Chestnut Growth Research Articles

Delineating the genetic variability, inter-relationship and morphological variations in water chestnut for nut yield and mineral composition

The fresh, edible fruit-nut of the water chestnut, an annual herb found in water, is an important aquatic crop. There is an enormous variation in water chestnut growth and yield, which is not extensively recorded in India. The yield performance of 23 water chestnut lines was examined in the present investigation. Crop variability contributes to the effective application of plant characteristics in the creation of stable and productive cultivars. The present study was conducted in 2020-2021 on water chestnut (Trapa spp.) accessions in order to assess the degree of genetic variability and yield character relationships. The genotypic coefficient of variation and heritability estimations were high for Zn, Mn and Fe content in rind, number of spines per nut, pedicel length, 10 dried nut rind weight, number of leaves per plant, number of nuts per plant, leaf length and fresh nut yield per plant. The following traits showed low heritability estimates and genotypic coefficients of variation: leaf width, nut pedicel length, weight of a single fresh nut, weight of a single shelled nut, and TSS. Fresh nut yield per plant was positively and significantly associated with the number of leaves per plant and the weight of 10 fresh nuts. To improve fruit-nut yield in water chestnut, selection criteria such as number of leaves per plant, number of nuts per plant, fruit pedicel length, fresh nut weight, TSS, 10 fresh nut weight and 10 fresh nut rind weight could be applied in different crop improvement programmes of water chestnut.

Omitting the Application of Nitrogen or Potassium Reduced the Growth of Young Chestnut (Castanea sativa) Trees, While a Lack of Boron Decreased Fruit Yield

The chestnut tree (Castanea sativa Mill.) is gaining importance in the mountainous regions of southern Europe due to the high value of its fruits. It is essential to establish effective cultivation protocols, considering that this species is still relatively understudied. In this study, we present the outcomes of the initial establishment of a chestnut orchard conducted through a nutrient omission trial for four years. The treatments included a fertilization plan with nitrogen, phosphorus, potassium, and boron (NPKB), the control, and four other treatments corresponding to the omission of each nutrient (-NPKB, N-PKB, NP-KB, NPK-B). The -NPKB and NP-KB treatments showed significantly lower trunk circumferences and canopy volumes compared to the other treatments. The NPK-B treatment resulted in the lowest fruit production, with a total accumulated yield (2020–2022) of 0.56 kg tree–1, a value significantly lower than that of NPKB (1.12 kg tree–1) and N-PKB (1.19 kg tree–1). The assessment of nutrient concentrations in the leaves revealed plants with deficient levels of B and K in treatments that did not receive these nutrients. Conversely, N levels in the leaves in the -NPKB treatment fell within the sufficiency range (20 to 28 g kg–1). This suggests that the sufficiency range should be adjusted to higher values, given the treatment’s effect on tree growth. It was also observed that the -NPKB treatment led to lower soil organic matter compared to the other treatments, likely due to reduced herbaceous vegetation development under the canopy, leading to decreased organic substrate deposition in the soil. The main findings of this study are that N and K were crucial elements for the optimal growth of chestnut trees, while B played a significant role in fruit production.

The ectomycorrhizal fungus Paxillus involutus positively modulates Castanea sativa Miller (var. Marsol) responses to heat and drought co-exposure

