Bale cutter
Bale cutters are machines that are used in tree nurseries and horticultural businesses to cut the root balls of trees or bushes from the earth and then to lift the trees out of the earth. They are available as an attachment for a tractor or as a self-propelled device.
The devices are used to move trees for further cultivation in the tree nursery (to "school") or to harvest them for sale as bale goods. In contrast to so-called "bare-root goods", trees are called bale goods, where the soil adhering to the roots largely remains. So that the bale of roots and soil does not disintegrate, it is balled up, i.e. tied into a cloth, net, wire mesh or a combination of these or, alternatively, placed in plant container pots. The jute and non-galvanized wire mesh mostly used for this purpose are usually not removed during planting and rot or corrode after a few years, so that roots that have grown through are not constricted as they grow thick. The size of the ball is based on the size of the wood and is usually eight times the trunk diameter. The bale cutters can be equipped with cutting tools of different sizes.
The multiple schooling of a wood in the nursery is done, among other things, to keep the root ball compact. It is necessary to be able to transplant larger trees at all or at an economical cost and in a leafy state. If you simply let a tree grow, the roots become too large and far-reaching. If you dig such a tree compactly, then roots would have to be cut off or chopped off. The tree loses too many (fine) roots and after replanting the (leafy or non-leafy) crown cannot be supplied with enough water and nutrients. Trees with bare roots (mostly with fewer fine roots) are only sold and used without leaves, i.e. in early spring and autumn. Balled goods and plants in plant containers, on the other hand, can be planted at any time during the frost-free period, which means that the work involved in plant production, sale of plants and garden design is better distributed over the year and thus enables more economic yield and permanent jobs (instead of day labor and seasonal work ) than when everything can only be done during peak season.
Transplanting trees with balls of trees keeps the roots compact, but is very expensive because of the time required to do it by hand, so the price increases with the size of the tree and the number of years it has been standing. In principle, the wood is only lifted together with the balls and either rotated slightly (so that the root cut surfaces do not grow together again) or reinserted in the grave hole that was created next to it. Bale cutters have streamlined these transplanting and excavation processes considerably, so that even larger trees can be kept economically transplantable and can also be transplanted with leaves. At the same time, even today with the use of machines, repeated schooling with ever larger root balls makes the price of larger trees very expensive.
literature
- Ulrich Sachweh (editor): The gardener, volume 3, tree nursery, fruit growing, seed growing, vegetable growing . 2nd edition, Ulmer, Stuttgart 1986/1989, ISBN 3-8001-1148-9 , pp. 45 ff., 66, 156 f.