Choosing your seedlings

Forest seedlings are woody plants grown from seed material, parts of seedlings, or self-seedlings, used for afforestation. Traditionally, forest seedlings grown in nurseries are further divided into two categories.

The first category comprises 1-2 year old planting material grown from seed and not replanted. They may come in containers or rolls.

The second category includes seedlings up to about 5 years old, grown from seed, which are dug and replanted when they are 1-2 years old and then grown for another 1-3 years. Traditionally, the name of such seedlings is accompanied by a “formula” for their production, e.g., spruce 2+2, which means that we have a 4-year-old seedling sown to grow for 2 years, then dug up, transplanted, and then grown again for 2 years. Replanting is beneficial as it produces a lot more fine roots, because the replanted seedlings are less dense than sown ones, and it allows space for the sprout to develop.

What do IP forest managers plant this season?

Birch comes in 1k, which is a standard container. This birch is sown in 2nd rotation, i.e., the last week of May to the first week of June. It is sown in F50 pots and grown in these pots until germination in greenhouses. After germination, they are transported on pallets to the field, where they are irrigated and continue to grow until their autumn sale. If not sold in the autumn, they are then bagged, transported to freezers, and frozen until spring planting.

Birch can also come in 0.5k+1, i.e., birch with an improved root system. We have used them the most. They are sown in the 1st rotation, i.e., in April, in F50 pots, kept in a greenhouse with regulated temperature and watering. In June, the seedlings are potted outside and transported to the field for planting in open beds. Watering and fertilization are continued until autumn. In autumn, they are used for forest planting or left in the beds until spring. In spring, seedlings are dug up by the end of March and placed in fridges at +1°C to await the foresters who will take them to the logging sites. This type of planting material is not kept in freezers over the winter. Usually, they are seedlings of a larger height and are 10 cents more expensive than 1k seedlings.

We only use 1k+1 or 1k+2 spruce seedlings with an improved root system. As a general rule, spruce is sown in the 1st rotation, i.e., in April. It is grown as containerized spruce until July. In July, it is transported to the field for planting into open ground beds. If grown in open ground until the following spring, it is considered 1k+1, if grown in open ground for 2 years then 1k+2. During all this time, the plants are watered, fertilized, weeded, and the roots are cut every few years to form a tufted root system.

We also used two types of pine seedlings this season:

One-year-old seedlings grown in a greenhouse and sown in the 2nd rotation at the end of May in open ground beds. On their sides, the greenhouses are open for natural ventilation purposes. Seedlings are watered, fertilized, and weeded. After about 4 months, by about October, they have reached the minimum standard of about 10 cm. They are usually left until spring and taken out just before being transported to the forest. Outdoor pine grown outside the greenhouse usually do not reach the minimum height after 1 year, which is why nurseries avoid selling 1-year-old outdoor seedlings.

Two-year-old seedlings grown outdoors. They are sown similarly to one-year-old seedlings but left to grow for another year. The roots are cut every year to form lateral roots next to the anchor root. No two-year-old seedlings are grown in greenhouses.