Castanea sativa Miller, a high-valuable crop for Mediterranean countries, is facing frequent and prolonged periods of heat and drought, severely affecting chestnut production. Aiming to tackle this problem, this study unraveled the influence of mycorrhizal association with the fungi Paxillus involutus (Batsch) on young chestnut plants' responses to combined heat (42 °C; 4 h/day) and drought (no irrigation until soil moisture reached 25%) over 21 days of stress exposure. Heat stress had no harmful effects on growth, photosynthesis, nor induced oxidative stress in either mycorrhizal (MR) or non-mycorrhizal (NMR) chestnut plants. However, drought (alone or combined) reduced the growth of NMR plants, affecting water content, leaf production, and foliar area, while also hampering net CO2 assimilation and carbon relations. The mycorrhizal association, however, mitigated the detrimental effects of both stresses, resulting in less susceptibility and fewer growth limitations in MR chestnut plants, which were capable of ensuring a proper carbon flow. Evaluation of the oxidative metabolism revealed increased lipid peroxidation and hydrogen peroxide levels in NMR plants under water scarcity, supporting their higher susceptibility to stress. Conversely, MR plants activated defense mechanisms by accumulating antioxidant metabolites (ascorbate, proline and glutathione), preventing oxidative damage, especially under the combined stress. Overall, drought was the most detrimental condition for chestnut growth, with heat exacerbating stress susceptibility. Moreover, mycorrhizal association with P. involutus substantially alleviated these effects by improving growth, water relations, photosynthesis, and activating defense mechanisms. Thus, this research highlights mycorrhization's potential to enhance C. sativa resilience against climate change, especially at early developmental stages.

Genome-wide identification, evolution, and expression analysis of the NAC gene family in chestnut (Castanea mollissima)

The NAC gene family is one of the most important transcription factor families specific to plants, responsible for regulating many biological processes, including development, stress response, and signal transduction. However, it has not yet been characterized in chestnut, an important nut tree species. Here, we identified 115 CmNAC genes in the chestnut genome, which were divided into 16 subgroups based on the phylogenetic analysis. Numerous cis-acting elements related to auxin, gibberellin, and abscisic acid were identified in the promoter region of CmNACs, suggesting that they play an important role in the growth and development of chestnut. The results of the collinear analysis indicated that dispersed duplication and whole-genome-duplication were the main drivers of CmNAC gene expansion. RNA-seq data of developmental stages of chestnut nut, bud, and ovule revealed the expression patterns of CmNAC genes. Additionally, qRT-PCR experiments were used to verify the expression levels of some CmNAC genes. The comprehensive analysis of the above results revealed that some CmNAC members may be related to chestnut bud and nut development, as well as ovule fertility. The systematic analysis of this study will help to increase understanding of the potential functions of the CmNAC genes in chestnut growth and development.

Comparative growth and physiological performance of American chestnuts, oaks, hickories, and sugar maple across a silvicultural gradient in overstory retention

The development of a blight-tolerant transgenic American chestnut (Castanea dentata (Marsh.) Borkh.) would provide the potential for reintroducing this species into forests it historically dominated. However, we lack a silvicultural understanding of the environmental conditions most favorable to the growth and survival of American chestnut relative to species with which it historically co-existed. We examined effects of shelterwoods with variable residual densities on the growth and physiology of blight-tolerant chestnut seedlings relative to sugar maple (Acer saccharum Marsh.), and several oak (Quercus spp.) and hickory (Carya spp.) species across a broad range of light availabilities (gap light index; GLI; of 4–50%). To assess the hypothesis that American chestnuts are more physiologically plastic and responsive to light than oaks and hickories, we measured seedling relative diameter and height growth rates and photosynthetic light-response curves across a GLI gradient. The diameter and height growth of chestnut increased with GLI, while oaks and hickories did not. All species varied aspects of their photosynthetic physiology across the GLI gradient in an approximately equivalent manner; the dark respiration rate and light compensation point increased equivalently across species in response to increases in light availability. A multivariate analysis identified three major axes of variation across ten measured traits, largely reflecting differences in species averages and phenotypic plasticity across the GLI gradient. American chestnut seedlings were spread across these multivariate dimensions more than other species, consistent with the hypothesis of higher phenotypic plasticity in this focal species. These results suggest that low residual shelterwood densities may better promote the establishment of underplanted chestnut seedlings relative to associated tree species provided it does not result in detrimental increases in the productivity of competing understory species.

