There is nothing I enjoy so much after Yom Kippur as going outdoors to build the Sukkah. If the Day of Atonement takes us to the depths and challenges of the inner world, Sukkot leads back out among the leaves and branches to an appreciation of the world of nature and agriculture around us.

Making a Sukkah, (a shelter with at least three walls, a roof of cut branches and leaves, and decorations from the year’s harvest) is the most tangible manifestation of simchah shel mitzvah, joy in the commandments. It’s fun to build and lovely to sit in; it’s a pleasure to share food there with guests.

Thinking about the festival begins early, with the seed catalogues in winter. What can we try to grow for our Succah? This year we have pumpkins, corn, even a small water melon (small really means tiny – it’s slightly larger than a tennis ball).

The Sukkah spans a paradox. It recalls our wanderings, our history of exile and flight, of being ‘of no fixed abode’. More than once refugees have asked me: ‘Can I give your address; I’m hoping for a letter’. Yet the Sukkah also embodies the privilege of having land to grow the fruits ‘of the vine and the fig tree’, wheat, barley and olives (and pumpkins and corn). Perhaps that’s the point: our blessings remind us of what not to take for granted.

The Sukkah also expresses another equally poignant tension. The Mishnah describes living for seven days in the Sukkah as going from our enduring home into a temporary shelter. The physical move probably amounts only to a few metres. But the emotional transition is far greater: from a safe and solid building to a fragile structure, subject to wind, rain and cold; from the assumption of security to the awareness of vulnerability, brevity and dependence.

This takes me to a frightening place. The earth with its fields, farms and forests signifies permanence. After the Flood, God promises that summer and winter, seed-time and harvest-time will never again cease. Generations come and go but ‘the earth remains forever’, says Ecclesiastes. But what if that’s no longer true? What if the very earth itself is vulnerable, perishable, together with all life on it? It’s a thought too unbearable to entertain, and too dangerous to fail to entertain.

The idea goes through my mind of building Not a Sukkah, the walls made entirely of waste plastic bottles collected off the street, the roof from the broken-up roots of decimated forests. To it I’ll invite not the traditional visitors, but a guest-list of extinct species. Instead of seven days of rejoicing, they’ll be turned, as God threatens in the Bible, into seven days of mourning for the loss of the sustaining beauty and fertility of this world.

I won’t do it. I don’t need it. That Sukkah is already under construction, – in innumerable throw away actions.

Instead, tomorrow I hope to join the first ever Peoples Walk for Wildlife, to which Everyone is invited – foresters, reserve wardens, teachers, students, children, scientists, artists, bloggers, activists, volunteers, gardeners. We are going to sing songs, play birdsong from the missing birds and share our love of all species. (Chris Packham).

Instead, my Sukkah will be a reminder to cherish the world, to waste and pollute less, and instead to know, love and respect more fully the natural world which is so wondrous and on which we and all life depend.