Robinia pseudoacacia L. Plantation in Erosion Control
Areas of Artvin Region, Turkey
Z. ÖLMEZ1*, T. YÜKSEK1, and S. AYAN2
1Kafkas University, Artvin Faculty of Forestry, Artvin TURKEY
2Gazi University, Kastamonu Faculty of Forestry, Kastamonu TURKEY
*Corresponding Author: Z. Ölmez, Kafkas University, Artvin Faculty of Forestry, 08000 Artvin, TURKEY, E-mail:
ABSTRACT
The aim of this study is to determine diameter of root collar growth and height of Robinia pseudoacaia L. seedlings planted in 2000 in erosion control area located in the southeastern of Artvin, Turkey. Three sample plots, each with three replications of 30 seedlings planted in it, were chosen out of the 552 ha erosion control area. At the end of the third growing season, height and root collar diameter of the seedlings were measured. In addition, both aspect and slope locations of the sample plots were also determined. The inclination of sample plots was approximately the same. Effects of the exposure and shape location of slope on growth of the seedlings were investigated. Results show that the exposure and location of slope affected the heights and root collar diameters of the seedlings.
Key words: Robinia pseudoacacia L., erosion, plantation
INTRODUCTION
The original natural range of (Robinia pseudoacacia L.) black locust is in two sections: 1) the central Appalachian Mountains from central Pennsylvania and southern Ohio south to northeastern Alabama, northern Georgia, and northwestern South Carolina, and 2) the Ozark Plateau of southern Missouri, northern Arkansas, northeastern Oklahoma, and the Oachita Mountains of central Arkansas and southeastern Oklahoma. Outlying populations thought to be part of the original natural range occur in southern Indiana, Illinois, Kentucky, Alabama, and Georgia (Anonymous, 2004).
Black locust has been successfully planted in almost every state. Naturalized populations occur throughout the United States, southern Canada, Europe, and Asia (Huntley, 1990; Anşin and Özkan, 1993).
Black locust reaches sexual maturity at approximately 6 years of age. The best seed production occurs between 15 and 40 years of age. Seed production continues until about age 60. Good seed crops are produced every 1 to 2 years (Huntley, 1990). Seeds are hard and require scarification for germination to take place (Yahyaoğlu and Ölmez, 2003).
Seedlings established on good sites that are free of competition show rapid early growth (Huntley, 1990). Black locust can grow on a wide range of sites, but grows best on rich, moist, limestone-derived soils. It does not, however, do well on heavy or poorly drained soils, although it appears to be tolerant of some flooding. Surface-mined lands that are otherwise unproductive may produce good economic returns if planted for short-rotation, woody biomass fuels. Black locust may be productive for this purpose, since it exhibits rapid early growth and sprouts after cutting (Toplu, 2000; Anonymous, 2004). Black locust is planted in shelterbelts, as an ornamental, for nectar production for honey, and for fuel (Keresztesi, 1980).
The popularity of black locust for reforestation and revegetation of mined lands in the United States is waning, primarily because of its weedy habit and locust borer infestations. Herbaceous perennials are more often selected for reclamation. It is still widely planted, however, and as of 1984 there were over one million hectares of black locust plantations worldwide (Anonymous, 2004).
Black locust increases soil nitrogen through relatively high rates of nitrogen fixation and accretion (Montagnini et al., 1991). Acetylene reduction rates (indicating nitrogen fixation) have been determined for nodulated black locust roots. A heavy litter layer is created early in stand development. The litter is subject to rapid decomposition, improving soil structure and fertility (Anonymous, 2004).
On acidic mined sites, black locust performance is improved by additions of lime to increase soil pH (Hensley and Carpenter, 1986). Black locust plantings can be inoculated with Rhizobium bacteria specific to black locust for improved performance. Black locust plantation failures have been attributed to poor site conditions, including eroded, compacted, or clayey soils, low soil fertility, and locust borer infestations (Huntley, 1990; Toplu, 2000). Black locust planted on poor soils (such as mine spoils) is often subject to locust borer infestations that severely affect form and vigor (Boring and Swank, 1984).
Black locust is grown in many countries including Hungary, Bulgaria, Germany and Turkey for a long time. In its natural distribution areas, annual precipitation ranges between 400 and 1500 mm, annual mean temperature is between 2 and 38 ºC and soil pH changes between 4.6 and 8.2 (Keresztesi, 1988).
Recent estimations shows that there is approximately 20.7 million ha forested area in Turkey, covering 25.8% of the total land area. However, little over half of this forested area is classified as unproductive (51.9% or 10.7 million ha) (Gümüş, 2000). It has been suggested that a country should have at least 30% of its total land area covered with forests in order to support its people’s need of forest products (Genç, 1992).