Eight-year field performance of backcross American chestnut (Castanea dentata) seedlings planted in the southern Appalachians, USA

The American chestnut (Castanea dentata) is imperiled due primarily to two diseases caused by nonnative pathogens, notably chestnut blight and Phytophthora root rot (PRR) caused by Cryphonectria parasitica and Phytophthora cinnamomi, respectively. Field reintroduction trials are important to test trees bred for blight resistance under forest conditions to quantify survival and field performance in managed stands that represent future restoration sites. We planted 513 pedigreed bare-root (1–0) nursery seedlings into an even-aged regeneration harvest in the Blue Ridge Mountains of eastern Tennessee, USA to test effects of breeding, genetics, and seedling size class on field performance, including survival, total growth, incremental growth (a measure of growth efficiency), and height growth patterns. Mortality was highest in the first two years after planting, and PRR symptoms coupled with soil and root assays that tested positive for P. cinnamomi suggested this disease was a significant contributor to mortality. Chinese chestnut (C. mollissima), known to be resistant to P. cinnamomi and C. parasitica, had the highest survival (96 percent) compared to American chestnut (34 percent) and hybrid generations, including the BC3F3 generation (41 percent). Less advanced hybrid generations, such as the BC1F3 and BC2F3, had the greatest total height and ground-line diameter (GLD) and height growth efficiencies. BC3F3 generation seedlings were associated with higher-than-expected rates of nominal height growth patterns (i.e., flat growth rates over time or early mortality) compared to Chinese chestnut seedlings. Results, however, indicated the breeding program was successfully integrating desired American chestnut growth traits into the hybrid genome while transferring an intermediate level of resistance from the Chinese chestnut. We identified superior and inferior BC3F3 families that can help inform breeding and restoration efforts. Visually grading seedlings before planting affected survival and growth of generations and genetic families differently, indicating that refinement of nursery production and restoration plantings should consider genetic effects. Across generations, seedling size grading improved total height and GLD growth that would save resources necessary for competition control and animal browsing protection, but large-size seedlings also exhibited lower C. parasitica resistance rankings over time, probably owing to earlier bark fissuring. PRR probably affected outcomes, particularly for hybrid and American chestnut seedlings that have very low levels of P. cinnamomi resistance. Managers could expect advanced breeding generations to perform similarly to American chestnut in growth through the critical stage of early stand development. More durable resistance to C. parasitica and mitigation of PRR through better site selection and/or resistance screening will improve future restoration efforts.

Mixed Castanea sativa plantations including arboreal companion species enhance chestnut growth and high-quality timber production

ContextChestnut (Castanea sativa Mill.) is an important tree species for its timber, which is widely used for multiple purposes, including the veneer industry. The species has an interesting productive potential in Chile and requires specific management strategies to produce valuable, high-quality logs. Although mixed plantations including companion species usually enhance timber quality of several trees, the performance of chestnut under different associations is not well known. AimsThe objective of this study was to assess growth, survival, health, and timber quality of chestnut trees in several plantation types, including monoculture and mixtures with other companion trees and/or shrub. MethodsGrowth and survival measurements were taken periodically in pure chestnut and mixed plantations established in southern Chile for a 20-year period after planting. The mixed plantations tested were: a main forest species mixture (Castanea sativa Mill., Quercus rubra L., Quercus robur L. and Prunus avium L.); three mixtures including main forest species plus one arboreal companion species (Alnus glutinosa L., Gevuina avellana Mol. or Embothrium coccineum J.R. Forst. & G. Forst.); one including main forest species plus one shrub nurse species (Fabiana imbricata Ruiz & Pav.); and three mixtures including one of the arboreal companion species and the shrub. Timber quality variables were assessed at age 20, and health status was recorded at ages 7 and 20 in all plantations. Growth variables were analyzed using linear mixed models to assess plantation effect over time. Kaplan-Meier survival analysis and Log Rank Test were used to compare chestnut tree survival among plantation types. Quality timber variables were analyzed with a χ2 test. ResultsChestnut trees associated with arboreal main species (P. avium, Q. rubra, Q. robur) (Mix1) showed the best performance, with 10.1 % and 8.3 % higher height than average values of the other mixtures and the monoculture, respectively, and 19.1 % and 12.8 % higher diameter growth than across plantation types and monoculture average values, respectively. Mix1 had the highest average volume per tree (0.34 m−3), at least 30 % higher than the average volume of pure and other mixed plantations. This mixture including only main species also exhibited the highest percentage of trees with high trunk length values of all plantation types. No pest or diseases were recorded on chestnut trees, and survival was high in all plantation types. ConclusionThe impact of mixed plantations on growth and timber quality was evidenced at age 20. In particular, the association including arboreal companion species enhanced chestnut tree performance.

