International agreements combined with the recent Chilean Forestry Policy (2015–2035) represent a challenge and an opportunity for forest landscape restoration in Chile. Nevertheless, restoring over 500,000 ha using mainly native species seems like a daunting task by 2035. Here, we discuss the three major bottlenecks that currently constrain the restoration efforts of forest ecosystems in Chile. First, Chile urgently needs a national strategic plan for forest landscape restoration, which should take into account mid‐ and long‐term goals. There is also a need to prioritize resource allocation for efficient use, promoting the creation of economic subsidies for restoration that consider different types of forest ecosystems. Second, there is a great need for better nursery protocols in plant production as well as to strengthen educational programs for professional and technical training, given the lack of high‐quality personnel in Chilean nurseries. This would help increase the currently limited national plant supply, improving quality and increasing the diversity of native species suitable for forest restoration. Lastly, taking advantage of novel eco‐technological tools and promoting innovative plantation design would help to overcome the usually deficient results in the establishment phase, leading to higher survival rates and promoting better performance of native species. Beyond current experiments that are relatively efficient on a small spatial scale, the practice of forest restoration needs to become massive and successful at a landscape scale. More and better applied research is crucial for improving the impact of forest landscape restoration, so that Chile can achieve its forest restoration challenge in the next decade.

Differences in water-acquisition strategies of tree root systems can determine the capacity to survive under severe drought. We evaluate the effects of field water shortage on early survival, growth and root morphological variables of two South American Mediterranean tree species with different rooting strategies during two growing seasons. One year-old Quillaja saponaria (deep-rooted) and Cryptocarya alba (shallow-rooted) seedlings were established under two watering treatments (2 L·week⁻¹·plant⁻¹ and no water) in a complete randomized design. Watering improved the final survival of both species, but the increase was only significantly higher for the shallow-rooted species. The survival rates of deep- and shallow-rooted species was 100% and 71% with watering treatment, and 96% and 10% for the unwatered treatment, respectively. Root morphological variables of deep-rooted species such as surface area, volume, and diameter were higher under unwatered treatment. On the other hand, shallow-rooted species had a higher total root dry mass, length, surface area with watering treatments. Our findings suggest that deep-rooted species are highly recommended for reforestation in dry conditions, even under low soil water availability. Water supplements during the summer season can attenuate the differences between deep- and shallow-rooted species in their ability to survive drought during the early stage.

Drought-avoidance traits of South American Mediterranean tree species are crucial attributes to be considered in nursery practices aimed at improving the performance of seedlings exposed to intense summer drought in dryland reforestation projects. In this study, we determined the relation between nursery fertilization doses and the development of drought-avoidance traits of the soapbark tree Quillaja saponaria (Mol.) under contrasting watering regimes following post-planting. Seedlings were grown for 6 months using four increasing doses of controlled-release fertilizer (0, 3, 6, and 12 g L-1 of Basacote® Plus 15:8:12). After outplanting, half of the seedlings were watered weekly and the other half were left unwatered for one growing season from September 2011 to May 2012. Seedlings were periodically measured for morphological and ecophysiological parameters, and carefully harvested for root measurements at the end of the study. Our results showed that high fertilization doses produced significantly larger seedlings in the nursery with high nitrogen and phosphorous foliar concentrations, which resulted in a significantly higher shoot dry mass after outplanting. Unfertilized seedlings grown with water application had a significantly higher stem diameter, root dry mass and lower shoot/root compared with seedlings with high fertilizer dose. These results highlight the ability of this species to maintain drought-avoidance traits, such as high xylem water potential and chlorophyll fluorescence, during the first 3 months of the 7-month drought period. High nutrient loading, although resulting in improved shoot productivity after outplanting, did not make a significant contribution to the early development of drought-avoidance traits in Q. saponaria.

The size of a container determines the development and quality of root systems. In the case of taprooted forest species used for dryland reforestation, deeper containers may favour early root development and, consequently, better soil profile colonization after outplanting. Although research on container design for worldwide tree species has been developed in the last decades, technical solutions for containerized forest species with a taproot system have been poorly documented. We present a case study using Acacia caven (Mol.) Mol., which has fast-growing taproots and long lateral and superficial roots. The aim of this study is to evaluate the effects of different containers on rooting volume in the early morphological development of A. caven seedlings. Ten day-old seedlings were cultivated in five different PVC container types varying in volume, width and length (T440-Short, T440-Long, T880-Short, T880-Long, and T440-C), in a completely randomized design for one growing season. At the end of the study, whole seedling samples were destroyed to assess taproot length, lateral root biomass, and total root/shoot dry biomass. To evaluate the potential plant capacity for developing new roots, a subsequent experiment using the root growth potential test was performed successfully. Results showed that change in root volume distribution (short vs. elongated containers) had the greatest influence on seedling quality, whereas the size of container (small volume vs. large) was of minor importance. Elongated containers (35 cm to 40 cm in length) with self-pruning basal roots produced seedlings with smaller shoot/root ratios, longer root systems, and a greater ability to restart new root growth in deeper container strata. Elongated containers also prevented taproot deformation. The present study suggests that it would be appropriate to rethink container design for seedlings of deep-rooted xerophytic species destined for water-limited transplanting conditions.