**Preface to "Fast-Growing Trees Species—Opportunities and Risks for Sustainable Agricultural and Forest Land Use Systems"**

Cultivation systems with fast-growing tree species are often discussed, with much debate, in both science and practice. They are very diverse and pose opportunities as well as risks for land users and the surrounding ecosystems. Many different tree species and their varieties can be established on sites (usually) used for forestry; they can also be grown in short-rotation plantations (SRC) or in agroforestry systems (AFS) on agricultural soils. In most cases, the goals of the land users determine the choice of tree species and cultivation system, the rotation times, and their management. Thus, there is not only a large variety of management variants and technical and technological innovations, but also a large number of interactions with the surrounding ecosystems. In addition to the considerable effects on biodiversity in different landscapes, the tree–soil interactions also play an important role. For this reason, this Special Issue intends to present new findings from science and practice in this broad field of fast-growing tree species cultivation in all its forms.

> **Dirk Landgraf** *Editor*

### *Editorial* **Fast-Growing Trees Species—Opportunities and Risks for Sustainable Agricultural and Forest Land Use Systems**

**Dirk Landgraf**

Faculty of Landscape Architecture, Horticulture and Forestry, University of Applied Sciences Erfurt, Leipziger Strasse 77, 99085 Erfurt, Germany; dirk.landgraf@fh-erfurt.de

The cultivation of fast-growing tree species has noticeably increased worldwide in recent years. Fast-growing tree species are cultivated in different land use systems. In addition to being classically cultivated in forests, they are also cultivated in short-rotation coppices (SRC) with different rotation intervals on forest and agricultural land. Moreover, in recent years, people have become increasingly aware of cultivation in agroforestry systems.

Due to these intensive practical activities, many new questions concerning the management of fast-growing tree species are waiting to be answered using applied and basic research. Thus, a large number of publications by researchers worldwide can currently be found in a wide variety of journals.

In addition to numerous articles, Special Issues on fast-growing tree species have also published by several journals. I would particularly like to highlight the Special Issue in the *BioEnergy Research* journal on the subject of "Sustainable Biomass Value Chains Based on Poplar Plantations in European Rural Areas" [1] and the Special Issue that followed shortly thereafter in the *Forests* journal, entitled "Growth and Development of Short Rotation Woody Crops for Rural and Urban Applications" [2].

While these two Special Issues specifically focused on short-rotation woody crops, the focus of the current Special Issue is much broader. It contains a total of ten papers, which mainly come from Germany (7), but also from Poland (1), the Czech Republic (1) and China (1). It also needs to be emphasized that the authors of these articles often represent an international team.

The articles in this Special Issue cover a very wide range of topics. In addition to research on breeding [3] and on the influence of pruning practices on the height growth of paulownia [4], three articles deal with the influence of site characteristics and nutrient availability on the physiology and yield security of fast-growing tree species [5–7]. The article by Kalita et al. focuses on the modeling of soil carbon in *Salix* plantations [8], while the article by Boruszewski et al. reports on potentially suitable areas for the planting of fast-growing tree species in Poland [9]. Zitzmann and Rode [10] examine the impact of short-rotation plantation management on phytodiversity [10], while Helbig et al. deal with the influence of leaf feeding on the growth of poplars and willows [11]. Finally, Hernandez-Estrada et al. describe the dry matter loss of poplar wood chips during storage [12].

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The author declares no conflict of interest.

**Citation:** Landgraf, D. Fast-Growing Trees Species—Opportunities and Risks for Sustainable Agricultural and Forest Land Use Systems. *Forests* **2022**, *13*, 829. https://doi.org/ 10.3390/f13060829

Received: 4 May 2022 Accepted: 20 May 2022 Published: 26 May 2022

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