Stem Growth of Horse Chestnut (Aesculus hippocastanum L.) under a Warming Climate—Tree Age Matters

This research provides new information about the effect of drought on horse chestnut growth (Aesculus hippocastanum L.) in different ages. Global climatic scenarios predict a higher frequency of heatwaves and drought periods; however, investigations into the growth reaction of horse chestnut to drought are completely lacking. Approximately 50-year-old solitary, 100-year-old solitary, and 100-year-old canopy horse chestnut trees in a floodplain area were investigated. Growth reactions measured using automated dendrometers with respect to meteorological variables and water table depth were investigated during the years 2019–2021. Cambial activity was shown to be driven by tree age, as younger trees had higher stem radial increment rates. Both mature tree groups suffered from a low depth of water level and from higher sensitivity to meteorological variables, as growth was limited when mean daily vapor pressure deficit (VPD) exceeded 600 Pa. Together with a lower probability of growing days and a shorter growing season (GS) with earlier cessation of growth resulted in a lower total year radial increment (GRO) and basal area increment (BAI) when compared to younger trees. The young trees also exhibited lower tree-water-deficit-induced stem shrinkage (TWD) across all the studied years. Overall, horse chestnut trees in this floodplain area could be endangered by the decreasing level of soil water, with a greater age exacerbating the effects of drought. The year water deficit exceeded −340 mm in this locality every year, which has to be compensated for by regular flooding.

Growth of chestnut and tea seedlings under different root partitioning patterns

Growth of chestnut and tea seedlings under different root partitioning patterns

Effects of Temporal Dynamics, Nut Weight and Nut Size on Growth of American Chestnut, Chinese Chestnut and Backcross Generations in a Commercial Nursery

Blight-resistant American chestnut (Castanea dentata) may soon be commercially available, but few studies have tested methods to produce high quality seedlings that will be competitive after planting. This study evaluated the performance of one American, one Chinese (C. mollissima), one second-generation backcross (BC3F2), and 10 third-generation backcross chestnut families (BC3F3). We examine growth over one year in a commercial tree nursery in east Tennessee. We examined relationships among nut size and weight and seedling growth, between germination timing and seedling survival, and between germination percentage and growth. Across the population tested, a 1 g increase in nut weight corresponded to a 6 cm increase in seedling height, a 0.5 mm increase in root collar diameter and one additional first order lateral root, but models had low predictive power. BC3F3 chestnuts grew similarly to American chestnuts, with substantial differences in growth among chestnut families within generation. Nuts that germinated by 23 April had greater than 1955 odds of surviving the first growing season than nuts that germinated in late May. American and backcross chestnut growth slowed in late June, presumably due to exhaustion of their cotyledons before leaf expansion. These results will help nursery managers refine cultural practices to maximize growth of backcross chestnuts.

