Planting It Forward

Forest in a Box

At our Treefest 2020 event we will be initiating the Tree by Tree “Forest in a Box” tree nursery project.

We will be planting more than 200 locally harvested Acorns using a method inspired by the copy nature forest floor seedling incubator system employed in The Woodland League “Forest in a Box” project. This system provides a growing environment that will optimise the health and vigour of saplings by recreating as much as possible the forest floor in which they would naturally be growing as part of natural regeneration.

The landowners hosting Treefest 2020 have committed to caring for the seedlings and after 2 years, the whips will be ready for planting out on the land, or at a future Treefest event.

This year we will pilot this practical solution for landowners willing to reforest areas of their land, to do so over the coming years, not just at a one-off event. And it is also a great opportunity to re-use tree guards! Each time we hold a tree planting event, we also pledge to plant more “Forests in boxes” – planting it forward.

What is a ‘Forest in a Box’ tree nursery?

Forest in a box is a mini tree nursery allowing people to grow from locally harvested seed a large number of seedling trees in a small space  (1m x 1m = 200 trees).

A development of the Dunemann bed system, the basic principle is to create ideal growing conditions for tree seeds, free from negative competition and predation, and so increase the chances of successful propagation.

The Dunemann system was developed by a German forester who noticed trees growing naturally on the natural forest floor were extremely healthy due to the conditions provided by nature in the natural forest. He then decided to experiment by copying this natural way to grow trees with great success. The intention is to optimise the health and vigour of the saplings by recreating as much as possible the forest floor in which they would naturally be growing as part of natural regeneration.

The loosely packed woodland soil medium allows for easy root penetration and most importantly promotes healthy relationships with mycorrhizal fungi. Additionally, the bare root whips are easy to lift from the soil, without damage, when ready for planting. Shade provided by the high sides of the box encourage the young trees to reach for the light, as well as offering protection from wind and cold in the saplings’ first 40cm of growth.

Forest in a box is ideal for growing common native UK tree species such as Oak, Ash, Beech, Sweet Chestnut, Hazel, etc. In 2 years  you should have up to 200 seedlings ready to plant out to grow on to become a woodland, or to be a resource for any other tree planting scheme.

Forest in a box mimics the woodland floor and soil system and, as such, is a valuable teaching resource. It demonstrates how soils work and encourages understanding of natural environmental systems in a practical and positive way. Growing seedlings promotes a sense of achievement and connection to nature.

Forest in a box consists of an open topped wooden box approximately 1m x 1m x 80cm tall. It has a cover/lid with rodent proof mesh.

Dunemann bed system with 1m high Hazels after 2 years. Image from The Woodland League

How is a ‘Forest in a Box’ made?

Inside, the box is loosely layered with growing medium consisting of;

  • First, a deep bed (about 40cm) of pure local woodland leaf mould. If leaf mould is unavailable a peat type compost mixed with very well rotted woodchip can be used.
  • Next a layer of fresh acorns (about ¾ of a bucket full) or other seeds.
  • Seeds are covered with another 10cm of leaf mould/compost
  • Add earthworms, mycorrhizal fungi (such as ‘Rootgrow’) and seaweed dust.
  • Finally, a 10cm layer of leaf litter. Water thoroughly and attach the cover to protect the seeds from rodents and birds.

The Woodland League Forest in a Box project

Maintenance is simple and consists of periodic weeding and watering as necessary..

After two years most of the acorns will have grown to be 40-60cm tall and can be planted directly into their final home or planted outside the box and grown on to be replanted when bigger.