These works focus on problems in forestry associated, among others, with workforce shortages, low effectiveness, and a lack of automated solutions for forest planting. In one minute, the device can plant up to 7 saplings of forest trees, with their root system covered. The project was implemented using the research and development funds of the State Forests, by researchers and engineers from the University of Agriculture in Krakow, the Łukasiewicz – Poznań Institute of Technology, the AGH University of Science and Technology, and the Forest Technology Centre in Jarocin.

Currently, the forestry sector in the European Union does not have automated planting machines that could be used to quickly reclaim post-logging areas. These works are usually performed manually, and sometimes by tractor planters. In both cases, the post-logging area needs to be appropriately prepared earlier, e.g., by ploughing it with a forestry plough, and this is associated with additional significant energy expenditures. Semi-automated planting heads installed on booms of construction machines, e.g., heavy-duty excavators, are known and used, mainly in the Scandinavian countries[1]. The prototype of a mobile automaton can plant saplings of forest trees with their root system covered, on cleared post-logging sites, without a need for their energy-consuming preparation by, e.g., ploughing. Such saplings are produced at container nurseries in special containers.

Great support for foresters 

Implementation of modern and automated technological systems enables elimination of manual work. Afforestation techniques and technologies that are currently used are labour- and cost-consuming. The forest policy of the European Union Member States establishes as its objective an increase in mixed-species tree stands and restoration of forest lands after logging and hauling operations. Increasingly often, brownfield and agricultural areas that for various reasons will not be further used for agricultural purposes, are also designated for afforestation.

Forest tree saplings with a covered root system, produced in container nurseries in controlled conditions, are usually planted manually, using a planter. However, manual planting of so many saplings in the ground requires a significant expenditure of labour.

‘Manual works in forest management, including planting, are very onerous, and energy expenditure of working people is very high. It is a very monotonous work. Due to monotony and a significant static load during work, it is increasingly difficult to find workers for this work. Also, tiredness is a cause of planned and hidden breaks at work. Replacing human work with an automated machine will increase the afforestation productivity and improve the quality of these operations,’ explains professor Paweł Tylek from the University of Agriculture in Krakow, the head of this project.

The researchers also emphasise that the work of the robot will allow to reduce losses in saplings during forest planting. This results from the fact that planting of saplings grown in standard cassettes reduces the transplant shock caused by their handling, e.g., by taking saplings from cassettes several times, which frequently leads to drying and soil crumbling in the root system.

‘In the case of manual and mechanical planting, frequently the sapling is not planted vertically, and this needs to be adjusted manually in already planted rows, leading to further labour and costs,’ adds professor Tylek.

How does the robot operate?

A mobile automaton, called RoboFoR by its creators, contains several units working together, including a self-levelling drive system, a system for storage and feeding saplings consisting of a rotating feeding table, a unit for collecting and a feeding saplings, a buffer unit, and a planting unit comprising of a roller forming sites, an opening planter and a subunit pressing saplings down. Everything is automatically monitored and controlled by remote control systems, with a satellite navigation unit supporting selection of a planting site. The device works in a continuous way. It moves around an initially cleared post-logging site, on which the forest is to be renewed. The robot plants saplings appropriately spaced, and after the planter places them in the ground, the soil around the sampling and the root system is compacted with special wheels. This procedure removes air pockets and allows the root system to connect with the soil, so in consequence water can move up towards the roots. The automaton is adapted to operate two standard types of plastic nursery cassettes, so both deciduous trees and conifers can be planted, which are usually planted in two different types of cassettes.

The technological process of a prototype of the mobile automaton for planting saplings of forest trees with a covered root system is conducted automatically and consists of several activities.

‘A roller prepares the site by removing the top layer of the soil with plants growing in it, and clears small post-logging residues. Then the planter is lowered into thus prepared site, forms a hole and inserts a sapling inside, and rolling wheels press it down into the soil. The sapling is placed in the planter after it is collected by a gripper from a nursery cassette in a nest on the rotating table. The sapling collected by the gripper is fed into a channel of the buffer unit, from which it is released into the planter channel at an appropriate moment,’ explains Florian Adamczyk, PhD (Eng.), an expert from the Centre of Agricultural and Food Technology, at the Łukasiewicz – Poznań Institute of Technology.

The device plants saplings according to the established density resulting from the currently applicable forest cultivation principles. The mobile automaton contains technical solutions and IT applications previously used in very distant areas of information technologies and forestry. The high level of its innovativeness is confirmed by the fact that during research and development works, applications for seven inventions were submitted to the RP Patent Office. Among them, only one design referred to proprietary equipment for monitoring and measurements used to determine physical characteristics of saplings grown in container nurseries, and the remaining six concerned innovative technological solutions applied in the RoboFoR automaton.

The project under which RoboFoR was developed lasted three years and ended in autumn of 2022. A concept for this project resulted from the previous cooperation between the University of Agriculture in Krakow, the AGH University of Science and Technology, and the Centre of Agricultural and Food Technology at the Łukasiewicz – Poznań Institute of Technology.

‘These entities were consortium members formed for joint projects implemented under the NCBR Applied Research Programme. Very good mutual relations, correct cooperation during performance of those projects, and knowledge of current problems faced by the forestry formed a basis for drawing up together a project application submitted to the General Directorate of the State Forests in the middle of 2018,’ say Julia Gościańska-Łowińska, PhD, the director of the Centre of Agricultural and Food Technology at the Łukasiewicz – Poznań Institute of Technology.

The target group for the new product consist mainly of managers of state and private forests, companies performing revitalisation of brownfield sites and of post-agricultural and reclaimed lands, associations of forestry enterprises and forestry services companies, and producers of forest reproductive material.