Four-year response of underplanted American chestnut (Castanea dentata) and three competitors to midstory removal, root trenching, and weeding treatments in an oak-hickory forest

American chestnut (Castanea dentata) has been killed or reduced to recurrent stump sprouts throughout its range following the importation of multiple pathogens in the 19th and early 20th centuries. Understanding what drives chestnut growth and survival would aid the development of appropriate silvicultural guidelines for restoring the species once blight resistant stock is available. Here we compare the response of planted American and hybrid chestnut seedlings to that of important competitors, northern red oak (Quercus rubra), sugar maple (Acer saccharum) and red maple (A. rubrum), under treatments designed to evaluate the effects of various sources of competition on seedling growth and survival. After four years, American and hybrid chestnut was significantly taller in trenched plots (181.8±12.4cm; mean±SE) compared to untrenched plots (127.5±7.9cm), weeded plots (174.5±12.7cm) compared to unweeded plots (130.1±6.5cm) and in midstory removal plots (156.6±7.8) versus full canopy (88.8±11.7cm), and had outperformed the other species in most competitive environments. Chestnut was the only species to respond to every treatment with significant growth increases, displaying a notable ability to capture growing space when it became available. We suggest that American chestnut restoration may be more successful where early stand management provides chestnut a brief period of reduced competition. Specifically, midstory removal can increase survival and growth of underplanted American chestnut, and when combined with multi-stage shelterwood removals of the overstory and some amount of competition control, may constitute a viable restoration strategy for chestnut in many of the eastern oak-hickory forests where it was originally dominant.

American Chestnut Growth and Survival Five Years after Planting in Two Silvicultural Treatments in the Southern Appalachians, USA

The ability to restore American chestnut (Castanea dentata) through the planting of blight-resistant (Cryphonectria parasitica) trees is currently being tested. Forest-based research on the species’ silvicultural requirements and chestnut blight development are lacking. Pure American chestnut seedlings were planted in a two-age shelterwood forest with low residual basal area and in a midstory-removal treatment with high residual basal area. Survival did not differ between silvicultural treatments and averaged 67 percent across both treatments by the fifth year. Trees in the two-age shelterwood were 2.36 m and 16.8 mm larger in height and ground-line diameter, respectively, compared to trees in the midstory-removal by the fifth growing season. Blight occurrence was not affected by silvicultural treatment. Exploratory analyses indicated that seedling grading at planting and keeping trees free-to-grow through competition control would have resulted in a two-year gain in height and GLD growth in the two-age shelterwood treatment. The two-age shelterwood represented the most efficacious prescription for chestnut restoration, but the midstory-removal prescription may offer a reasonable alternative in areas where harvesting must be delayed.

Foliar application of Sili-K® increases chestnut (Castanea spp.) growth and photosynthesis, simultaneously increasing susceptibility to water deficit

The beneficial effects of Si have mainly been observed in herbaceous plants, while little is known about its role in deciduous trees. The aim of this work was to evaluate the effect of foliar application of Si on chestnut leaf growth, photosynthesis and water relations in the presence of short, but intense water deficit. Sili-K® solution (containing 0.12 % Si and 0.15 % K) was repeatedly (× 3) sprayed onto leaves of potted chestnut plantlets and irrigation was suspended 7 weeks later, for 8 days. Leaf growth, anatomy, as well as physiological and biochemical traits of the plantlets were studied. Si application enhanced chestnut growth, due to increased photosynthetic traits, including higher chlorophyll content and chlorophyll a to b ratio, photochemical efficiency of PSII, gas exchange (stomatal conductance, transpiration rate, net CO2 assimilation) and oxygen evolution rate. Meanwhile, Si yielded larger and thinner leaves, higher xylem, specific leaf area and transpiration rate, thus being beneficial to the tree in absorbing sunlight energy for photosynthesis and in alleviating heat stress. However, Si also lowered leaf sap osmotic pressure, causing the plant to lose water more quickly, thus being more susceptible to water stress. Si improved chestnut photosynthesis, growth, and heat stress tolerance, but it also increased the susceptibility to drought.

