne on 6 February 1952, aged 25.
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At the end of the session, the Queen and the Prince of Wales joined the Crathie Primary School students for a group photograph with the newly planted tree. The photograph will be added to the QGC's interactive map, which will create a digital record of the green canopy of tree planting projects across the country.
The Queen sported a khaki green overcoat and an apt leaf-patterned scarf for the outing.
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The Queen looked thrilled as she was presented with a card from the schoolchildren.
The monarch thanked them for the "very kind" gesture after being presented with the card by Annie Hutchin, aged “six and a half”, and Skye Jones, nine.
Annie said afterwards: "She asked how we made it and said we did a lovely job."
Maia MacDougall, ten, said Charles asked what they had been learning and she told him about counting rings on trees to find out how old they were.
She added: "I’ve never been near the Queen before in person and it felt quite strange, because she's one of the most famous people in the world, but it was pretty cool.
"I never thought I would meet her."
Children from Crathie Primary School proudly show off the card they made for the Queen.
Crathie Primary School headteacher Lilian Field said: "Being out in the forest really helps the children's self-confidence, building initiative and for mental health and well-being as well, especially after lockdown.
"It was a lovely occasion for us. Giving a card is something we do every year after the Queen finishes her holiday at Balmoral, but this is the first time we've given her it in person.
"We made quite a special card this year. Every child made a picture of a tree and we put it together in a concertina-like way. We're just hoping the Queen has a big desk she can stretch it out on."
A stunning view of Balmoral Castle, where Her Majesty has been staying this summer.
The Queen has enjoyed visits from her family members, including the Duke and Duchess of Cambridge and their children as well as Princess Eugenie, Jack Brooksbank, and their baby son August.
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