According to Ürgenc and Boydak (1985), about 10 million ha area is in need of reforestation in Turkey and there is about 154.000 ha degraded forested area only in the Artvin region. Thus, there is an urgent need of afforestation and erosion control efforts in these areas. So far, such efforts were done in only 14.500 ha area where mostly black locust and oak (Quercus petrea) and few Scotch pine (Pinus silvestris), caper bush (Capparis ovata), and walnut (Juglans regia) seedlings were planted (Göktürk et al., 2004).
The aim of this study is to determine growth of black locust seedlings planted in erosion control area located in the southeastern of Artvin, Turkey.
MATERIAL AND METHODS
The study area, Asagi Maden Village (Latitude: 40º 56' 57'' N, Longitude: 41º 47' 44'' E, h: 750-1400 m), is at the southern part of Artvin.
Height and diameter of root collar of black locust seedlings planted in three sample plots were measured. Besides, physiographic characteristics of the sample plots such as exposure, slope, and altitude were defined. Nine soil pits were dug in each sample plots and soil samples were taken at two different depths, 0-20 cm and 20-40 cm. Mechanical analyses and pH were conducted on each soil sample. The size of erosion control area was 552 ha and the plantation studies were able to be carried out 250 ha of the area because of the fact that the other 302 ha of the area was rocky and there was no soil.
The research was done on 3 different sample plots with three replications each consisting of 30 seedlings. The sample plots were located on the south-eastern, south-western and eastern exposures.
RESULTS AND CONCLUSION
Mean height and root collar diameter values of the seedlings and some soil properties of sample plots were shown in Table1 and Table 2, respectively. Soil type of the study area was mostly sandy clay loam (SCL) and soil pH was between 6.67 and 7.84 (Table 2). Mean inclination on the area was approximately 70%. Soil depth in the area was estimated to be between 30 and 80 cm.
Annual precipitation was measured as 645 mm while mean temperature was reported as 13.7 ºC by the Artvin Meteorological Station, positioned as the nearest to the research area (Kılıç and Kurtulus, 1994).
Survival rate of the seedlings ranged between 85-90% at the end of the third growing season. The maximum average of seedling height (179.2 cm) and the minimum average of seedling height (65.7 cm) were obtained on the sample plots (Table 1). The height and root collar diameter growth of seedlings were the highest in the eastern exposure (Table 3).
Results from the statistical analyses (ANOVA tables and Newman Keuls tests) are listed in Table 3 showing the relationships on the effects of the exposure and location of slope with the height and root collar growth of black locust seedlings at 0.05 significance level. When the relationship between location of slope and the height and root collar diameter of the seedlings were considered, the maximum height (123.3 cm) and root collar diameter (17.8 mm) were obtained on the lower parts of slope (Table 3). In general, both soil depth and plant nutrient elements were higher in lower parts of slopes than upper parts (Çepel, 1995). This explains the fact that black locust seedlings showed better growth in the lower location than the others on the research area.
There are many degraded forest areas (about 154000 ha) in the Artvin region of Turkey. Results of this study showed that Black locust grew well in these areas, suggesting that this species is suitable for such degraded areas and may be well incorporated with future erosion control efforts in the region.
REFERENCES
Anonymous, 2004. Index of species information, Species: Robinia pseudoacacia.
www.fs.fed.us/database/feis/plants/tree/robpse/ 15 July 2004.
Anşin R., Özkan Z.C., 1993. Tohumlu bitkiler (Spermatophyta). KTU Orman Fakültesi, Yayın No: 19, Trabzon.
Boring L.R., Swank W.T., 1984. The role of black locust (Robinia pseudoacacia) in forest succession. Journal of Ecology, 72 (3), 749-766.
Çepel N., 1995. Orman ekolojisi. İstanbul Üniversitesi Orman Fakültesi, Yayın No: 433, 536 p., İstanbul.
Genç M., 1992. Ağaçlandırma potansiyelimiz, AGM'yi bekleyen sorunlar, fidanlık ve ağaçlandırma çalışmalarına ilişkin bazı öneriler. Orman Mühendisliği Dergisi, 10, 29-31.
Göktürk A., Ölmez Z., Temel F., Öncül Ö., 2004. Potential erosion areas in Artvin region with a general overview of afforestation and erosion control efforts. Kafkas Üniversitesi Artvin Orman Fakültesi Dergisi, 5 (in press).
Gümüs C., 2000. Ormancılık politikası. KTU Orman Fakültesi, Ders Notları, Yayın No: 62, Trabzon.
Hensley D.L., Carpenter P.L., 1986. Survival and coverage by several N2-fixing trees and shrubs on lime-avended acid mine spoil. Tree Planters' Notes, 29, 27-31.
Huntley J.C., 1990. Robinia pseudoacacia L. black locust. In: Burns, Russell M.; Honkala, Barbara H., technical coordinators. Silvics of North America. Volume 2. Hardwoods. Agric. Handb. 654. Washington, DC: U.S. Department of Agriculture, Forest Service: 755-761.