Short Communication - A Likely Virus Was Observed from Chinese Chestnut

Chestnut is one of popular dry fruit due to its rich nutrients, flavor, taste and unique antioxidant activity in the world. Blight canker symptom is one of the serious problems for Chestnut growth and preservation. At present, fungi and parasite are regarded as the dominant roles for blight canker. A kind of likely virus was observed accidentally from Chinese chestnut by electron microscope. Virus might be another reason for blight canker. Little information is available referring to virus from Chinese chestnut presently. The primary shape observed by electron microscope was introduced in this paper. The isolation, identification, and characters of this virus analogue is in progress and further investigated.

Influence of climate, edaphic factors and tree nutrition on site index of chestnut coppice stands in north-west Spain

The relationships between climatic variables, soil parameters, tree nutrition and site index (SI) were examined in 30 chestnut coppice stands in Asturias, the region with the largest area of chestnut coppice in north-west Spain. SI was estimated from a top height projection equation for this species. A soil sample was obtained at 0- to 20-cm depth and several leaves were collected from the upper zone of the dominant trees in each plot for further analysis. Chi-square automatic interaction detection and parametric regression techniques were used to determine the key factors affecting SI. According to the regression tree and the parametric regression model for all variables, the extractable Mg in the soil and mean temperature of the warmest month were the most important variables explaining SI in the region. Elevation and foliar concentrations of phosphorus were not significant factors in the parametric regression analysis (although considered key factors when foliar nutrients and physiographical variables were analysed separately). The results show the importance, for chestnut growth, of site selection and balanced fertilizer treatment consistent with the soil requirements of the species.

English

The use of SMCRA approved practices for mined land reclamation has resulted in arrested succession throughout many areas of central Appalachia. The combination of heavily compacted soils and the addition of aggressive, often non- native, grasses and forbs creates an environment characterized by high soil bulk density and aggressive ground-layer competition. This results in a situation where trees are unable to recruit and thus many lands are unable to return to original forest cover through natural processes of succession. Using the basic principles of the Forestry Reclamation Approach (FRA), we report on two experiments conducted in Ohio: one designed to remediate a 30-yr arrested succession and the other designed to encourage immediate reforestation at the time of reclamation. We conducted these experiments using American chestnut (Castanea dentata) to explore the potential for using these sites as part of the national restoration plan under development by the American Chestnut Foundation (ACF). The first experiment utilized deep soil ripping and a combination of plowing and disking treatments. After three years, the results are clear. Simply planting chestnut into untreated existing habitat is ineffective. Some type of surface treatment to reduce soil bulk density and competition is necessary for seedling establishment. The more significant the disturbance, the better the survival and growth of chestnut. The second experiment utilized loose end-dumping at the time of reclamation. Various methods of chestnut deployment and planting were evaluated including direct seeding and bare-root seedlings. Plantings were done with and without protection from predators in different microsites. While survival of seedlings was greater than seeds, the most noticeable enhancement to survival was the addition of a tree shelter, which nearly doubled the survival rate. In summary, American chestnut appears to thrive on mine land reclamation sites—this may prove to be a useful focal point for restoration of the species while aiding in the reforestation of old and new reclamation sites.

ECOPHYSIOLOGICAL CHARACTERIZATION OF C. SATIVA TREES GROWING UNDER DIFFERENT ALTITUDES

The aim of this work was to compare chestnut growth (cv. Judia) during the year of 2007 at different altitudes (450, 600, 700, 850 and 1050 m a.s.l.). Concerning daily mean photosynthesis rate, highest rate was measured at 1050 m a.s.l., 21.8°C, 11.3 μmol.CO 2 .m -2 .s -1 , and the lowest one was 7.6 μmol.CO 2 .m -2 .s -1 determined in the lowest altitude (29.5°C). Data also indicates a variation in photosynthetic pigment composition, showing an increase in Chla/Chlb from 3.1 to 3.7, respectively at 1050 and 450 m a.s.l. Contrarily a deacrease in Chl/Car was observed. Moreover, unsaturation index increased as an altitude manner. while lipid peroxidation increased with the altitude. Leaf water potential, increased from 450 m a.s.l., -1.4 MPa, to 1050 m a.s.l., -0.81 MPa. Highest fruit size was found at 700 m a.s.l. with 50 fruits/kg, but it must be underlined that percentage of aborted fruits increased for altitudes above the 600 m a.s.l. from 20 until 100% yielded in the 1050 m a.s.l. orchard and below 600 m a.s.l., being 70%.