Kılıç A., Kurtuluş B., 1994. Meteorolojik bilgi bankası oluşturulması Rapor A: Değerlendirmeye alınan istasyonların bilgileri. DMİ Genel Müdürlüğü, Ankara.
Keresztesi B., 1980. The black locust. Unasylva, 32, 23-33.
Keresztesi B., 1988. The black locust. Akademia Kiado, Budapest.
Montagnini F., Haines B., Swank W.T., 1991. Soil-solution chemistry in black locust, pine/mixed-hardwoods and oak/hickory forest stands in the southern Appalachians, U.S.A. Forest Ecology and Management, 40, 199-208.
Toplu F., 2000. Yalancı akasya (Robinia pseudoacacia L.). Güneydoğu Anadolu Ormancılık Araştırma Müdürlüğü, Elazığ, Türkiye.
Ürgenc S., Boydak M., 1985. Türkiye'de ormaniçi ve ormandışı ağaçlandırma çalışmalarının bugünkü durumu ve hedefleri. İ.U. Orman Fakültesi Dergisi, 35 (2), 13-17.
Yahyaoğlu Z., Ölmez Z., 2003. Tohum teknolojisi ve fidanlık tekniği. Ders Notu, KAÜ Artvin Orman Fakültesi, Yayın No:2, Artvin.
Table 1. Showing some parameters for the sample plots
Sample Plots / Location of Slope / Mean of Seedling Height(cm) / Mean of Root Collar Diameter (mm) / Exposure
1 / Upper slope / 83.3 / 12.9 / South-west
Middle slope / 111.7 / 15.9
Lower slope / 111.9 / 17.3
2 / Upper slope / 65.7 / 11.2 / South-east
Middle slope / 92.1 / 15.0
Lower slope / 78.9 / 13.8
3 / Upper slope / 110.0 / 15.2 / East
Middle slope / 122.7 / 16.4
Lower slope / 179.2 / 22.4
Table 2. Some soil properties of the sample plots
Sample Plots / Location of slope / Profile number / pH / Soil texture1 / Upper / 1 / 7.60 / SCL
1 / Upper / 2 / 7.84 / SCL
1 / Upper / 3 / 7.54 / SCL
1 / Middle / 1 / 7.47 / SCL
1 / Middle / 2 / 7.46 / SC
1 / Middle / 3 / 7.58 / SCL
1 / Lower / 1 / 7.74 / SCL
1 / Lower / 2 / 7.70 / SCL
1 / Lower / 3 / 7.58 / SCL
2 / Upper / 1 / 6.67 / SCL
2 / Upper / 2 / 7.51 / SCL
2 / Upper / 3 / 7.59 / SC
2 / Middle / 1 / 7.60 / SCL
2 / Middle / 2 / 7.58 / SC
2 / Middle / 3 / 7.45 / SC
2 / Lower / 1 / 7.58 / SCL
2 / Lower / 2 / 7.56 / SCL
2 / Lower / 3 / 7.59 / SC
3 / Upper / 1 / 7.61 / SC
3 / Upper / 2 / 7.70 / SCL
3 / Upper / 3 / 7.59 / SCL
3 / Middle / 1 / 7.27 / SCL
3 / Middle / 2 / 7.35 / SCL
3 / Middle / 3 / 7.28 / SCL
3 / Lower / 1 / 7.67 / SCL
3 / Lower / 2 / 7.55 / SCL
3 / Lower / 3 / 7.57 / SCL
SCL: Sandy Clay Loam; SC: Sandy Clay
Table 3. Analysis of variance showing the relationship of the height of seedlings with different parameters (Means in column with the same letter are not significantly different from each other p<0.05).
Properties / Exposure / Number of sample (N) / Average of the seedlings height (cm) / ANOVA (F ratio) / Newman Keuls test resultsHeight - exposure / SE / 90 / 78.9 / a
SW / 90 / 102.3 / 61.56** / b
E / 90 / 137.5 / c
Properties / Location of slope / Number of sample (N) / Average of the seedlings height (cm) / ANOVA (F ratio) / Newman Keuls test results
Height –
Location of slope / Upper / 90 / 86.6 / a
Middle / 90 / 108.8 / 18.96** / b
Lower / 90 / 123.3 / c
Properties / Exposure / Number of sample (N) / Average of the root coller diameter (mm) / ANOVA (F ratio) / Newman Keuls test results
Root coller diameter - Exposure / SE / 90 / 13.3 / a
SW / 90 / 15.4 / 22.65** / b
E / 90 / 17.9 / c
Properties / Location of slope / Number of sample (N) / Average of the root coller diameter (mm) / ANOVA (F ratio) / Newman Keuls test results
Root coller diameter – Location of slope / Upper
Middle
Lower / 90
90
90 / 13.1
15.8
17.8 / 24.11** / a
b
c
NS : Not significant ** : significant at 95% significance level