Impact of fertilization on chestnut growth, N and P concentrations in runoff water on degraded slope land in South China

Growing fruit trees on the slopes of rolling hills in South China was causing serious environmental problems because of heavy application of chemical fertilizers and soil erosion. Suitable sources of fertilizers and proper rates of applications were of key importance to both crop yields and environmental protection. In this article, the impact of four fertilizers, i.e., inorganic compound fertilizer, organic compound fertilizer, pig manure compost, and peanut cake (peanut oil pressing residue), on chestnut (Castanea mollissima Blume) growth on a slope in South China, and on the total N and total P concentrations in runoff waters have been investigated during two years of study, with an orthogonal experimental design. Results show that the organic compound fertilizer and peanut cake promote the heights of young chestnut trees compared to the control. In addition, peanut cake increases single-fruit weights and organic compound fertilizer raises single-seed weights. All the fertilizers increased the concentrations of total N and total P in runoff waters, except for organic compound fertilizer, in the first year experiment. The observed mean concentrations of total N varied from 1.6 mg/L to 3.2 mg/L and P from 0.12 mg/L to 0.22 mg/L, which were increased with the amount of fertilizer applications, with no pattern of direct proportion. On the basis of these experiment results, organic compound fertilizer at 2 kg/tree and peanut cake at 1 kg/tree are recommended to maximize chestnut growth and minimize water pollution.

English

Mine reclamation sites can be difficult to reforest, and trees that successfully establish on these sites are often comprised of relatively undesirable species. American chestnut (Castanea dentata) once dominated the forests throughout much of the coal-producing region in Appalachia. However, the exotic fungus Cryphonectria parasitica was discovered in 1904 and within several decades, the blight killed nearly every tree throughout the range. A dedicated breeding program sponsored by The American Chestnut Foundation has made tremendous progress toward producing a blight-resistant variety of American chestnut by hybridizing with the blight-resistant Chinese chestnut (Castanea mollissima). It is expected that a blight-resistant hybrid chestnut tree (~94% American chestnut) will be available for reintroduction within the next decade, providing a new species option for reclamation programs. Due to continued presence of the fungus throughout eastern forests, few studies have examined American chestnut growth performance in plantations. However, a recent study on a blight-free site in Wisconsin reported exceptional growth capacity of chestnut relative to co-occurring hardwood species. Sufficient evidence also exists to suggest that American chestnut may tolerate many of the stressful physical and chemical soil characteristics typical of mine reclamation sites. Rapid growth, adaptability to a wide range of environmental conditions, good timber quality, and exceptional wildlife properties make American chestnut a highly desirable potential species for future reclamation programs.

Growth of chestnut (Castanea sativa) in the Netherlands

European interest in relatively fast growing trees that will produce durable timber has increased strongly in recent years for economic and ecological reasons. Agriculture needs alternative products and production systems. Growing quality timber, possibly combined with another crop is one way of doing this. It would result in fewer imports from tropical forests and reduce the requirement for chemical preservatives. In new afforestation, fast growing trees are commonly planted with little attention being paid to the quality of the timber. Since small diameter trees can be used with modern gluing techniques, deciduous hardwood species grown on relatively short rotations, such as Robinia pseudoacacia L., Prunus avium L. and Castanea sativa Mill., can now be used. Knowledge about possibilities and limitations of these species for short (20—40 years) rotations is as yet incomplete. To obtain an insight into the potential of Castanea sativa in the Netherlands, an inventory was carried out. Castanea sativa was probably introduced by the Romans and is found over the whole country. It mainly occurs as solitary trees and in mixture with other species